My bud will be running a TSP 231/237 and AFR 205's. I am advising to get as close to 11:1 as possible, however there are 2 ways to do this. I think the first way below is better for a couple reasons...

.035 off heads (~5.8cc's, 60-61)
.042 head gaskets

vs

.042 off heads (59cc's)
.055 gm head gaskets

Both will give ~ 11:1

I am thinking the first option is better because of more optimal quench and therefore less chance of detonation, and less valvetrain geometry alteration.

Any advice is welcome! We (me ) just want to nail the setup and squeeze every safe hp from it.

 

Do you know, what your piston down bore is and bore of the block, and do you have 2 valve relief or true flat top. if so I can run some numbers and figure which one give the best swept cyclinder volume between those 2 combo's

 

They are the stock pistons/bottom end, that we will be notching. 3.896 I believe.

 

If I'm figuring this right your second option with 59cc and .055 gasket will give you total combustion volume 72.87 compaired to the 58cc and .042 of total combustion volume 70.32 and still be close to your 11:1 more volume means more horses, Hope this helpes and let me know what you come up with.

 

The 2nd group of numbers you mentioned above is not correct

more like 61cc and .042 (you said 58 and .042)

Again, the options...
59 cc with .055

or

61cc with .042