700-800hp Ideal Compression Ratio

[GDZ1LA]

i have finally made progress on my circut race engine one problem tho.. comp ratio..

specs are

87mm bore 87.8mm stroke 3130cc hks rb26 pistons 14-15cc? 0 deck clearance 1.3mm muilti layer head gasket

head 66cc (current) but using large overlap apexi cams.

i calulated it to be 9.7-9.8:1

turbo is t78 33d and aiming for 700-800hp max prob 650hp nominal.

i can remove some cc from intake squish area. what do you suggest i drop comp ratio too?. i using 100ron.

and 8000rpm all good? all been balanaced crank collars etc too.. oem 26 pump.

what are some other engines compressions making this kind of power..

head is off so now is the time to act.. 9.7 is high but will large overlap cams reduce this enough?

[Adriano]

Depending on the fuel you plan to run(to make 800hp), i would say to make the sort of power you are after, you are looking at running at least 1.6 bar. I would recommend no more than 9.2:1, however it seems that you have completely the wrong pistons if a 1.3mm headgasket give you such high come, can the pistons be decked safely?

[STATUS]

i will check the T78 Rob used as it maxed out at 440rwkw, well short of your target (i reckon you should look at a GK) and was too responsive full boost at 5k.