I Need New Forged Pistons - 308GTSi QV

It's finally happened. After a very long relationship with my turbocharged Koenig engine, the pistons are suffering metal fatigue. I started getting a very mild misfire and low vacuum readings. A teardown showed that the top rings had mostly disintegrated, signs of crack fractures in the dish tops.
Alas, it's time for new pistons and lots of advice from you engine builders out there.

I think I need a set of forged pistons with a higher compression ratio of 8.0:1 instead of the current 7.0:1. This is because I am running a SDS type digital electronic engine management system that allows me to control both ignition advance and fuel maps and no longer the original Ferrari electronic distributors that had their advance curve disconnected for safety. With new FORGED pistons, I figure I can go up to 8.0:1 CR to enjoy better low end response on the rev range.

My questions are, what do I buy and who can I buy it from? I am based in Singapore not the USA and this makes buying custom parts a little of a challenge.

I was thinking of getting a set of 8 pistons from JE but this is the first time I am buying pistons and they are custom pistons as well. On top of that, I am hoping to raise the CR from 7.0:1 up to 8.0:1.

So gentlemen, any advice or suggestions are appreciated.

A parts guy looking at the pistons thought that they were from a Honda Civic B16 turbo engine. BTW, my piston bore size is currently 81.4mm and the material looks like it is made from Hi-Cast Alloy and not forged but I cannot be sure. The pistons look like standard Ferrari pistons with the dish milled doen slightly to lower the compression. My engine with the turbo should be producing about 700BHP which is why I am looking toward forged pistons since I have to buy a new set of 8. OUCH!!!

 

The car and engine was built new by Koenig in Germany in 1985. I bought it in 1998 from the original owner. It had 2000miles on the odometer and was hardly used as it was a collector's car.

I did not commission the build and the engine has never been opened, only serviced since 1985.

From what I can see, the engine has a custom crankshaft but uses standard profile camshafts, piston rods and standard but milled pistons to achieve the 7.0:1 CR. The piston dish has been milled down and the crown is thinner than the standard Ferrari piston, so that a lower compression can be achieved. The liners seem to be original and not iron-liners.

I made a mistake about the original piston size, they are 81mm, I am looking for a slightly oversized piston for this upgrade.

I agree with you guys that it is probably detonation as I have been cranking up the boost on the tubocharger to 1.7bar but there is a overboost cutoff protection, and think that it is metal fatigue more than anything else. I could be wrong.

I tried calling Venolia and JE pistons from Singapore (it has to be 2am my time to talk to technical assistance) but have had not much help as they are not used to dealing with someone across the world.

The problem is, that I want to get custom pistons that are forged (for better strength) and slightly different (higher compression) from the already non standard Ferrari pistons installed. They were beautifully milled down and have lasted over 20years. I have been redlining the engine frequently and I think the basic specs and engineering were done right as the engine has lasted well.

I did replace the original Rajay turbo with a Garrett hybrid turbo but it has been running well for a year until the top ring disintegrated.

Any help with a contact with JE, Venolia, Weisco or any other quality forged piston manufacturer who is willing to advice and help me with a quick and cost efficient turnaround, will be greatly appreciated.

Am really grateful to you men out there who take the time and share your experience with other enthusiasts. You can only imagine how difficult it is in Singapore to get a custom built car of over 20 years vintage to keeping running and get parts for. I'm a sucker for punishment!

 

Thanks for the suggestion on Norwoods. Got an almost immediate reply and they are very knowledgeable. Such a pleasure to deal with professionals. you guys are the best!
ctk