Just got the car back on the road after Lowering C/R feels more torquey.
Obviously the main reason for me lowering is to allow more boost, but i remember years ago having massively reduced C/r seemed to give better low end feel (more torque) ?
Discuss

 

The correct CR will give the most torque.

any lower an you get less torque (cause PCPs are too low)
any higher and you get less torque (cause PCP's arrive too late)

 

how do you work out the correct c/r?


can of worms time

 

engine testing will tell you whats best!

 

It increases as RPM increases

 

you sure about that chip?


It increase as cam duration increses......

Alex

 

It decreases as boost increases

 

the only way is to test

 

Lots of true statements in this thread.


Complicated business Lee

 

Torque is a function of cylinder pressure and the throw of you crankshaft.

So the lower the comp typically the worse the engine performance off boost.

Hence many manfuactures using high CR and LOW boost so that the engine remains torquey at the low end and retains fuel economy.

Alex