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Marc Rozman: Joining Chrysler, EPA Tests, and Running Dynos

Marc Rozman is friendly and knows everyone; he has an encyclopedic knowledge of Chrysler cars and powertrains, and a reputation as being one of the company’s best dyno men. Marc is an officer of the Chrysler Employee Motorsports Association, a member of the High & Mighty II team, and an accomplished car photographer. Thanks to the Walter P. Chrysler Museum for providing space for this interview.

Marc in 1971

Starting Out at Chrysler: EPA Emissions Testing

The major points of Marc’s career, in chronological order:

  • March 1976: Driver/Mechanic in Highland Park 
  • Chassis rolls area: EPA audit testing
  • Advance chassis rolls testing, working with Gordon Finn on the Electronic Lean Burn systems for Chrysler and other automakers.
  • Road Test Garage: worked on lockup torque converter, vehicle repair, and pilot vehicle builds.
  • Engine Development Dynamometer Lab: first water brake durability test cells, then certification for 1978 440-3 truck engine. Last 440 tested.
  • Valve Train group: 318 roller cam, then 2.2L powder metal inset, then 2.2L roller cam
  • Moved to Cell 10 for final Turbo II development and calibration; then all Turbo IV VNT development and calibration
  • 3.3L V6: reduced coolant development, then turbo project
  • First 3.5L 4 valve V6 engine, development and calibration
  • First dynamometer operator to transfer to CTC PowerTrain Test Labs; set up High Dynamic Transient Test Cell in Wing A - Cell 11 (first cell to run)
  • 2.7L V6 development and calibration using High Dynamic Transient Test Cell
  • Advance testing of electronically control solenoid operated valve train (never got far, would have done much better ten years later)
  • Moved to Wing B Cell 1 - Did set up and sign off on one of the new performance test cells.
  • Set up Shaker test cell, set up Neon buck for testing motor mounts.
  • Moved back into performance test cell Wing B - Cell 9 doing 3.7L Jeep Liberty calibration.
  • Began work for Advance Engine Group (can't say what went on there, even now)

Q: When did you start at Chrysler?

I started Chrysler in March 1976. I had worked at a dealership for a year and a half, after Motech [Chrysler's Motech Automotive Education Center]. My father, working at Chrysler, said, “They’re hiring mechanics and technicians.” I wasn’t happy at the dealership, so I put my application in for Chrysler. My Dad didn’t really help at all; I put the application in the normal way, and I got a call pretty quick, and came in for an interview. They said, “Can you start tomorrow night?”

“Well, I guess I could, if I have to.” I went into work the next day and told them I was not coming back at all. I started working at Chrysler the next night on midnights, and it worked out pretty well. I was pretty happy with that.

I’ve always gone from one job to the next job without any break at all, from school to the Motech for a year, and then to the dealership and then to Chrysler, without any really lapse of time in between. So, I’ve always been on the job. I did 32 years at Chrysler.

We hired in as 268s, classification wise; that was considered an end of the line production classification. We were doing emissions testing for the production vehicles; we did six cars a night. The government required us to do an audit and pass so many vehicles per production.

I did that for five months… six months on midnights. It’s pretty exciting stuff. You drive the EPA cycle on the chassis rolls, they give you a TV screen, and it’s like a big video game. You have to pull a car in cold, after a 24 hour soak [sitting without running], you pull a vehicle in, strap it down on the chassis rolls, hook up a tail pipe, and sample. We have a big monitor on a set of casters, and we pull it by the car.

You start by doing a cold start on the vehicle, and there’s a trace on the screen, with two dots, and as you accelerate, the two dots move along with the trace. The trace comes up on the screen like a video game, you have to keep those two dots on the trace as you accelerate and brake according to the trace on the screen, that’s all part of the EPA cycle. It runs for 30-35 minutes, and then you have to stop the car, ten to twelve minutes soak [stop], restart the car, another ten minutes of driving, and that’s it. They sample exhaust gas and they judge our driving by keeping those dots on the trace of the screen.

You’re allowed so many errors, and as long as the driver did a good job, and as long as emissions were collected and came all correct, the car passed audit. If it failed, it went to a separate building where they would break it in more, run the engine more, and any big problems, correct per production specs, and then test it again. So, that was a fun process… simple but fun. [More test process information]

marc at the dyno

A big problem we had was with the big C-body Chryslers, with big plush velour interiors. You’d fire them up and halfway through the test, about 3:00 in the morning, running the test in the big Chrysler, you got the heat and the vibration and you’re kind of sitting there and you start to nod off a little bit. So, you had to keep yourself awake, and that was the hardest part, running those big C-bodies, and trying to do your job and keep awake and make those things pass, because if you passed you could move on. That’s a good thing, but the more problems you had, it wasn’t good for the company or for our production. So, all in all, it was a neat experience.

When things did fail, what was usually the problem?

If the car failed, they went to a different garage or a different building altogether. Most of the time you actually ran more time on the engine to break the engine in.

If it was some obvious big time problem, they would correct it, if it was a EGR valve or the timing was off or that kind of stuff, that would probably happen back then. But ’76 was still pretty early, and a lot of the emissions and components, they didn’t always work well. So, EGR valves would hang up, that kind of thing. So, if you could replace the part and get it back on, and run it.

marc rozman and michelin man

When I worked at the dealership, I did new car prep. I would get these cars in sometimes, brand new cars, the rear tires were half melted. How did this happen, how can they ship a car out with these tires looking that bad? Once I started doing the auto testing and I saw the mileage accumulation, let’s say, they ran the car for an hour on the chassis rolls, unattended, the tires would get hot and they start to break up. That’s what was causing what I saw, later on in the dealership. Those cars tended to be a lot grubbier too. They’re lived in more, wrappers and pop cans in the back seat. It was due to that process. But it was a learning curve there, but it was kind of fun.

But most of the cars were pretty good back then. The small cars were good, but our problem was testing full size vans, manual brakes, manual shift, three speed on the tree. It was not fun to test, because you’re trying to shift gears, trying to keep those two dots on the trace properly, while you’re shifting gears, with the manual brake, trying to stop the rolls from turning, that was a real chore and a lot of guys couldn’t do it. It’s just that it takes a certain knack to be able to shift gears and keep it happy too.


So, for a while there, they started requesting me to drive those cars, because I could get them to pass. I made it a game, and if you do a game enough, and you don’t mind doing it, if you have fun playing it, you could usually win. I did that pretty well, and then people got upset because they were requesting me to drive, and, like I’m better than them. But… then you drive and you pass it then.

So the other guys get the cushy cars and I got the beat up vans and trucks that had the stick shifts and hard seats, but it was fun though. I enjoyed it. When you’re young, it’s easier to do that kind of stuff. So, I didn’t mind doing it back then.

That still happens today?

That EPA cycle, I believe, is the same cycle. They went to LA some point in time in the early ’70s, took a vehicle and recorded the drive cycle, going from point A to point B in LA. It was some series of streets, with some highway, stop and go, stopping somewhere for coffee in the morning, probably, and then you got back in the car, and you did some more driving. But it was basically a cycle that was based off of a recorded drive someone did in LA, some point in time. That became the EPA cycle, and I’m not sure how they figure what emissions should be coming out of there.

And that’s why when we were doing our calibration work in the engine dyno, everything’s based on what that EPA cycle does, they know what rpm you’re in, what gear, gear unit time. So, you know that, in those windows of operation, we had to have the best possible emissions for those windows.

You know, we’re not doing WOT [wide open throttle], where you’re going full throttle at 90 miles an hour, so, we can make that what we want, because it’s not in the EPA cycle. So, the key thing is make your EPA cycle numbers for [the tested RPMs] your best possible emissions.

Outside that window, you can get richer, if you want to, and add more fuel, and still be passable. It’s an odd thing, where it’s a good thing there, but at the same time, you can get around it at times, too. So, like everything you do, there’s always a way to do things.

don garlits with marc rozman

The newer cars are a lot better now, of course, they’re easier to calibrate, and you can run it leaner longer, and keep the driver happy, too. Before you really didn’t know what we had to do, at times, and we ran it richer at times, to make it happy … but it’s a lot easier to do now. A lot more cars, I’m sure, pass better. But they have gotten tight around the tolerances too, though.

They have chassis rolls now. Not only for chassis EPA, but for doing development work. If you have a calibration you’re doing on a brand new car that’s coming out next year, you have to get that car set up. Not only do you have to have good numbers on the dyno, but you have to have good numbers on the car, and it’s all tested before it even goes to that final stage, where it goes through a production auto test.

They know what’s going in there, when it goes in there, and they’re pretty confident that it’s going to pass, normally. So, it’s keeping us busy, even today, that’s good.

How the dyno cells are run

It’s funny because people don’t realize that depending on what program you’re working on, like I did the 3.5, I did the 2.7, those are pretty much your thing. What you’re working on, that’s what you’re involved in. You may have the guy running a two liter next to you, you may hear conversations and what-have-you, but that’s not your project. You may be aware of some things, but you’re not directly involved in it to know all the details.

Building 139, 1980
I was the first operator in this building and help get it up and running. The 2.2L is the 1987 one built at Trenton plant. This building was done and worked well in a number of ways. It was the first large-scale use of computers; the older cells were using standalone IBM PCs. We could literally change engines in 15 minutes.

I did the V6 primarily. I did the four cylinder, originally, with the turbos and the Turbo II and Turbo IV, and then, in the cells that were back in the old days, you were pretty much by yourself. You were kind of standalone, and if you ventured out into the building, you could talk to your friends, but pretty much you went into work, and you sat in a test cell, and I always ate lunch there, too… now you do your testing, do your lunch and do your testing and you go home.

The newer cells in Auburn Hills are more open, you can socialize a lot more, which is good not only for work but for just staying awake. You have more of a chance to talk to other guys; even Auburn Hills said they tried to get a certain platform or group in a common area. There are cells in what we call quads, where there’s four cells in a quad. It’s a hallway with a left side, right side. So, you’re in a quad, and it may have other operators there, or you may be there by yourself.

But mostly they have multiple operators, and you may have a partner next to you. Normally, you ran the same group in the same areas. It just makes sense. The engineer has an engine down the hall, and one here and one over there, it does make sense for logistics for the engineer.

viper in test area

It depends on the test cell, but lots of times we were grouped together, but there were times when the engine next to you might have been a different project altogether, a different engineer, and you see and talk to them and hear their conversations, but I never had a whole lot of involvement in those.

We have a normal test we would run during the week, but if you put down for overtime, if your project was working overtime, they would always put you in your test cell. If your test cell was not working, and you worked overtime, it could be a different test cell, a different engine, which that wasn’t always the best, because you didn’t know that engine.

Some tests are pretty simple, some test are more complex, but as long as the engineer was there, too, you could run the test. But lots of times, you may get a feel for what’s going on, what are you doing, what are you looking for? I always try to find out ahead of time what we are watching for, what we are looking at, so I know what I have to watch out for.

The Marc Rozman interview by section

  1. Joining Chrysler, EPA testing, and running the dyno
  2. At the road test garage; working the water brake
  3. The famous Cell 13 and Hemi testing; working with legends
  4. Last 440, Pro Stock 355, and 3.5 V6
  5. Roller cams, cold oil, and snapping rocker arms
  6. Turbo 3.3, exploding engines, and troubleshooting
  7. The shaker table
  8. Working with engineers: learning and troubleshooting
  9. Marc’s 1969 Dodge Charger

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