just ran some numbers in a compression ration online.
bore=4.00
stroke=3.625
head chamber=66cc
valve relief=28.5(w2w custom mahle piston)
gasket thickness=.054
and it gave me a compression ratio of 8.07 to 1
the heads are afr 205's. is that a good ratio for the 6.0 block and a pt88 turbo?tell me what u think.
thanks

 

What gas you going to be running it on? Whats your intercooler setup?

 

93 pump gas, a2w intercooler

 

Compression is a bit lower. You will be able to running more timing safer (less cylinder pressure with lower compression), but if you bump the compression up (9-9.5) you will see a huge increase in your mid-range.

 

to make big horsepower 800 rwhp + is this low enough compression ?

 

I'd keep your compression around 9.0:1. What are you building the car for?

That is what I run and see numbers semi-close to that. I'd strongly reccommend running some higher octane fuel to be safe.

As for 800rwhp, 9.0:1 is a good ratio to rely on. Hope this helps

 

building for mostly strip car , but like to be able to drive it to work or to cruise around on the weekends with no issues. i would probably use a mix of higher octane at the track to run the higher boost level.

 

so w2w your saying its better to have 9.0-9.5 compresson for better mid range?why will the 8.x compression harm mid range?wat compression will i have on a sock ls1 block with stock internals and gm 6.0 317 heads(72cc)?

 

The lower the compression, the worse it is going to drive on the street. If you are only going to drive it alittle, wehn I would go with 9-9.5. If you were to drive it more, some places it is a pain to get higher octane then 93.

The thing with raising the compression ratio is that the cylinder pressure go up. IF you can get cold air and or higher octane, it is not a problem for high horsepower. You can run the pump on it, but you will run less timing. I have done a "back to back" dyno runs. The higher compression will bump the mid-range, but will not increase spool.

I hope that makes sense, I am a bit tired after work

 

This buds for you nicely put

I'd rather spend twice as much for fuel then have a problem down the road because i didnt want to pay $5-8/gal for fuel. You can order VP Racing 55gal drums delieverd right to your door, like i do. The smell of the fuel is simply amazing. Turbo blue 100unleaded or MS109 is what i run. Love em both.