Why is lower compession better in a turbo?
Turbo or supercharger, which is better?

 

its not better really, but it makes it easier run more boost because its
less prone to detonation.

 

Is it easy to lower compression in an engine?

 

Yup, change the pistons and headgasket.

 

Any certain pistons you recommend?

 

JE Pistons are good.

 

the more cylinder volume you have, the more air you can fill in under boost ... downside is phase timing, i.e. the camshafts you use, intercooler piping size and size of turbo, size of TB and manifold runner diameter, etc. ... all this relative to motor size

Many people just piece stuff together with no understanding how things work.

I use as low as 7.0:1 compression and if I can go lower I would ... on a FWD anyway.

Greg

 

When planning a turbo engine where do I look or who do I employ to help create this torbo system? Are there any sites or specific books which will help in this building of the sysytem? Thanks

 

The reason for lower compression in a turbo is that it increases the dynamic compression ratio. In simple terms a 12-1 NA engine at 100% volumetric efficency is 12-1 dynamic. A 8-1 turbo at boost to increace the VE to 150% is 12-1 dynamic. And, yes, cams and chamber design change the dynamic compression, but this is a simple overview. Compression is just how many times you squeese the volume of air in the cylinder from BDC to TDC.