I was'nt just chuckling to myself about compression ratios, but also the advice about using thicker head gaskets and other daft comments!

I find it highly amusing that people who offer advice do so based on only their own limited experience which is often just one engine or at very best a few!! Thats simply not enough experience to go advising whats best!!

Regarding compression ratio's it's about using a C.R that is the best compromise for each application. That means suitability against fuel type, turbo type and of course power or more specifically specific power output per litre.

It is simply not the case that the higher you can run the better. If you all genuinely think that is the case then before I comment again please answer the following questions:

1. Why do you think Ford chose 8.0:1 for the focus RS mk 1 for a power output of 215bhp?

2. Are you all aware that the Focus ST is 9.0:1 for 225bhp but the same engine in the Focus RS is 8.5:1 for 300bhp and thats a 2.5litre 5 cylinder engine! (i.e. the ST is under 100bhp per litre! hence gets away with 9.0:1)

3. Are you aware Mitsubishi evo engines range from around 9.0:1 down to 8.2:1C.R as the power outputs rise on their engines? (Their engines are right on the det limit as std)

4. Why did Ford choose 8.3:1 for the CVH turbo engine when the N/A engine was only 9.5:1. Why not leave it at 9.5:1 for 130bhp?

5. Do you actually realise a lower compression engine generates MORE torque low down (i.e. off boost) than a higher compression engine?

Proper answers only please I'm trying to make people learn for themselves rather then me tell you directly!