Going to get my brand new 383,fully forged stroker crankshaft, kb reverse dome pistons .030, eagle stage 2 longer rods,arp main journal bolts, lt4 heads/intake, hotcam kit . my question is the guy said the reverse domed pistons were used to reduce the comp ratio, said it should be about 9.5:1 i believe, are these pistons going to be suitable for s/c applications, he said they are hyperectics and i said no s/cing for me then, and he said that he built it with low comp and encouraged me to think to get a s/c setup. just seein what you guys can tell me from this.

also what harmonic balancer do you guys recomend to help the engine out, and what "key" do i need? thank you.

 

Im kind of new to S/C so take this for whats its worth. Hyper pistons are okay as long as you play it safe with the tune and with boost. From what Ive read the normal CR for a S/C motor is about 9:1 so you are pretty close. If you get the big chamber LT4 heads you could bring it down to that. If you arent sure about S/C then you need different pistons. 9.5:1 on an N/A motor would be no fun IMO

As far as the balancer Im going to be using a keyed ATI damper. The LT1's have a half key way in the crank. This damper will allow you to use a full keyway and keep the balancer fom turning on the crank

 

ttt, anyone else on this

also will i need a 350 harmonic balancer or a 383? ive searched but that never came up thanks

 

Hyperuetectic pistons are not recommended for boosted or nitrous applications, but as mentioned above, even a cast piston will live as long asit's not subjected to detonation so tuning is key. 9.5 to 1 is okay up to around 10 PSI or so but you may wnat to play it safe with the hyper pistons. DO not get the LT4 heads they have a smaller combustion chamber and will raise your compression ratio. The ATI Superdamper is the damper of choice for boosted aplications and is even available with a big block hub thickness, however the big block hub would probably be overkill for your application and not necessary, I would run the ATI damper and it is already keyed. If the crank in your engine isn't keyed you could run into trouble though.

 

there is no difference between dampers for a 350 or 383

 

i thought I saw that someone offers the LT4 heads with a 58 and a 62 cc chamber. Maybe it was AFR

 

AFR does offer custom castings of LT4 heads that have chambers up to 72 cc, they're pretty pricey though. The stock LT4 castings are 54 cc.

 

Gotcha