hosrom_951

You are running 17psi on a stock engine? i heard that 15psi (1.0bar) is the Max you should set the boost before blowing a head gasket. Well, i am convinced and chips and wastegates as a start, and boost and A/F gauges are to come before the modifications to be done.

ewainwright

My understanding is that anything over 18 psi requires racing fuel and retarded timing

However, a larger turbo requires larger injectors (55 or better), 91 octane and an aftermarket engine management to run 18 psi. I monitor my A/F ratios like a hawk.

I will get in trouble for this but cranking up the boost on the KKK turbos may be where you got the 15 psi from as they can become heat sinks and seriously heat up the charge (do a SEARCH)

Generally, detonation blows headgaskets. This is usually due to poor A/F ratios (as well as overheating). Aftermarket MAP (I am not recommending this (use SEARCH)) or MAF along with chips is necessary as the old barn door just won't cope

Jaak Lepson

All I have is a Lindsay Boost Enhancer and Weltmeister chips. I still keep chirping the rear wheels in 1st and 2nd gear!!!! Previous owner of the chips had 243 RW/HP on a stock setup.

Jaak Lepson