924Board.org

[82-T/A]

Hey guys,

When I was much younger, I used to take my 85 Fiero GT in I think E stock class? (Solo / SCCA). I'd kind of like to get back into it. I'm not overly familiar with the different racing classes, but I would very much like to end up racing on a course. I know they have some SCCA events at Moroso Motorsports Park (actual track racing). In any case, I'd like to build up a 924 in such a way that I would be able to take it from Solo to a road course when I have enough experience / track time, and I'm certified.

That brings me to my first question. I picked a 924 because I currently own a 944 and like the body style, the handling, and the feel of the car. I also know that there are quite a few 924s on eBay that typically go for really decent prices. I've seen a few (over the past year) that have trashed interiors, but mechanically it's in decent shape. I figured I would be able to pick up a running car for about $1,000 fairly local, and strip the interior.

Here's my other question... what class would I fit in if I was to completely gut my interior? I know that Solo 1 / 2 is VERY specific about the modifications you make. I know that I clearly wouldn't fit into the Stock, or Street Prepared, or Street Modified, so... if I WAS to make these changes to the car (completely gutting the interior of everything I didn't need) would I still be ALLOWED to Auto-X?

My last question has more to do with the car:

When I used to Solo with my 84 Fiero GT, it had a 4-Speed manual transmission. All other V6 Fieros came with the 5-Speed Getrag manual transmission. For most people, the 5-Speed was a much better car... but the gearing was something like 3.52:1. The gearing on my 4-Speed was a sick 4.10:1 that was swapped out from an 84 Fiero (this was apparently allowed because it was a similar car and considered a downgrade / upgrade from the same car). Being that it was a 4-Speed with such (short? or tall?) gears, I really did quite well and spent nearly all my time in 2nd gear.

The other question realted to the car itself is... I'm more specifically picking a 924 because I am under the impression that:

1 - The Audi 2.0 motor is much cheaper / easier to work on than the 944 (no balance shafts, a bit smaller, more room, parts are cheaper)

2 - The Audi 2.0 is NOT an interference motor. Is this correct? I know that in my 944, if the belt goes I lose all or most of my valves and I'd have to pull the head. I hate having that kind of pressure on me. I'm of the impression that the 924 with the 2.0 does NOT have this issue?



Thanks guys, I really appreciate it. I'm looking forward to this!!! I don't know what I'm looking forward to more, building the car, or actually racing it!!!


Oh! Just had to edit this really quick. I had one more question. Can anyone tell me what would be the best YEAR for the car (with my needs / goals in mind). I'm speaking in terms of fuel injection and whatnot. Did they make a carbureted 924? I love carburetors and just don't have very many carbureted cars. Just my Trans Am and the Volkswagen Bus. I think it would be really cool to have a carbed 924. If not, what is the easiest fuel injection system they offered? I hate dealing with DMEs and reference sensors. It would be so nice if Porsche had put an OBD-1 system in.




Thanks!!!
_________________
Todd,
2006 Pontiac Solstice
2002 Ford Crown Victoria LX-P74
1987 Pontiac Fiero SE / V6
1984 Porsche 944
1981 Pontiac Trans Am WS6
1973 Volkswagen Type-2 Transporter

[924RACR]

Many questions requiring a long answer - not gonna get that right now, too much going on, but some quick answers.

Yes, the 2.0L 924 is the less-expensive, non-interference Audi motor. No carbs, and swapping them on will likely bump you into a rather expensive class. I don't autox, can't speak to the rules, actually hate it, but can't imagine that doing much good for you. Just get the CIS running properly, it's far more consistent. No sensors to dick with or screw you up.

Years - later the better. '80-onward, get the 5-speed yes, and the 5-lug brakes (same as your 944 - though they can be retrofit to earlier cars if needed).

924's are definitely faster and more capable than a Fear-O - beat plenty of the V6 variety with my 2.0L NA on track!

Looks like you're also talking about going full-on road racing - as we're doing currently. Can't go wrong running ITB in a 924 - very competitive. Just takes a while to get the car debugged - so all the better to have it as a street car first. Debugging a non-streetable car while you're racing it can suck. Prep level for ITB (Improved Touring) is pretty much equivalent to one of the Solo classes, I think it's Prepared?? Shocks/struts/springs/t-bars are free, minimal engine work (balance/blueprint and rebuild is basically it), stock trans with free diff, and DOT radial race tires (Hoosiers are the class of the field). Most of the 944 suspension bits bolt right on, so not hard to do; main PITA is the engine, there isn't much in the way of pro 924 motor builders. Then again, that could be a good thing - Milledge, the pro 944 motor builder, charges something like $12-15k for a 944 motor!!!
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[82-T/A]

Thanks Vaughn! (Despite the dig to my Fiero!!!).

I did some research on the CIS K-Jetronic between the time I posted this, and read your response. As I understand it, it's basically mechanical fuel injection, so there is NO computer involvement at all. I guess I'll just want to make sure I don't get a California version so I don't have to deal with the lambda stuff. Sounds like that's really what I want. I seem to remember my old Volvo 240 Turbo Wagon had something similar. It had some air valve, and a huge fuel "distributor" or something with a series of little metal tubes that branched out and ported to the base of the intake. I didn't know a whole lot about cars then, so I wasn't aware of what that was that I had. Looking back now, I know it had an ECM, so I guess it was an KE or something? To me it sounds like the best of both worlds really.


My reason for doing Auto-X is that I do not have any experience on a track. My understanding is that before you can do this, you must have a license, or be certified by a driving school before the SCCA will allow you to be on a track with other racers (for their own protection against the inexperienced). Auto-X as you say, will allow me to tune the car, but at the same time get more comfortable with it's handling.


I'd probably do all my own engine work, I just have a machine shop do the machining, and assemble it myself. Are there any "924 / 2.0" specific modifications that yield significant gains? I know with several of the other cars that I've had, there are a few things that typically yield significant gains. Like... for example, on the Fiero V6 exhaust logs... hogging out the flanges on the inside will yield 8hp on a stock motor, or like on the Porsche 944, swapping to the later year tubular exhaust manifold from the cast iron one will yield 9-10 ft-lbs of torque in the lower rpms... something like that. Is there anything with the 924 that's similar?


I'm going to have to read the rules...

Do you have any pictures of your 924?



Thanks!!!
_________________
Todd,
2006 Pontiac Solstice
2002 Ford Crown Victoria LX-P74
1987 Pontiac Fiero SE / V6
1984 Porsche 944
1981 Pontiac Trans Am WS6
1973 Volkswagen Type-2 Transporter

[924RACR]

Well, I do have a website... (hint hint)

Correct; the earlier non-E CIS is simpler to deal with... and yes, lots of Volvos, among others, run CIS - very common in Euro cars in the 70's-80's.

Actually, to get a race license, you don't really need anything other than a valid state driver's license and time and money. You can even rent a racecar for school! But the route you suggest is preferable; better to start learning about vehicle dynamics at lower speeds first!

There's actually another intermediate step for you, between autox and racing, that I'd recommend - Driver's Education events at the track. Street or race cars, on track turning laps at speed, with only very limited passing allowed (on straights) and with instruction. That'll get you up to speed well too. PCA does this, as does NASA, SCCA's getting started with it, and most car clubs do it to (Corvette, Neon, Alfa, BMW, etc). So there's lots of opportunities to get track time.

Note that tuning the suspension for autox is different than road course - decidedly different performance requirements.

Definitely read the rules - it's easy to do something that'll bump you to the next class up, where you're really uncompetitive...
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[John Brown]

We have Mikuni carbs on a 924 and I do NOT think they got us much. Except some great throttle response. In fact, I suspect we got no power at all. But did I mention terrific throttle response? And they sound and look cool.

It is not just Ca cars with lambda. Any 924 after 80 and later has the lambda system. It's not really a problem. If the computer dies you could replace it with a simple square wave signal to the 'frequency valve'. And, I've always thought controlling the frequency valve would be a good way to modify the mixture. Note that these early cars only actively change the mixture at idle. The remainder of the time the frequency valve is run at a constant duty cycle. Which is why you can remove the O2 sensor and they run better.

DO find a car with the big brakes. More in another thread.
_________________
John
80 931 - #931 44Cup
99 Escalade - tows track cars
gone but not forgotten: original 924.org car - 82

[endwrench]

Hope I'm not talking out of turn here as I don't race a 924 (just autocross) but it has been mentioned twice that you need the big brakes. There were VERY few 924's built with the 5 lug wheels and big 4 wheel disc brakes. If you can find one for a reasonable price then great, if not you will need to convert one. Most of the 931's (turbo version of the 924) had the big brakes. It may be easier and cheaper to find a 931 and convert it to a 924. Just a thought.

Also, there were 2 different tranny types. The Porsche "snail" and the Audi unit. The snail unit is tough as nails but have very weak syncros and almost no parts are available. I can almost garantee if you buy one of these 1st and 2nd syncro will be gone. The Audi unit is the same basic trans that is in your 944. The Audi unit was used 80-82 in NA and 81-82 in the turbos. All other 5 speed cars were the snail unit. 4 speed cars are based on the audi unit.

There is really NO hidden power to be had from a 924 NA motor. Small amounts can be had thru the usual blueprinting stuff and just stay away from the early 76-77.5 cylinder head.

Todd
_________________
'79 924NA. Rebuilt 9.5:1, MSDS header, Mega Squirt Injection, MJLJ-EDIS Ignition, 1.6L Whipple Charger and Intercooler, 10lbs Boost, 944 Trans, Custom HD Clutch.
"simsport" said....superchargers are better than turbos its official!....

[924RACR]

Converting a 931 would NOT be legal per SCCA - must have the correct VIN. It's still cheaper to get the brakes from a 944.
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype