I know forged is the way to go as far as boost goes and its going to take me some time to build a forged engine. I have my turbo on the way an I was going to put it on my 327, it has Hypereutectic Pistons with 9.6:1 compression. I was wondering how far should I go with boost on a intercooled setup?

Also I was thinking about going with some 74 or 76 chamber heads right now I have 64 chamber trick flow heads.

How far will this lower my compression and how much punishment and boost can these pistons take if properly tune?

 

Hyper pistons are plenty strong and will take all kinds of poewr. Theya re unforgiving to severe detonation ( tuning mistakes). Hyper pistons also run hotter requireing wider top ring end gaps. Wider that yours are now. Your piston would probabily out live ya if the motor was tuned right (AFR)
and sufficiant octane fuel was used and the ring end gaps were opened up more . This would require dissassembling the motor.
With intercooling you should be able to run up to 7-9psi boost with your pistons on 92+ pump gas.
(WITH A PROPER TUNE) this is the key, its during the tuning phase you're bound to run into trouble and stress the pistons.
As your motor sits now, considering the likely tuning headaches, I would limit the boost to 5psi.

racing gas will allow more boost with good saftey but the ring end gaps still need to be opened up.

Either way ultimately you'll end up tearing down the motor.
You can do it now (and open up the ring end gaps) or after ya grenade it. your choice.....
5psi or less for now. use conservitive timing and high 110+ octane race gas during the tuning phase. (cheaper then busted pistons and cracked cylinder walls)

 

So the ring end gap need to be open. How do I open them just file down the ends? How far open do they need to be? Are there special rings just for boost I can buy? If I was to lower my compression to lets say 8.5:1 and have the ring gaps open could the pistons handle 15psi?

 

The various piston manufaturers have special recomendations for blower/turbo/nos applications.
Keith Black hyper pistons need the widest gaps.
All hypers need wider gaps for power adder applications.
So do forged pistons by the way.

If the N/A gap is .018 run .026" if the N/A gap is .024, run .028-.030"

Hyper pistons will handle just about anything you throw at them except *severe detonation* and over heating ( lean afr).

I would look into a water injection system for 15psi boost.
Goes a long way to supressing detonation and ensuring reliable power with high boost on pump gas.

Proform makes a nice piston ring filer but you can file them by hand.

The typical stock OEM ring end gap is quite small (.014-.018") this is for a low horsepower motor that doesn;t make much heat ( power).
You eed wider ring and gaps for a hi perf motor that makes a lot more power than stock. This is where most people run into problems with cast pistons. High horsepower = higher heat requireing a wider ring end gap.
With these OEM recomended ring end gaps the top ring gets hotter than usual, locks in the bore at TDC lifting the top ring land. Broken piston, cracked cylinder wall. Ouch

 

Thanks for the info you have been very helpful. I have another 350 block in my shop I think I'm going to buy a engine kit for it and run the turbo on that instead of putting the turbo on my current engine. You know do it right the first time.