Juha, I remember you from when you were on the 996 GT3 forum. I have seen air cooled Cars running in the Chicago PCA club race at Road America. 800 horsepower and faster than everything, BUT I was told that the two guys who drive them are great friends and tough compeditors. The cars ran in GTA (run what ya brung. ) Some of the other drivers from California who race with them said when they turn up the boost to 800 horse it had bettter be a short sprint race because they usually blow up in any enduro. Fresh rebuilds multiple time per season. I only wanted to question your belief that it can be done with the word reliably in the equation.

 

Reviving an old thread... The car is ready for big power!

I need 600hp, reliable, trackable engine. Want to stay aircooled.

1. Take my NA 3.6 engine, throw away the heat pump (supercharger)
2. New parts:
- Crank GT3?
- Conrods (Carillo, Pauter?)
- Pistons+cylinder 3.8 (or 3.9) Porsche MS or ?
- Heads (use NA heads with twinplug arrangement?)
- Camshafts (which cams?)
- Camgeear
- Valves (which valves?)
- Valve springs
- GT3 oil pump
- high flow injectors
- Seals, bolts, bearings etc.
- Some machining

That's a good 10-12k there..?

3. Assemble engine (will leave this to a professional) 2k
4. get some proper turbochargers 4k
5. Fabricate headers and rest of exhaust (DIY but as much copy of proven concepts as possible) 1k
6. Fabricate intake piping 0.5k (use my existing 996 70mm throttle valve)
7. Buy another set of GT2RS coolers and fab a good IC (DIY) 1k
8. Add necessary wiring to engine harness and motec harness
9. Assemble everything
10. Tuning on dyno 1k

So, that's about 20-22k there...? What am I missing (big items)?

 

I think you are a little short on the budget...

- Crank GT3 - $1500
- Conrods (Carillo, Pauter?) - $1600
- Pistons+cylinder 3.8 (or 3.9) Porsche MS or ? - ~$5000
- Heads (use NA heads with twinplug arrangement?) - ~$2500
- Camshafts (which cams?) - ~$1000
- Camgeear - ~$350
- Valves (which valves?) - ~$1200
- Valve springs - ~$600
- GT3 oil pump - ~$1500
- high flow injectors - ~$300
- Seals, bolts, bearings etc. - ~$2000
- Some machining - ~$600

Just here you are looking at about $18,000 to $20,000 in parts. I have just about bought all of the above for my engine so I know exactly what this stuff costs....

 

Thanks Steve!!

Allthough my prices were in Euros... so 18k usd is roughly 13,5k Eur and given I can use my NA heads (with some machining), the figure is closer to 12k euro.

But more than the budget, I would really like to know which parts to use and where to get them from?

 

I am going through this now. I am leaving out a whole bunch on that list. including heads, crank, & oil pump. You might want to consider 9Meister billet twin plug heads. Hydraulic lifters may not be a good idea if you go with an agressive cam - so throw lifters into the budget. If you do all the work yourself you might get it done for less than 20g USD.

 

I was told that the NA heads are perfect for this as they already have twinplug arrangement. Just some machining (flame rings + valve seats + ports) and you have perfect heads.

I would like to do the work myself, I have built several BMW engines (and have even successfully raced them for years) so I know in engine work it is all in the details (cleanliness, torque specs etc. etc.). I also have access to factory tools (timing, block assembly etc.) so that would not be an issue either.

But I am torn between buying a used 993 turbo engine to begin with or tear into my NA engine. A used turbo engine is about 15k euro here. There is a lot of parts that I don't need (p+c, cams, turbos, intercooler, ECU etc.) because they would be changed in any case but on the other hand If I start with my NA engine, I need to get some turbo specific parts such as the intake manifold etc.

If I buy a used turbo engine, I could put my current engine with the blower on the shelf (and get a lightweight narrow pre-80 chassi for it later...hehe)

 

Not really, the best heads for your app is the turbo heads, combustion with these takes place outside the sealing area, so it get less affected by the combustion pressures within.

 

+1 from what I understand. The turbo p&c's and heads are different to have the combustion area inside the head to decrease strain on head sealing. There was a thread by someone a while back using NA heads and P&C and it will work (I believe the na heads have better flow?). But may not be as reliable.

 

I have got a complete rebuilt 993 tt engine with a lot of gt2 parts on it and the very rare secan intercooler! new mahle motorsport pistons and rings, pauter rods, new motorsport (stand'97) cams ,solid rockers, boat tailed cassings, mooned cylinders , rebuilt k16/24 turbo's ,motorsport manifolds !

Also have the gt2 evo motorsport 6speed gearbox

for the right amount of Euro's it might be for sale

 

 

Flipo,Love that engine!!!Cheers.

Juha, Got a nice set of Mahle 102mm Turbo P&C's, if you go that way let me know,cheers.

 

PM sent!

 

pm replied

 

For a reliable track engine just keep it simple. 3.6, single plug, built internals, evo cams, proper head work, A28's and you can even keep the stock headers. Worked for me and nothing will pass you in straight line at the track, at least in my humble experience.

If you have the cash then I would start the build planning on ITB's & Motec and the rest will fall into place

 

spartans right, you can keep it relatively simple, make good power and stay reliable. saying that my gt2 racer had twm throttle bodies loads of expensive parts and motec so im a hipocrite i guess?
anything over 550hp and i struggled to get good traction on twisty tracks even with 31/71/18 slicks on.
i raced it this weekend with a 390hp 965 motor after i put the gt2 engine in a cayman. slower lap times but much easier to drive lap after lap.
so unless your tracks are like our silverstone or spa with nice wide corners, smooth surface and plenty of straights i'd stay below 520-550.

i saw some 9m heads when i was on there dyno last week, they look very sexy!
i use carillo or pauter rods, you cant go wrong with tried and tested! get a quality intercooler as well, nothin worse than setting your suspension settings to make it handle for say 600hp then you have 500 or less after 20 laps and then a different animal to drive!