Im trying to decide on what heads to go with?
as well as what kind of power could i possibly be looking at?
im shooting for a mid to high 10. sec range set up.

fast 92/92
TSP 1" 7/8 longtubes
TSP true duals
ms4
afr 205's or afr 215's

on a 1998 ss m6
thanks in advanced for everyones input.

chris

 

looks like a pretty solid combo so far.... afr, etp, trickflow.....all heads to look into......honestly though you wont see many ls1's running 10's on a stock bottom end and stock weight...so just dont be disapointed with low 11's or high high 10's....my guess is if you go with a ms4,true duals, and top of the line heads, you probably will be sitting around 470-500whp ....dont count on 500 though bc few ls1's have ever hit it with a stock bottom end, you will need the best of everything....and high commpression plus big cam, meaning you will have to flycut your pistons.....
stock weight you need about 500 to hit 10's by the way so if you want tens you probably will have to flycut pistons too....that or shave weight.

 

also search terminator heads, they have a head/cam combo they claim hit 522whp...if you want to hit 10's theres an option....

 

sounds like a pretty stout combo but youre going to need a new rear if you hope to hit it with that combo.

 

is there any way to get around fly cutting pistons when running a ms4 and afr 215's?

 

raising the deck height with taller head gaskets will create clearance but it will also lower compression. Or get dished pistons.

 

Combo sounds great!

 

hmmm i am going to build a similar combo, but with budget prc heads, probly need a good gear, i have a 9 inch 4.56. i am at 3300 lbs now.

 

i was thinking the AFR heads would clear the MS4 with a stock gasket....barely...

call TSP...they should be able to confirm.

running the TFS 215s or the TSP 215s would allow for better clearance to to the redesigned valve angle.
that reason alone is why i'd chose those over the AFRs

 

MS4 is on the ragged edge of ptv clearance with stock valves and heads. You should definitely check the ptv with some clay. You will most likely need to flycut the intake side, and maybe the exhaust as well.

 

i wouldnt be going with stock heads and valves im either going with afr 205's or 215's. would there be any clearance issues with those heads?

 

What I meant is, if it is close with stock heads and valve size, it could likely be worse with aftermarket. The only way to know is to measure.

 

AFR 205's usually have more clearance than stock heads, at the 'as delivered' chamber size. That said, the only way to know for sure is to measure. Any clearance grinding you would need should be minimal.

Ideally, you should be milling the heads to 59cc's for that cam and running a thin .040" to .045" gasket with appropriately clearanced pistons.

 

like said previously....to improve piston to valve clearence, flycut, dish pistons, thicker head gasket are your choices, or going to a 1.6 ratio rocker arm which will ...in a nut shell ...make your cam smaller so its not a good idea....and for the people asking if afr 205 or other heads will clear....it depends on the cumbustion chamber size, not just the brand of head so check that......and like also previously stated, the only way to truly know and be 100% safe is to measure piston to valve clearence....always always check.....and me personaly, i dont know which heads, and which size of those heads clear what size cam off the top of my head, maybe somebody else can help.....if not dont underestimate your resorces, you can call or email the company that makes the heads, or a cam company, or texas speed or another parts distributor. hope that helps

 

my best guess though to be safe is with ms4 and afr 215's would be to have a 67cc head or bigger, but your still best off talking to somebody whos an actual professional because you could easily get 72cc or something to be safe, but you dont want to do that, you want to get the smallest possible cc so your compression is as high as possible and still have room for the cam

 

Just man up and cut clearance for the valves. There are several threads around here with pictures of what is required.

Putting all those parts together with large combustion chambers and thick gaskets is a bad idea. You would be better off with a little less cam and the proper setup. Cutting corners here will undoubtedly lower your final output. Attention to detail sets the average apart from the exceptional, and you're trying to squeeze 500rwhp out of 346ci.

Think about it...