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KDJones2000 · Joined: 14 Sep 2010 Posts: 322 Location: Phoenix, AZ

It's time to finally start to update everyone on the 924 that we are getting ready for what is likely going to be a Chumpcar endurance race sometime this year.

I have already been asking around regarding some of the brake issues we have encountered, and also installing our Autopower cage. Thanks already for the help, and I am sure that we will have more questions as we go along.

First some background. Our team consists of 3 944 guys, plus one non-Porsche person. We have had 944's for anywhere from a couple of years to about 15, so we know our way around these cars and have an idea of what to expect.

With the increased interest in LeMons and Chumpcar racing in the past couple of years, I was interested in trying to find a car that could fit into that type of racing. Probably the main advantage of CC/LeMons is that you don't need to have a competition license to be able to experience wheel to wheel racing and the experience of a truly significant amount of track time.

Things started moving when I met another PCA member who in passing mentioned that he had the perfect car that would fit the bill - a 1978 Porsche 924 that someone had given to him for free. The car was given to a teenager who did some hack fixes enough to get it running. He then promptly put it into a guardrail or a ditch, messing up the passenger's side front area. .

Another fender was added, and a junk headlight bucket. We shall try to get thing good enough to have the stock headlights working for the 24hr race. As you can see, creative engineering was used to open the hood after the wreck The car ran, sort of, and I was thinking that with $500 of headroom we could make a decent runner out of it and try our hand. A spare engine, front struts/brakes and other parts were also available. Hence Team Toofah Racing was born

Even for free, the car came with an extra engine and a pair of doors:

Well we had to trailer the car 150 miles from its current location to Phoenix. Once this was done, the team set to work sorting things out. The first problem was with the fuel delivery system. The fuel pump, while running, was not providing sufficient flow to get the car started. On top of that, the starter was not functioning.

After starting the debugging, it was found that the positive cable on the battery was basically completely gone but for a few strands. Some new positive/ground cables and the starter issues were solved

We ended up purchasing an OEM replacement / Chinese fuel pump for about $90 to solve the fuel delivery issues. Once we had fuel pressure, it was obvious that the fuel pressure reservoirs were leaking. Instead of spending our entire budget on new ones, we decided to delete these from the system, since we are manually controlling the fuel pump anyway.

We were able to get the engine running fairly well, after cleaning/rebuilding our spare fuel distributor. The original one would only let the engine rev to about 2500 RPM before cutting out. The surprising thing about the fuel distributor rebuild was that the unit sealed up perfectly the first time, even without using any shellac or other sealing compounds.

With the engine running okay, the next concern was for the brakes. Without going into too many sordid details on this, everything in the braking system was rebuilt/replaced, and but for a mistake in reversing the front calipers, things went smoothly.

The interior of the car was stripped (Anyone need any parts?), and a used Autopower cage was purchased and loosely fitted into the car. Since the car is still planned to be streetable in order to make it to the track/race, basic functions were maintained while removing unnecessary items (HVAC, etc.)

Safety items have been installed, including 2 cutoff switches per the new Chumpcar rules. Simple single pole switches were used, and since the alternator has been retained for endurance racing, a relay was installed to take the alternator out of the system and dump it to a 3 ohm resistor to prevent the diodes from failing.

Up to this point the car has been over at a business while the major items were sorted out. With the engine running and brakes working, and the car registered and insured, it was time to take it home to do the longer term work.

One of the first items to work on has been the electrical wiring and vacuum routing. The previous owner had basically hacked the entire electrical system up using a marine grade Romex type wiring. After removing most of this stuff, it was found that most of the original engine wiring harness was in acceptable shape.

Regarding the vacuum routing: I have used the Haynes manual and routed things per the diagram for 1978. Most everything has matched the diagram, but for one big vacuum leak just above the air flow meter. Here are some pictures of the current routing, let me know if you see anything amiss:

And here is the one fitting I can find nothing to connect to; if you know what is supposed to go here, please let me know

In true Chumpcar fashion, right now we are plugging this huge vacuum leak with:

We also modified the current shifting mechanism, creating our own homebrew short shifter. This follows the recommendations on the Clarks Garage forum, where you remove 8mm from the cast part of the linkage, and add 10mm to the stamped arm:

We also bought a set of Dunlop Direzza Starspec tires for the Toofah. It looks nice with its new pair of shoes

Next steps are to fix the alternator, add a Mazda RX-7 oil cooler, finish installation of the roll cage, and then start doing a lot of little things to get it ready.

Cheers, Keith
_________________
1987 924S SPEC car
Team Toofah Racing
1988 944 Turbo S

leadfoot · Posted: Wed Dec 22, 2010 7:35 pm Post subject:

to the ufo.
"crankcase breather"
Stu
_________________
1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

924RACR · Posted: Wed Dec 22, 2010 10:58 pm Post subject:

Clarification - is your car a '78 or a '79? If the '79, with the snailshell trans... you'd better get out there and make sure that trans can be shifted, before you get too far. Otherwise you'd better line up a transplant...

(I finished the build of my '79 racecar before finding out the gearbox was shot. Had to swap in a 4-speed, then got a 944 5-speed, and eventually the 924 5-speed with correct ratios)
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

KDJones2000 · Joined: 14 Sep 2010 Posts: 322 Location: Phoenix, AZ

Crankcase breather.... Thanks for this. I will look around and see if I can find it.

The car is a '78, and has the Audi 4 speed in it. I obtained a second transaxle (And a clutch, torque tube, etc.) from a 944 spec guy who had taken a cage out of a 924, but couldn't use any of the other parts. He actually has a snailshell transaxle as well, but I didn't pick that up as you need all of the torque tube bits to make it work.

This particular transaxle seems to have some issues with 2nd gear, but I need to get the short shifter adjusted correctly to see if it's that or if it is actually in the transaxle.

Cheers, Keith
_________________
1987 924S SPEC car
Team Toofah Racing
1988 944 Turbo S

924RACR · Posted: Thu Dec 23, 2010 12:13 am Post subject:

Phew, good.

Can't see the pics, but of course the crank breather isn't desireable for a racecar; we just dump ours (from the crank) into a Mobil1 bottle, and plug that intake hole.

I would be surprised that the trans actually has issues, internally; they don't usually self-destruct, that I've heard of. Of course, with a (non-snail) spare on hand, all the better!
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

KDJones2000 · Joined: 14 Sep 2010 Posts: 322 Location: Phoenix, AZ

Some other items that have been done so far to get the car prepared:

Front calipers and rear wheel cylinders were refreshed, along with new brake hoses, and master cylinder:

Front wheel bearings were refreshed. The current rotors are in good enough shape for break-in and possibly a race or two:

And finally, a hack job to try to cool down these non-vented rotors while on the track. Of course with the 95HP of the car, we should not really need the brakes, right?

Holes were drilled in the backing plates for the rear drums as well to try to increase venting.
_________________
1987 924S SPEC car
Team Toofah Racing
1988 944 Turbo S

KDJones2000 · Joined: 14 Sep 2010 Posts: 322 Location: Phoenix, AZ

Genadiers was kind enough to provide a replacement fuel inlet hose cover in order for us to pass Tech. We also glued a cover over the fuel level sender unit in order to isolate the tank from passenger's compartment.

Some more pictures of our Crapcan racer:

_________________
1987 924S SPEC car
Team Toofah Racing
1988 944 Turbo S

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

OMG, have fun with those solid discs in an enduro. . .and you better practice rear shoe "speed adjustments" as well.
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

KDJones2000 · Joined: 14 Sep 2010 Posts: 322 Location: Phoenix, AZ

924RACR · Posted: Thu Dec 23, 2010 11:11 pm Post subject:

Not sure if you're aware; there are apparently a few places that will re-line the drums with a competition lining. I believe Porterfield might be one. I'd go for the hardest/hottest compound they had. I believe you guys also get brakes as not included in cost, as safety equipment, right?
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Cedric · Joined: 27 Aug 2004 Posts: 2806 Location: Sweden

Rear shoes will probably be okay, they do not suffer that much wear, just have an eye on the adjusmnets. Why your there redo the master cylinder and brake cylinders at the rear. MOst import is to get good racing pads (and fluid of course) up front. They will probably last for many hours, if you done all the above and it dosnt work recheck your brake technique, short and hard, dont drag the brakes !.
_________________
1980 924 Turbo
www.instagram.com/garagecedric/

KDJones2000 · Joined: 14 Sep 2010 Posts: 322 Location: Phoenix, AZ

We are looking at buying Porterfield R4 or R4S shoes for the enduro, and yes brakes are basically free. For LeMons they are completely free, but CC has a slightly different formula to account for them.

We will have to thrash the car a little on the track to see how everything works. We are planning on a couple of dates in January and February to do this. Hopefully we can get everything sorted out then.

Cheers, Keith
_________________
1987 924S SPEC car
Team Toofah Racing
1988 944 Turbo S

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

So, need another driver/mechanic?

_________________
Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

924RACR · Posted: Fri Dec 24, 2010 10:58 pm Post subject:

Hmmm... I'll be in Yuma at the end of Jan/beginning Feb...

_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Grenadiers · Posted: Sat Dec 25, 2010 1:13 am Post subject:

Where are you thinking of testing the car? There is a Jan 16 track day at the Deming, NM track. There have been quite a few from AZ while I've been there. A bit of a drive however! And, if you need any parts, I have fenders, a hood, a million small bits, from a '79 n/a you can have.
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'83 944 Track car.
'88 924S Track car.
'89 944 Turbo
2004 Winnebago Vectra monster RV
2012 Jeep Wrangler
2014 Kia Soul
2001 Ford F350 powerstroke