Im in the middle of ordering all the parts that i will need to rebuild my engine.Everything will be sent to a professionnal builder.It will also be the last time(4 th)...if it doesnt work i will just quit :ack:
Engine was built for n/a purpose and now i got a blower.Would it be a good idea ,while im there to change the pistons or heads or maybe both to have a better, more reliable/suitable and powerful setup.

Im keeping the block,callies compstar 4 inch stroke crank, callies compstar 6.125 inch rods and custom blower cam(see sig).Will be looking at 10:8:1 cr.Will add some tool steel wrist pin,Hellfire rings gap for blower application, Johnson 2116lsr lifters and all new bearings everywhere.Will upgrade to a 3.4 pulley to push 12-13 psi with a looney twin pumper fuel setup that i already bought.But what about the rest ???

Option 1:
-Keep the Wiseco flat top -3cc valve relief and upgrade to some nice AFR Mongoose 230cc small bore heads

Option 2:
-Keep the PRC stage 2.5 ls6 heads but change the pistons...what model/specs ????

Option3:
-Change both heads an pistons...what model/specs

Option 4:
-Keep everything because it should work ,add a thicker cometic gasket to get 10:8:1 and be happy with it... just a quality rebuild :smash:

 

Option 5.

Sell the PRC heads and get something else.
You don't need $2500 heads to make power with boost.

 

Agreed. A pair of <$200 stock 317 castings would work fine. Still may need to change pistons to a dish in order to get the compression ratio down, or just use a stock LQ4.

 

The largest chamber a PRC 2.5 LS6 head has off of the shelf is 64cc, but its most likely lower. Even if he has 64cc heads at 10:8 and goes to something like the CNC ported 317s from Thompson or PRC 2.5 LQ9 heads from Texas Speed, he can get his compression ratio within an acceptable range for boost and not have to spend a bunch of money out of pocket if he sells his current heads to cover the new ones.

Since unported 317s have been ~1100whp, I'm sure the CNC ported ones will be fine.