Porsche Enthusiasts Club Forum

spotted a 924 turbo race car project on ebay, i quite like the idea of the 924 turbo, rare, lightweight and a good chassis, and i have seen it fail to sell on ebay a couple of times now for not a lot of money. i was thinking of doing some racing in it while the 944 turbo is being built.

does anyone know much about the car, and if its worth looking at?

also how tunable is this engine without going crazy, dont know a lot about the 924 turbo, but would be nice to add to the collection lol.

cheers
nick

Hope you've got a spare few hours Nick!

viewtopic.php?f=25&t=13106&hilit=924+turbo

Yeah, seen this car on Ebay a few times.

Alastair Kirkham of Porscha-recycled used to race a 924 Turbo. It's a challenge as IIRC they moved him into a tough racing class because of the turbo. He was making around 200-210hp with an intercooler I think and I remember him saying the car was great on high speed circuits like Silverstone.

Definitely would fit an intercooler. The cars are marginal even at 10psi boost with high intake temps IMHO. Don't know what Porsche were thinking running without one, although I suppose it was still early days back then for turbo road cars.

The bottom-ends, if in good order, are pretty much bulletproof - forged steel crank with rolled radii journals and forged steel con rods with 24mm piston pins. The closed deck block has ridiculously thick walls so is as rigid as it gets.
The arguable weak spot is the pistons (as with a lot of turbo engines) as they are cast, and top compression rings can break with any detonation. Obviously this means tuning is critical to avoid lean condition etc.
It would be advantageous to fit a AFR gauge and possibly a knocklite/link. Fuel system is good for 240-250hp if its in good operational condition - its the basic K-Jet CIS.

S1 is simplest with distributor based timing with a vacuum/boost retard box and both S1 and S2 have a boost operated WUR.
S2 has digital ignition timing control same as 924 Carrera GT.

I think its possible to get weight down to 930kg, so 210hp, which is easy to achieve, should make for a pretty quick car. Upping the boost a little should net a bit more, but standard turbos end up running off the efficiency map. If you have a spare 951 250hp turbo you can swap the turbine housing for a #6 S1 housing and then up the boost to around 1 bar, netting around 240-250hp.

EDIT: Just had a look and the car is an S2 so has better ignition timing control.

Has 'safer' ignition timing control, but also non adjustable!

Not been on here for a very long time but I, too, saw this on the bay and wondered about whether it would be a good buy or not, if it came cheap enough.

I have exchanged e-mails with the seller and the engine was rebuilt some time ago by a "Nick Bentley Motorsport" but I have never come across them, anyone know of them. It supposedly runs well and has done a track day in the last 12 months.

I'd want to use it in something like CSCC "Future Classics" and do a few "sensible mods" but I'd need to get a specialist to do those for me as I'm technically incompetent! It would have to be on a budget, though.

If I assume that the engine is basically sound, seeing as it has supposed to have survived the track day, can anyone offer some ball park figures for the cost of some straightforward upgrades to include an intercooler. I know that this is a "how long is a piece of string" question but what would be involved (in simple terms) and how much would it cost to get an engine that delivers a reliable & bullet proof(!) 220 Bhp or 250 Bhp race engine? I have seen Jon Mitchell post on here, can Jon (if he is reading this) offer a ball park menu pricing????!!! I won't hold you to t, just need to get an idea.

Thanks

Andy

944 intercoolers can be bought for a tenner on the right day. Making your 931 fit around one is labour intensive though - you cant simply buy the part that makes it work.

Id say £10 for intercooler and £10 for front end metal work which itll fit into (the days of front end repairs and high value repair parts has long-since passed), but I cant put a price on the time itll take to make it happen.

Steves done it, so Im sure that he can offer an insight.

I believe Steve has a spare 944 intercooler 'kit' for sale? Was dyno'd at ~197hp at standard boost.

For sale turbo intercooler kit for sale removed from my spares car. A little Heath Robinson in its approach but delivered 198bhp on the dyno a year ago with stock 0.65bar boost. More may be available with the right tune and boost controller. It may require some tweaking to fit your car. It currently resides with in Scarisbrook as it was going to end up on another car.



It comes with adapted 951 IC, all the piping, hoses and cone air filter.



Looking for £60 collected. A 951 IC would cost circa £50 on fleabay.

Alternatively you could buy a full 951 front end and graft it to your 931. Not a massive job and will look more OEM



Then the next issue is finding room for the pipework as its all a tad tight. Watch this space. Mines going back together again over the coming weeks.

like any car of this age im pretty sure there will be other items that need attention to ensure the car is reliable and up to going round a race track! first of all the gearbox needs to come out to look at why its popping out of gear which will likely be detent ball bearings/springs which will require a strip down. he also states brakes need a good service.

i dont think any porsche turbo can be done on a budget lol, parts prices are pretty horrific on there own! certainly a lot of 944 turbo parts are pretty silly and the 924t is a rare beast and so parts could be hard to find.

i am tempted by the car, but i feel it could need a few quid spent on it to make it right.

nick