An Interview with Tom Bruch
By Dick Koenig
Published in Volume 25, Number 4, Nov/Dec 2001
Photos by Carter Kudrle and Mark Bouljon
Tom Bruch’s Carrera on its first record run at the salt flats at Bonneville, August 22, 1966.
The racing and record-setting prowess of Carreras was established long ago. Most familiar are the long succession of victories at road courses, large and small, all over the world. The handling characteristics of these special 356s and their potent engines were the envy of all other racers who followed in their dust. Little known, however, is that the Carrera body received considerable distinction in its own right. The aerodynamic shape was exceptionally smooth and ideally suited for high speed competition of all types. Follow this story of the record-setting adventures of Tom Bruch at the Bonneville Salt Flats.
Dick Koenig. As I was driving over to Iowa City from Chicago all I saw was beautiful rolling hills and plush green farmland. You are in the midst of a picturesque, but very rural area. I can’t imagine it was any different 40 years ago. How did you get interested in Porsches, and Carreras, and Bonneville?
Tom Bruch. It’s no secret that we’re Iowa farm boys and we’re proud of it. You’re exactly right, though. The isolation in the 1960s was a large part of the appeal and the challenge for me when I got started.
DK. Could you go back to the beginning and talk about what happened?
TB. I was in the service at the tail end of the Korean conflict. I ended up being a medic and was stationed in San Francisco. That’s where I found out there were such things as Porsches. There was a dealer on Van Ness Avenue who actually had a 4-cam Carrera in his showroom, but on my medic pay, all I could do is look through the window. By then, I was already hooked on the little German cars. I was driving a supercharged VW at the time. It wouldn’t be long, however, before I was heavy into Porsches. But I’m getting a little ahead of the story.
After I got out of the service, I came home to Iowa and worked for a few years as a surgical technician at the hospital in Cedar Rapids. In the meantime, I had picked up an old pushrod Speedster and was playing with it. Pretty soon I was working on a few of the doctors’ cars at the hospital - their Porsches. One day, sometime in 1959 or ‘60, Porsche called me and asked if I wanted to work on their cars for real. I liked the idea and went to work for the VW-Porsche dealer, Empire Motors in Cedar Rapids. In the early days, they were the only dealer between Chicago and Denver. They were one of the first dealers in the Midwest, starting in the early ‘50s. I worked at this dealership for nearly 25 years and attended nearly all the training courses. Sometime in the mid-1980s, I opened my own shop, Bruch Motorwerks, in Iowa City and serviced VWs and Porsches until I retired last year. Now, I devote most of my time to racing.
DK. I have spoken with several of the service people from the early days here in the U.S., and all of them were in the bigger cities. That’s where most of the Porsches were, and still are. What was it like then?
TB. At the time, there weren’t more than 25 Porsches of all model 356s in the whole state. I probably serviced all of them plus most of the VWs. In addition, since we were located on the main interstate road traveling east-west, we got most of the breakdowns that were passing through. If I can digress for a moment, you might find this story amusing. In the ‘60s, neither Porsches nor Volkswagens were reliable, especially on long, hot cross-country trips. A lot of VW busses broke down. You can imagine a bus full of hippies traveling across the country in a bus overloaded with all of their possessions. They’d attach a broomstick to the tray under the dash and press the accelerator to the floor. Then, they’d wave the Peace Flag out the window and keep going until the motor broke. We had rows of busses that needed motors, but nobody with any money. They’d travel for hours in the 80-degree heat until the motor cooked. Many of the motors looked like they never had an oil change.
A large part of the challenge and intrigue for me back then was that the Porsches were so new and different. They were really rare cars out here. There was hardly anyone I could talk to, not like now where you have easy access through lots of communication channels. That was a large part of the fun of it–like being on the frontier and doing something new and different. One of my main sources of inspiration back then was the hot rod magazines as well as Road and Track. I really got excited about the stories of racing at Bonneville. It seemed like a real adventure. Names like Al Cadrobbi and Racer Brown were real big in the early 1960s. Cadrobbi, as you probably know, set some records in a Carrera Coupe. In 1965, I went to Bonneville for the first time to see what it was all about. I took my 36-horsepower VW modified with an Okrasa kit. That means I drove the car out there, raced it, and then drove back home. Almost nobody used trailers in those days. I went 90 mph and set a record. Even in those early days, competition was intense with the VWs. Many guys from California were into the Bugs already.
During this first experience I was bitten by the “Bonneville bug.” It has lasted for a lifetime and brought me immense enjoyment. I could learn more in a week at Bonneville than in five years at home. It was a tuner’s paradise. You could try all sorts of things in a short time and really test them. Also, ingenuity and inventiveness often counted more than money. You had to build many of the parts yourself and work out the combinations. There’s a lot of hard work involved. Money alone won’t do it. As you can see, this is a place where us Iowa farm boys were on an equal field with the big guns from Detroit.
Bonneville is the Great Mechanical Challenge. You are trying to get the most out of whatever cc’s you are playing with, but its not just the engine and horsepower. It took me a while to discover this, but there’s more. You have to look at the whole system, which includes aerodynamics, gearing and even the weather.
DK. What you’ve said, especially about aerodynamics, many of us take for granted today, but I imagine this was cutting edge thinking in the 1960s. I never heard of anybody talking about spoilers at that time. So, to continue your story, what happened after the “bug” got you? Is that when you turned to Porsches?
TB. Yes. In the meantime, I had picked up a 1956 Porsche Carrera GS Speedster (VIN 82058). I found it in a garage in Cedar Rapids. It came with two four-cam engines and all kinds of special tools. Somebody had started taking the engines apart and they were left in this condition for years. The car was stored under ladders, leaves, and who knows what. I ended up buying everything and got a real good deal. There wasn’t anybody in Iowa who knew anything about these engines, including me. However, I was excited to have a really nice Porsche. So, I took the Carrera stuff off and put in a pushrod Super engine. Actually, this turned out to be a very fine car. It didn’t have very high mileage and was in good condition. I used it for my daily driver for a while. When I decided to get serious about Bonneville, this Porsche was my choice.
DK. Do you know anything about the history of this car? It seems unusual to me that a Carrera would have two engines and repair tools. Was this somebody’s race car before you happened upon it?
TB. Originally, the car was owned by Loyal Katzke, an imported car dealer in Omaha, Nebraska. He raced the car in an SCCA race in Denver and finished second in class. Later in 1956 the car was sold to John Peters, also of Omaha. He entered the car in the race at Elkhart Lake (first run on the new track) and finished fourth overall. While this record was impressive, the engine wasn’t cared for properly and failed due to poor lubrication. A new engine was purchased and installed and the car sold to another fellow who reportedly used it as a daily driver until he blew the second engine. The car sat in a garage as I described until I bought it in 1962. I made up for lost time, you might say, racing in all kinds of solo events–hill climbs, auto crosses, etc. I really had fun with this car!
One of the things that seemed obvious to me from my first trip to Bonneville was the importance of selecting the right class–one where you can be competitive. For me, it meant that I couldn’t run the Carrera engine because I knew nothing about it and couldn’t afford the parts. I never thought that I could catch up with Al Cadrobbi’s records either. Budget was, and still is, a big concern. It’s not a good idea to pick a class where you have to compete with the big boys from the major car companies. Also, those classes where the record has been worked on by lots of people and the record is real high are probably too tough. So, I looked for classes where there wasn’t as much activity and I would have a chance for success.
The impound area
DK. This explains what you meant about ingenuity and creativity being the big challenges. The classes you chose were affordable and didn’t necessitate a large budget. Your challenges were more personal and mental. This rules out the Carrera engines because they were, and are, so expensive. What did you decide to do?
TB. I used the Carrera Speedster body because I had it and liked it. Porsches are very special to me. I choose the 1250 cc production class, even though it was a little unusual. I felt I would be competitive and I had many parts I could play with. I mixed and matched pieces to develop a 1192 cc motor. I used an early Type 506 Porsche case with a bore and stroke of 64 x 77. The car was run for two years. In the first of our low-buck efforts we set a record at about 104 mph. In 1967, the next year, we bettered the record to about 110 mph. That record held for probably fifteen years. My main competition during this time was from Fiat Abarths and Bugeye Sprites. In 1968, we went back again with the Carrera and three engines–the original 1250 and another little one, plus a 1600 Super 90. Unfortunately, it rained all week and we never had a chance to run any of them. I was so discouraged that I stopped racing for awhile and never competed with the GS Speedster again.
Waiting for the return run on Tuesday. Also on hand was the famous “Inch Pincher” VW.
DK. What did you do to develop the car into a record-holder?
TB. I worked mostly with the engine. In those days, more power, more power was what most people thought about. I did experiments with several things, especially with the 1250 cc class motors. Cylinders from 36 hp Volkswagens were used and we tried several pistons. On one occasion, we welded buttons on the piston tops to raise compression while in another we ground the tops flatter to have better spark. For heads, there was a set of early Porsche heads with 11:1 compression and a set of Okrasas that were at 10.3:1. The non-Factory style worked better. A variety of cams were tried. We started with the Isky 2J, which was a popular race grind of the day, and then went to a Crower. I even tried to grind my own lobes on a bench grinder. My thinking was so radical, let alone the profile I had developed, that I was written up in an article in Hot Rod magazine. Talk about wild experimentation! All of this occurred for our first run in 1966. While we were at Bonneville, I met Ed Iskenderian and told him about what I had done. After I returned home, he sent me a complementary R5T cam, which was his new, experimental profile. It was a very radical grind. I guess he admired my spirit and ingenuity.
A big part of my effort in those days was with the carbs and airflow. Basically, I see engines as air pumps. The more air that can flow through, the more power and torque that can be developed. That’s my basic idea in a nutshell. For the first year, I used Porsche 32 PBIC carbs and took the venturii out. I developed some ram tubes from aluminum drinking glasses. In 1967, I changed to a 4-carb manifold and used carbs from 36 hp VWs. This change wasn’t an improvement. The exhaust was the same for both years and consisted of separate headers for each cylinder joined to equal and adjustable in length.
During this time, most of my experimentation was on the intake side–carbs and manifolds. This may sound crazy today, but I assumed that the big challenge was getting more air in. I thought there wouldn’t be any problem for the exhaust gases to exit. Today, of course, everybody examines the complete system–both intake and exhaust. To study the intake flow, I developed my own air flow bench. This was unusual for the time, especially in Iowa. I took a used 35-gallon oil drum and attached a commercial vacuum cleaner to its side. Bolted to the top were a cylinder, head, manifold and carburetor simulating real-life intake air flow. I hung an incline manometer on the wall in my basement to measure resistance. With this device, I could make relative measurements, but the initial set-up was a little crude, I must admit. For instance, when the neighbor’s furnace went on, I could read it on my manometer. After a few years I figured out how to calibrate the bench by taking some comparative readings from a commercial device. Then, a little later, but after I was finished with the Carrera, I learned how to reverse the flow so that I could study exhaust as well. For the early days, and the small 1250 cc engines though, my apparatus worked just fine.
The Bonneville Crew: Dr. John Dickinson, Tom Bruch, Carter Kudrle, Howard “Bud” Jackson
DK. You worked mostly on the engine, as was the norm for the time. But you also said that there were many opportunities for learning. What new ideas did your Carrera experiences give you?
TB. One of the main ideas about Bonneville, and probably all forms of racing, is the importance of details. You have to carefully and methodically look at everything, as best you understand it at the time. While I started out to build a strong engine, I soon came to appreciate more fully the whole car as a complete package or system. Horsepower is only as good as you can get it down the racetrack. Two of the other things I learned more about from the Carrera are aerodynamics and gearing. I said before that I bought the Speedster because I liked it. After Bonneville, I really began to appreciate its shape. The body was far more slippery than many others–an MG, for instance, or my VW. Porsche’s design was way ahead of its time. I probably could have gone faster if the Porsche had been a coupe. Aerodynamically, the coupe body has better airflow. But, I used what I had, which was a Speedster with a hardtop. Replacing the soft top cleaned up the airflow a lot.
One if the things we did was study the airflow to find out where it was turbulent. We taped little pieces of yarn all over the car and then observed what they did when the car was traveling at speed. A friend drove the car down the road and I followed behind to take pictures of the yarn. You want the air to slip over the body, and the yarn, as smoothly as possible. In those areas where the yarn fluttered we knew there was turbulence and an interruption of the airflow. You get a disruption in the air if there’s a wide gap in the hood or if a door is misaligned. Sometimes this felt like splitting hairs, but that’s what Bonneville is all about-splitting hairs. A side-view mirror is worth a half-mile an hour. There are minor things you can do to adjust the panels because, for the most part, the air moved smoothly. The body shape was excellent for the time and is very good by today’s standards as well. There was, however, some turbulence in the back end.
The change that made the most difference was an adjustment to the deck lid. We extended the latch about one inch so that the lid was slightly opened, yet secure. This change was like a little spoiler and gave us an extra 3 mph. In those days, there wasn’t any information about spoilers, so there weren’t any rules either. That meant we could do anything we wanted. As long as you had a deck lid, you could do anything. We found that having the lid open and sticking up a little was the best combination. We tried a small two-inch lip spoiler sticking up from the rear edge of the deck lid and it slowed the car down about 6 mph.
There are other changes we might have made but didn’t think of at the time. You might be amazed, but this was all so new to us. The front end is an obvious one. A little rake and nose down attitude would have been a big help. This is a 30-minute adjustment and no trouble at all. Another thing I remember is the effect of the wind on the Glaspar hardtop. At around 100 mph, the side windows started bowing out at the top. They moved out maybe four inches. It made me nervous because I could look out without even seeing a window. When I slowed down, the windows sucked back in again. This told me that there was a lot of trapped air that entered the cockpit from outside. I never solved this problem even though I was aware of it. Better seals probably would have helped, or maybe we could have made stiffeners to hold the windows a little better. Looking back now, there could have been another 6-7 mph if we could have solved this problem.
Gearing is another area that seems so apparent today. I think we were only turning 5,300 rpm in fourth gear, but the engine was capable of 6,000 rpm. The motor didn’t have any torque at the top end. I might have helped myself with something as simple as running smaller diameter tires on the rear. Changing the gears would have been an option too.
Installing a “wild” mill in the makeshift paddock after Thursday’s record run. Below: a sample of the detailed records Tom kept.
DK. I know you’re still racing today. How did your early Carrera experiences help you with your present efforts?
TB. With the technology we have now and with the same car and engine, we could probably run 120 mph easily. Everyone is a lot smarter than 40 years ago. Today, guys are turning 140 mph with a little 1-litre Geo motor. So, 120 with our old motor is not beyond the realm of reason. But, the most important lesson I carried away from the Carrera is the importance of details. Bonneville is about getting all the details right. Also, time keeps moving so you have to always look for new ideas. A big mistake many people make is to look for inspiration only in their own area of racing. Their focus is too narrow. I get fresh ideas from all types of racing. Let me give you a few examples.
I learned a lot from the Formula V boys. They work hard for even a half-horsepower. One of the things they do when building an engine is turn it over with a torque wrench to measure drag and friction. Their goal with a fully assembled engine is to have almost no reading on the torque wrench. Today I pay much more attention to tolerances. Its important that seals aren’t dragging and that bearings are as small as possible. Also, there are many types of rings available that don’t drag as much as the old timers. If you can cut friction to a minimum, you can gain about three horsepower. This technique can be carried too far, of course, and the engine will become dangerously sloppy. In general, I set tolerances much looser than I used to. Since I need to make only a few runs I don’t need to build as tight an engine as if I were doing endurance racing.
Another area where I have learned concerns oil level and how it restricts the rotation of the crankshaft. Based upon what they do in NASCAR, I now build “scrapers” to help remove oil from the crankshaft. When the crank is rotating, oil clings to it and acts like a viscous rope that retards rotation. The scraper is located a few thousandths away from the crank and rods, and disperses the oil, reducing the buildup on these rotating parts. If the scraper is designed right, it frees up the crankshaft and might add ten horsepower while returning the oil to the bottom of the crankcase where it can recirculate and help with cooling and lubrication. Perhaps you’re familiar with a 911 when too much oil was put in the crankcase; there just isn’t any power. In addition, today we have added many oil drains to our motors and make a deeper pan. The idea is that getting the oil away from the rotating mass makes the horsepower go up. On my dyno, I have been able to change the horsepower on a Chevy V8 by as much as 25 horsepower just by lowering the oil level with a deeper pan.
DK. These are some exciting insights that, as you say, you’ve been playing with. I get a real sense of your excitement for the mechanical challenges. In addition, I have noticed you at car shows and swap meets looking carefully at things and peeking under cars. You’re always looking for something new or different, aren’t you?
TB. I am constantly on the lookout. You never know where you will find something. All I need is a little clue or just a peek at something and then I can run with it. That’s the fun of it.
DK. What have you done recently with Porsches? I know that the Carrera Speedster is long gone and now owned by Mark Bouljon in Minnesota. (Ed. note: As of 2011, restored and residing in Italy.) Do you have any Porsche projects in the works?
TB. I have been working on several cars in the last few years. They are small engines because that’s what I like best. One of the more interesting is a 1 litre 911. You probably never heard of that engine before. What I did was to take a 2-liter engine and block off 3 of the cylinders. I developed counterweights to compensate for the pistons and made a 1000 cc engine. When we ran the engine the first time, it was in a 914-6 body that belonged to my neighbor, Lee Schlabaugh of Stalltek. We have a record of 109 mph in the standing mile and I feel pretty good about this. However, the car is way too heavy and acceleration was too slow.
A 914 with a three-cylinder 911 engine, another project that brought Tom a world land speed record.
DK. This sounds like an amazing record with an incredible engine, but I sense you’re not satisfied. What do you have in mind next?
TB. You’re correct, I’m not satisfied. You can’t stand still. There are a couple of things to do yet. On the engine, there’s still a balance problem I can’t solve. I have designed three different types of counterweights to offset the pistons that aren’t there, but there’s still a secondary vibration. You can’t see the vibration and you can’t feel it, but parts disappear from the engine. The vibration shakes things off which should never come off, like the bolts on top of the Webers and the insides of the distributors. What I think I need to do is put a harmonic balancer on the nose of the crankshaft. The engine will run 8,000 rpm and does make good power if I can solve this problem.
The other change I want to make is to use a lighter body. The 356 appeals to me because it is so good aerodynamically. The frontal area is comparatively small as is the drag coefficient. I think we could go much faster, but there might be an upper limit for the 356. I don’t want to sound too confident, but the 356 gets unstable around 140 mph. It’s real tricky to drive at this speed because the car wants to switch ends on you and spin around. The side profile, or shape of the 356 is like an inverted airplane wing–flat on the bottom and rounded on top. As air passes over the car it travels faster on top because it has more distance to travel over the rounded upper profile. Moving quicker, the topside air creates less downward pressure. So, the air underneath pushes the back of the car up because the pressures are unbalanced. All you need is a little wing in the back, like we simulated with the deck lid on the Speedster, and the problem would be corrected. Unfortunately, such modifications are no longer legal in production classes. I have to think a little more about this one.
DK. These are some really interesting stories, Tom. I’m happy you had the time to share them with us. I wish you the best of luck. I’ll be looking for your new records.
TB. I really would like to get the record in the 1-liter class with that 911, but it wouldn’t be any cakewalk. The record is already up to 121 mph. Also, I have to prepare a 356 body, which hasn’t been done yet. Say, how about if we use one of your Carreras? That would be an excellent way to continue the Carrera story.
DK. You never know, anything is possible, but I just can’t imagine what all the salt at Bonneville would do. Let’s just wait and see. The idea certainly is intriguing. Thanks again, Tom.
By Dick Koenig
Published in Volume 25, Number 4, Nov/Dec 2001
Photos by Carter Kudrle and Mark Bouljon
Tom Bruch’s Carrera on its first record run at the salt flats at Bonneville, August 22, 1966.
The racing and record-setting prowess of Carreras was established long ago. Most familiar are the long succession of victories at road courses, large and small, all over the world. The handling characteristics of these special 356s and their potent engines were the envy of all other racers who followed in their dust. Little known, however, is that the Carrera body received considerable distinction in its own right. The aerodynamic shape was exceptionally smooth and ideally suited for high speed competition of all types. Follow this story of the record-setting adventures of Tom Bruch at the Bonneville Salt Flats.
Dick Koenig. As I was driving over to Iowa City from Chicago all I saw was beautiful rolling hills and plush green farmland. You are in the midst of a picturesque, but very rural area. I can’t imagine it was any different 40 years ago. How did you get interested in Porsches, and Carreras, and Bonneville?
Tom Bruch. It’s no secret that we’re Iowa farm boys and we’re proud of it. You’re exactly right, though. The isolation in the 1960s was a large part of the appeal and the challenge for me when I got started.
DK. Could you go back to the beginning and talk about what happened?
TB. I was in the service at the tail end of the Korean conflict. I ended up being a medic and was stationed in San Francisco. That’s where I found out there were such things as Porsches. There was a dealer on Van Ness Avenue who actually had a 4-cam Carrera in his showroom, but on my medic pay, all I could do is look through the window. By then, I was already hooked on the little German cars. I was driving a supercharged VW at the time. It wouldn’t be long, however, before I was heavy into Porsches. But I’m getting a little ahead of the story.
After I got out of the service, I came home to Iowa and worked for a few years as a surgical technician at the hospital in Cedar Rapids. In the meantime, I had picked up an old pushrod Speedster and was playing with it. Pretty soon I was working on a few of the doctors’ cars at the hospital - their Porsches. One day, sometime in 1959 or ‘60, Porsche called me and asked if I wanted to work on their cars for real. I liked the idea and went to work for the VW-Porsche dealer, Empire Motors in Cedar Rapids. In the early days, they were the only dealer between Chicago and Denver. They were one of the first dealers in the Midwest, starting in the early ‘50s. I worked at this dealership for nearly 25 years and attended nearly all the training courses. Sometime in the mid-1980s, I opened my own shop, Bruch Motorwerks, in Iowa City and serviced VWs and Porsches until I retired last year. Now, I devote most of my time to racing.
DK. I have spoken with several of the service people from the early days here in the U.S., and all of them were in the bigger cities. That’s where most of the Porsches were, and still are. What was it like then?
TB. At the time, there weren’t more than 25 Porsches of all model 356s in the whole state. I probably serviced all of them plus most of the VWs. In addition, since we were located on the main interstate road traveling east-west, we got most of the breakdowns that were passing through. If I can digress for a moment, you might find this story amusing. In the ‘60s, neither Porsches nor Volkswagens were reliable, especially on long, hot cross-country trips. A lot of VW busses broke down. You can imagine a bus full of hippies traveling across the country in a bus overloaded with all of their possessions. They’d attach a broomstick to the tray under the dash and press the accelerator to the floor. Then, they’d wave the Peace Flag out the window and keep going until the motor broke. We had rows of busses that needed motors, but nobody with any money. They’d travel for hours in the 80-degree heat until the motor cooked. Many of the motors looked like they never had an oil change.
A large part of the challenge and intrigue for me back then was that the Porsches were so new and different. They were really rare cars out here. There was hardly anyone I could talk to, not like now where you have easy access through lots of communication channels. That was a large part of the fun of it–like being on the frontier and doing something new and different. One of my main sources of inspiration back then was the hot rod magazines as well as Road and Track. I really got excited about the stories of racing at Bonneville. It seemed like a real adventure. Names like Al Cadrobbi and Racer Brown were real big in the early 1960s. Cadrobbi, as you probably know, set some records in a Carrera Coupe. In 1965, I went to Bonneville for the first time to see what it was all about. I took my 36-horsepower VW modified with an Okrasa kit. That means I drove the car out there, raced it, and then drove back home. Almost nobody used trailers in those days. I went 90 mph and set a record. Even in those early days, competition was intense with the VWs. Many guys from California were into the Bugs already.
During this first experience I was bitten by the “Bonneville bug.” It has lasted for a lifetime and brought me immense enjoyment. I could learn more in a week at Bonneville than in five years at home. It was a tuner’s paradise. You could try all sorts of things in a short time and really test them. Also, ingenuity and inventiveness often counted more than money. You had to build many of the parts yourself and work out the combinations. There’s a lot of hard work involved. Money alone won’t do it. As you can see, this is a place where us Iowa farm boys were on an equal field with the big guns from Detroit.
Bonneville is the Great Mechanical Challenge. You are trying to get the most out of whatever cc’s you are playing with, but its not just the engine and horsepower. It took me a while to discover this, but there’s more. You have to look at the whole system, which includes aerodynamics, gearing and even the weather.
DK. What you’ve said, especially about aerodynamics, many of us take for granted today, but I imagine this was cutting edge thinking in the 1960s. I never heard of anybody talking about spoilers at that time. So, to continue your story, what happened after the “bug” got you? Is that when you turned to Porsches?
TB. Yes. In the meantime, I had picked up a 1956 Porsche Carrera GS Speedster (VIN 82058). I found it in a garage in Cedar Rapids. It came with two four-cam engines and all kinds of special tools. Somebody had started taking the engines apart and they were left in this condition for years. The car was stored under ladders, leaves, and who knows what. I ended up buying everything and got a real good deal. There wasn’t anybody in Iowa who knew anything about these engines, including me. However, I was excited to have a really nice Porsche. So, I took the Carrera stuff off and put in a pushrod Super engine. Actually, this turned out to be a very fine car. It didn’t have very high mileage and was in good condition. I used it for my daily driver for a while. When I decided to get serious about Bonneville, this Porsche was my choice.
DK. Do you know anything about the history of this car? It seems unusual to me that a Carrera would have two engines and repair tools. Was this somebody’s race car before you happened upon it?
TB. Originally, the car was owned by Loyal Katzke, an imported car dealer in Omaha, Nebraska. He raced the car in an SCCA race in Denver and finished second in class. Later in 1956 the car was sold to John Peters, also of Omaha. He entered the car in the race at Elkhart Lake (first run on the new track) and finished fourth overall. While this record was impressive, the engine wasn’t cared for properly and failed due to poor lubrication. A new engine was purchased and installed and the car sold to another fellow who reportedly used it as a daily driver until he blew the second engine. The car sat in a garage as I described until I bought it in 1962. I made up for lost time, you might say, racing in all kinds of solo events–hill climbs, auto crosses, etc. I really had fun with this car!
One of the things that seemed obvious to me from my first trip to Bonneville was the importance of selecting the right class–one where you can be competitive. For me, it meant that I couldn’t run the Carrera engine because I knew nothing about it and couldn’t afford the parts. I never thought that I could catch up with Al Cadrobbi’s records either. Budget was, and still is, a big concern. It’s not a good idea to pick a class where you have to compete with the big boys from the major car companies. Also, those classes where the record has been worked on by lots of people and the record is real high are probably too tough. So, I looked for classes where there wasn’t as much activity and I would have a chance for success.
The impound area
DK. This explains what you meant about ingenuity and creativity being the big challenges. The classes you chose were affordable and didn’t necessitate a large budget. Your challenges were more personal and mental. This rules out the Carrera engines because they were, and are, so expensive. What did you decide to do?
TB. I used the Carrera Speedster body because I had it and liked it. Porsches are very special to me. I choose the 1250 cc production class, even though it was a little unusual. I felt I would be competitive and I had many parts I could play with. I mixed and matched pieces to develop a 1192 cc motor. I used an early Type 506 Porsche case with a bore and stroke of 64 x 77. The car was run for two years. In the first of our low-buck efforts we set a record at about 104 mph. In 1967, the next year, we bettered the record to about 110 mph. That record held for probably fifteen years. My main competition during this time was from Fiat Abarths and Bugeye Sprites. In 1968, we went back again with the Carrera and three engines–the original 1250 and another little one, plus a 1600 Super 90. Unfortunately, it rained all week and we never had a chance to run any of them. I was so discouraged that I stopped racing for awhile and never competed with the GS Speedster again.
Waiting for the return run on Tuesday. Also on hand was the famous “Inch Pincher” VW.
DK. What did you do to develop the car into a record-holder?
TB. I worked mostly with the engine. In those days, more power, more power was what most people thought about. I did experiments with several things, especially with the 1250 cc class motors. Cylinders from 36 hp Volkswagens were used and we tried several pistons. On one occasion, we welded buttons on the piston tops to raise compression while in another we ground the tops flatter to have better spark. For heads, there was a set of early Porsche heads with 11:1 compression and a set of Okrasas that were at 10.3:1. The non-Factory style worked better. A variety of cams were tried. We started with the Isky 2J, which was a popular race grind of the day, and then went to a Crower. I even tried to grind my own lobes on a bench grinder. My thinking was so radical, let alone the profile I had developed, that I was written up in an article in Hot Rod magazine. Talk about wild experimentation! All of this occurred for our first run in 1966. While we were at Bonneville, I met Ed Iskenderian and told him about what I had done. After I returned home, he sent me a complementary R5T cam, which was his new, experimental profile. It was a very radical grind. I guess he admired my spirit and ingenuity.
A big part of my effort in those days was with the carbs and airflow. Basically, I see engines as air pumps. The more air that can flow through, the more power and torque that can be developed. That’s my basic idea in a nutshell. For the first year, I used Porsche 32 PBIC carbs and took the venturii out. I developed some ram tubes from aluminum drinking glasses. In 1967, I changed to a 4-carb manifold and used carbs from 36 hp VWs. This change wasn’t an improvement. The exhaust was the same for both years and consisted of separate headers for each cylinder joined to equal and adjustable in length.
During this time, most of my experimentation was on the intake side–carbs and manifolds. This may sound crazy today, but I assumed that the big challenge was getting more air in. I thought there wouldn’t be any problem for the exhaust gases to exit. Today, of course, everybody examines the complete system–both intake and exhaust. To study the intake flow, I developed my own air flow bench. This was unusual for the time, especially in Iowa. I took a used 35-gallon oil drum and attached a commercial vacuum cleaner to its side. Bolted to the top were a cylinder, head, manifold and carburetor simulating real-life intake air flow. I hung an incline manometer on the wall in my basement to measure resistance. With this device, I could make relative measurements, but the initial set-up was a little crude, I must admit. For instance, when the neighbor’s furnace went on, I could read it on my manometer. After a few years I figured out how to calibrate the bench by taking some comparative readings from a commercial device. Then, a little later, but after I was finished with the Carrera, I learned how to reverse the flow so that I could study exhaust as well. For the early days, and the small 1250 cc engines though, my apparatus worked just fine.
The Bonneville Crew: Dr. John Dickinson, Tom Bruch, Carter Kudrle, Howard “Bud” Jackson
DK. You worked mostly on the engine, as was the norm for the time. But you also said that there were many opportunities for learning. What new ideas did your Carrera experiences give you?
TB. One of the main ideas about Bonneville, and probably all forms of racing, is the importance of details. You have to carefully and methodically look at everything, as best you understand it at the time. While I started out to build a strong engine, I soon came to appreciate more fully the whole car as a complete package or system. Horsepower is only as good as you can get it down the racetrack. Two of the other things I learned more about from the Carrera are aerodynamics and gearing. I said before that I bought the Speedster because I liked it. After Bonneville, I really began to appreciate its shape. The body was far more slippery than many others–an MG, for instance, or my VW. Porsche’s design was way ahead of its time. I probably could have gone faster if the Porsche had been a coupe. Aerodynamically, the coupe body has better airflow. But, I used what I had, which was a Speedster with a hardtop. Replacing the soft top cleaned up the airflow a lot.
One if the things we did was study the airflow to find out where it was turbulent. We taped little pieces of yarn all over the car and then observed what they did when the car was traveling at speed. A friend drove the car down the road and I followed behind to take pictures of the yarn. You want the air to slip over the body, and the yarn, as smoothly as possible. In those areas where the yarn fluttered we knew there was turbulence and an interruption of the airflow. You get a disruption in the air if there’s a wide gap in the hood or if a door is misaligned. Sometimes this felt like splitting hairs, but that’s what Bonneville is all about-splitting hairs. A side-view mirror is worth a half-mile an hour. There are minor things you can do to adjust the panels because, for the most part, the air moved smoothly. The body shape was excellent for the time and is very good by today’s standards as well. There was, however, some turbulence in the back end.
The change that made the most difference was an adjustment to the deck lid. We extended the latch about one inch so that the lid was slightly opened, yet secure. This change was like a little spoiler and gave us an extra 3 mph. In those days, there wasn’t any information about spoilers, so there weren’t any rules either. That meant we could do anything we wanted. As long as you had a deck lid, you could do anything. We found that having the lid open and sticking up a little was the best combination. We tried a small two-inch lip spoiler sticking up from the rear edge of the deck lid and it slowed the car down about 6 mph.
There are other changes we might have made but didn’t think of at the time. You might be amazed, but this was all so new to us. The front end is an obvious one. A little rake and nose down attitude would have been a big help. This is a 30-minute adjustment and no trouble at all. Another thing I remember is the effect of the wind on the Glaspar hardtop. At around 100 mph, the side windows started bowing out at the top. They moved out maybe four inches. It made me nervous because I could look out without even seeing a window. When I slowed down, the windows sucked back in again. This told me that there was a lot of trapped air that entered the cockpit from outside. I never solved this problem even though I was aware of it. Better seals probably would have helped, or maybe we could have made stiffeners to hold the windows a little better. Looking back now, there could have been another 6-7 mph if we could have solved this problem.
Gearing is another area that seems so apparent today. I think we were only turning 5,300 rpm in fourth gear, but the engine was capable of 6,000 rpm. The motor didn’t have any torque at the top end. I might have helped myself with something as simple as running smaller diameter tires on the rear. Changing the gears would have been an option too.
Installing a “wild” mill in the makeshift paddock after Thursday’s record run. Below: a sample of the detailed records Tom kept.
DK. I know you’re still racing today. How did your early Carrera experiences help you with your present efforts?
TB. With the technology we have now and with the same car and engine, we could probably run 120 mph easily. Everyone is a lot smarter than 40 years ago. Today, guys are turning 140 mph with a little 1-litre Geo motor. So, 120 with our old motor is not beyond the realm of reason. But, the most important lesson I carried away from the Carrera is the importance of details. Bonneville is about getting all the details right. Also, time keeps moving so you have to always look for new ideas. A big mistake many people make is to look for inspiration only in their own area of racing. Their focus is too narrow. I get fresh ideas from all types of racing. Let me give you a few examples.
I learned a lot from the Formula V boys. They work hard for even a half-horsepower. One of the things they do when building an engine is turn it over with a torque wrench to measure drag and friction. Their goal with a fully assembled engine is to have almost no reading on the torque wrench. Today I pay much more attention to tolerances. Its important that seals aren’t dragging and that bearings are as small as possible. Also, there are many types of rings available that don’t drag as much as the old timers. If you can cut friction to a minimum, you can gain about three horsepower. This technique can be carried too far, of course, and the engine will become dangerously sloppy. In general, I set tolerances much looser than I used to. Since I need to make only a few runs I don’t need to build as tight an engine as if I were doing endurance racing.
Another area where I have learned concerns oil level and how it restricts the rotation of the crankshaft. Based upon what they do in NASCAR, I now build “scrapers” to help remove oil from the crankshaft. When the crank is rotating, oil clings to it and acts like a viscous rope that retards rotation. The scraper is located a few thousandths away from the crank and rods, and disperses the oil, reducing the buildup on these rotating parts. If the scraper is designed right, it frees up the crankshaft and might add ten horsepower while returning the oil to the bottom of the crankcase where it can recirculate and help with cooling and lubrication. Perhaps you’re familiar with a 911 when too much oil was put in the crankcase; there just isn’t any power. In addition, today we have added many oil drains to our motors and make a deeper pan. The idea is that getting the oil away from the rotating mass makes the horsepower go up. On my dyno, I have been able to change the horsepower on a Chevy V8 by as much as 25 horsepower just by lowering the oil level with a deeper pan.
DK. These are some exciting insights that, as you say, you’ve been playing with. I get a real sense of your excitement for the mechanical challenges. In addition, I have noticed you at car shows and swap meets looking carefully at things and peeking under cars. You’re always looking for something new or different, aren’t you?
TB. I am constantly on the lookout. You never know where you will find something. All I need is a little clue or just a peek at something and then I can run with it. That’s the fun of it.
DK. What have you done recently with Porsches? I know that the Carrera Speedster is long gone and now owned by Mark Bouljon in Minnesota. (Ed. note: As of 2011, restored and residing in Italy.) Do you have any Porsche projects in the works?
TB. I have been working on several cars in the last few years. They are small engines because that’s what I like best. One of the more interesting is a 1 litre 911. You probably never heard of that engine before. What I did was to take a 2-liter engine and block off 3 of the cylinders. I developed counterweights to compensate for the pistons and made a 1000 cc engine. When we ran the engine the first time, it was in a 914-6 body that belonged to my neighbor, Lee Schlabaugh of Stalltek. We have a record of 109 mph in the standing mile and I feel pretty good about this. However, the car is way too heavy and acceleration was too slow.
A 914 with a three-cylinder 911 engine, another project that brought Tom a world land speed record.
DK. This sounds like an amazing record with an incredible engine, but I sense you’re not satisfied. What do you have in mind next?
TB. You’re correct, I’m not satisfied. You can’t stand still. There are a couple of things to do yet. On the engine, there’s still a balance problem I can’t solve. I have designed three different types of counterweights to offset the pistons that aren’t there, but there’s still a secondary vibration. You can’t see the vibration and you can’t feel it, but parts disappear from the engine. The vibration shakes things off which should never come off, like the bolts on top of the Webers and the insides of the distributors. What I think I need to do is put a harmonic balancer on the nose of the crankshaft. The engine will run 8,000 rpm and does make good power if I can solve this problem.
The other change I want to make is to use a lighter body. The 356 appeals to me because it is so good aerodynamically. The frontal area is comparatively small as is the drag coefficient. I think we could go much faster, but there might be an upper limit for the 356. I don’t want to sound too confident, but the 356 gets unstable around 140 mph. It’s real tricky to drive at this speed because the car wants to switch ends on you and spin around. The side profile, or shape of the 356 is like an inverted airplane wing–flat on the bottom and rounded on top. As air passes over the car it travels faster on top because it has more distance to travel over the rounded upper profile. Moving quicker, the topside air creates less downward pressure. So, the air underneath pushes the back of the car up because the pressures are unbalanced. All you need is a little wing in the back, like we simulated with the deck lid on the Speedster, and the problem would be corrected. Unfortunately, such modifications are no longer legal in production classes. I have to think a little more about this one.
DK. These are some really interesting stories, Tom. I’m happy you had the time to share them with us. I wish you the best of luck. I’ll be looking for your new records.
TB. I really would like to get the record in the 1-liter class with that 911, but it wouldn’t be any cakewalk. The record is already up to 121 mph. Also, I have to prepare a 356 body, which hasn’t been done yet. Say, how about if we use one of your Carreras? That would be an excellent way to continue the Carrera story.
DK. You never know, anything is possible, but I just can’t imagine what all the salt at Bonneville would do. Let’s just wait and see. The idea certainly is intriguing. Thanks again, Tom.
