Porsche 924S/931 "Gulf" race-car project

[PeepPaadam]

Thought I throw some pics about my track car project that I've been working on since December 2007. I bought the shell with roll-cage and paint-job done from my Latvian friend Alfreds. He raced it with 924 NA engine (built with 931 head and VEMS efi by me) and decided to make a new and more powerful track car of his 951.

Here are the specs of this car:
931 engine with VW flat-tops, K27/29 hybrid, Holbert/GTR intercooler, ITB intake, 630cc Siemens Deka injectors.
931 dog-leg gearbox, alloy rear arms, custom solid aluminium anodized mounts, Racers Edge uniball A-arm mounts, 951S brakes all around, BBS RS 16x8 and 16x9 forged 3piece wheels.
Dash is covered with black alcantara, I'm using stock gauges+LCD display for VEMS and two progressive shift-lights.
For some reason this car has late-style windshield.
Some pics:
In it's previous life with NA engine:










Custom rear suspension mounts and 951S caliper adapters made by me. BTW mounting bolts are safety-wired:


New crossmember made in order to mount oil cooler, Holbert/GTR intercooler and 951 radiator:



A bit rusty front discs:

and not rusty rear ones:


Oil catch tank:


Also finished and fitted fuel surge tank.







Intercooler in place:





Vacuum manifold for ITB's:



Rear wheels, since they are 9" wide and ET36 (also alloy rear arms), fenders need some "rolling" with 5kg hammer


Fitted the gas tank.


Intake plumbing complete, just need to buy some silicone hose connections:
 

[rob@vems.co.uk]

Loving that!  What's it like on the track?

[PeepPaadam]

I have no idea what it's like on the track with the new turbo engine, I've driven it only once when I was building a modded NA engine and installed+tuned VEMS on it. It made 121 rwhp on NA form and could have used a bump in compression ratio to really live up to the task (it was around 10:1, could've been around 13:1). Stock 924 NA engine makes 125hp at the flywheel.

I bought just the body shell that had paintwork and roll cage and I'm in the finishing stages of driving it as soon as the snow disappears.

[z0tya]

Nice the intake plenum!
Audi B group style. The cyls get equally air as much as possible.

[PeepPaadam]

It's been some time but the car is running now very good with 0.9 bars of boost making around 270-280 hp and is super-responsive between gearshifts and basically there is no lag in corners when revs are 4000+. And it spins 235/610 R17 slicks so easy on 3rd in corners that it is scary  Of course, it weighs around 950 kg's too, that makes it much easier.
Went to the track first time on Sunday and car held up just fine for around 20 laps+20 laps in a row. No oil pressure loss in corners (I was on slicks), no overheating etc. The more I drove the faster the car (or perhaps the driver) got. But I was still driving too slow even to warm up the tires good enough.

No wings or splitters yet but I'm planning some aero "development" in winter.

Few pics also:

First corner taken with the car and with dead cold slicks it was like that (applied too much throttle with 2nd gear):