280 zx, bob sharp racing

[henning]

I`ve just purchased a 280 zx -82.
The car had been turboconverted in 1984 by "Bob Sharp Racing" in USA. When the car arrived Europe the owner blew one of the pistons at the autobahn on his way home. He changed the piston and reduced the boost. According to the boostmetre in my car it now only produce about 4 psi...
Is it possible to increase the boost without smashing more pistons??

 

[Mr.F]

1. You need to know what pistons are in your engine. They should be of the dished type and ideally you should have the P90 type cylinder head. For bigger boost, it is preferred that the turbo style pistons are fitted.
2. Do you know what boost was being used when the piston was damaged? Obviously this was outside the safe parameters of the rest of the system. The engine is probably under-fuelling at high boost, or the ignition advance is not being retarded.
3. Is this an original turbo engine - if so, then there will be a knock sensor fitted? Is this still functional and working correctly?

Really, you need to answer these questions before you take a chance on raising the boost again, and only then can you decide what a safe level would be. My rough guess, if this engine is based on an original turbo engine, would be no more than 10psi without additional provision for boost fuelling. I'd be interested to see some pictures of the installation or to look at the car for you if you are ever in the Essex area, but I assume autobahn references mean that you are elsewhere in Europe....