3.6 964 Rebuild - I might need new cylinders/pistons help please

[JonT]

My case is done at Ollies and being shipped to my builder however the cylinders and pistons are still a question mark due to some flaking issues on a couple of the cylinder walls and wear on the pistons. If I need new cylinders/pistons does it make sense to go to a 3.8 size? There would be no other changes to the engine since my heads and valves and everything else is done and ready to be assembled.

Is the power increase justified or negligible with just the cylinder/piston upsize?

Thanks

[Sboxin]

We sent ours to EBS and they suggested the increase to 3.8 size because they had a set of JE pistons on the shelf for a good price and they were reconditioning the cylinders anyway. IMHO, you probably won't notice a butt dyno difference - however, with a freshened engine you may notice better gety-up . . .

I would recommend you talk to EBS and send your cylinders and pistons for evaluation.
We also reground the cams to Webcams 20/21 higher torque cams - EBS valve springs - stock intake - headers - Wong Dyno tune = 257 RWHP 237 Ftlbs rear wheel torque

Regards,

70+ race hours = still strong 3.8L

[Jeff Alton]

Price out the options, make a decision. Some times the bump in displacement is a wash cost wise.

What work did your case need at Ollies?

Cheers

[JonT]

Thanks. I have the webcam supersport billet cams, rockers reconditioned/reground, anodized lower spring seats, valve stem seals, titanium retainers, Aase race springs, rods rebalanced.

Stock intake, 993 headers. May go to a better header if $$ allows for it.

Ollies needed to clean up a couple case through bolt holes (weld and regrind). The main bearing journals needed to be cleaned up a bit too as they were on the outer limits of the tolerances. Prepare the case for Gt3 oil pump.

[3rd_gear_Ted]

Suggest a fuel pressure regulator, your gonna need about 65 psi @ idle to get the WOT needs of your injectors for a 3.8 set up