thanks suba..maybe if i explain myself better ...i am trying to grasp which would be the best way to achieve a good 1/4 time all i know is that the higher comp gives a little more off boost i am not sure about the difference on although i would like to know..i can understand how it would be better to have slightly lower comp in order to run higher boost /bigger turbo in order to use the turbo to make the bigger power...my interest is more in which way you would achieve a better result over a small distance like the 1/4..by using higher comp smaller quicker spooling turbo or a lower comp bigger turbo more boost...
do you see what i would like to understand better? it would be nice if rather than just getting an answer i could get an explanation...also what are the advantages and disadvantages of higher comp say 9.1 when on boost... can anyone fill my spongelike mind with a good laymans terms answer
OK, I wont write an essay for you. There are plenty of books on forced induction tuning / mapping that you can buy if you want to read in detail.
High compression ratio = good performance off boost, smoother transition onto boost, and better response on boost. However you can't run as much boost without detonation
low compression ratio = rubbish off boost, but you can run big boost when the boost thumps in without detonation
For a 1/4 mile the car should never be off boost. All the big power drag skylines may well be road legal, but would drive like an utter dog on the road - low compression ratios with fat head gaskets, and no power below 5,000 rpm. However for a 1/4 up goes the rev limit, and the car gets launched at 6,000 rpm....you can get away with this as there's the AWD drivetrain.
With FWD I can't imagine a 6,000 rpm launch on road tyres in a car with 400bhp is going to be all that easy...
