Question about compression ratio

[teme]

I'm building turbo engine out of my n/a engine, and really doing a full engine rebuild.
Pistons will be ROSS 8.5:1 , and using my n/a head. So my question is, do I have to modify my cylinder head in any way to get the compression ratio safe ? I'm going to run on hight boost with evo 16g turbo and aiming to 300-350hp.

Friend of mine told, that I would have to modify the head so that the compression ratio wont be too high.

Some expert help would be great.
Thanks !

 

[nickrule99]

You dont need to modify anything.

You *could* get a beefier headgasket, but thats not really needed for a 16g. Maybe a set of ARP head studs, but thats even not really needed- though for $75 its good insurance against blowing your head gasket.

 

[teme]

Ordered already Cometic- Metal Head Gasket, and ARP head studs

 

[nickrule99]

Your going to need to have the block and head planed for a metal one, otherwise it wont "seal" right.

 

[teme]

Great tip thanks.

 

[BlknBlue2G]

Am I wrong in thinking that you need to give the piston manufacturer your cylinder head displacement, stroke and head gasket thickness among other things when you are buying pistons. These can be used to determine what your final static compression ratio will be, not only the piston dish.

 

[teme]

Yeah maybe if tou are buying something else then specific pistons, that are designed to 4g63 block. Like my Ross pistons.

 

[Turbo Talon DL]

Is it bad to not have the oil squirters for the pistons? I know the N/A cars didnt have oil squirters. This wont be a problem for this guy will it?

 

[teme]

Is it bad to not have the oil squirters for the pistons? I know the N/A cars didnt have oil squirters. This wont be a problem for this guy will it?

In europen n/a cars we have oil squirters

 

[nickrule99]

Is it bad to not have the oil squirters for the pistons? I know the N/A cars didnt have oil squirters. This wont be a problem for this guy will it?

Its a matter of whether or not you think you need them. Some will take the squirters out to keep a high oil pressure, others swear they are needed to keep the pistons happy.

 

[The Foos]

I would polish the in-cylinder part of the head...This will stave off detonation, a good thing if you plan to run high boost (20 psi +)...if you are staying until 15 psi, you will probably be fine without it...

Oil squirters aren't a big deal...they are nice, but I wouldn't worry about it if you are using a NA block...

You need to install a knock sensor though...

Scott

 

[teme]

But I do have oil squirters in my n/a block and I have knock sensor in my n/a
European import have small differences