Compression Ratio

[MK2Ed]

What is the highest (though practical) compression ratio I can have on my engine with pump super-unleaded?

 

Cheers

E.

[V8ian]

I run 11.5-1 on optimax or similar, BUT the engine is all ally, which helps against detonation and I run mapped ignition and fuel injection, Although I have a friend who runs 12-1 on a pre X flow without too many major dramas,

Static calculated compression can only be used as a guide for actual compression ratios as Overlap on the cam will also affect how much compression you have, by allowing some of the gasses to escape while the valves are still open on overlap and the piston is rising on the compression stroke. Somtimes seen as reversion as the fuel been blown back thru webbers on full chat

Ian

[MK2Ed]

Thanks Ian... If you live norf of Watford, just you might live not far from me, in Park Street...