I have a fully build b16 head with super tech goodies and a blown gsr block I'm planning on boosting it after a stock rebuild my question is if I do need over sized pistons is there something that would give me a better compresión ratio than the gsr pistons? My goal was 300 hp on stock block with ARP but would like to be able to turn up the boost to 400?

 

What compresión would LS pistons give me on this setup? Better? Some kind of thicker head gasket ?

 

Looks like some one needs to to research what they want

Get the block checked at a machine and see what they say about the block

Ls pistons in a gsr block? Never heard of that, I wonder why Honda didn't think of that? They could have saved money by communizing pistons between motors

 

Anybody?

 

Yes you'll most likely need to go with oversized pistons. If your dead set on using an Oem piston Id recommend just staying with the gsr pistons. 300hp is no problem on a stock block, 400hp is pushing it, your going to need to have a good tuner. If you really plan on pushing 400hp+ it would be smart to just get a forged piston and rod combo to start with instead of spending the money on an Oem rebuild.

 

A b16 piston will net you a slightly higher c/r.

 

Pretty sure he is asking what oem piston he could use to lower the compression...

op, a stock gsr w/ a b16 head using the gsr pistons is 9.8:1, ls pistons is 9.34:1, b16 is 11.06:1(pr3) & 11.27:1(p30) <-----that is not slightly higher.

 

Yes I think lower compresion would be better.to get closer to the 400 plus mark I'm looking for the most inexpensive piston for optimum c/r

 

What's optimum compresion ratio for boost ? 9.8 or 9.3? That's my question

 

Wikipedia; B-Series will tell you the compression ratio of every B-Series engine.
And if you're only aiming fro 300whp you can do it on stock LS internals fairly easily, but considering you're going to replace pistons anyways might aswell get better pistons with abetter compression ratio.

Why don't you search 'compression ratio for boost' or something along the lines? Hundreds have people have boosted these cars.

Lower compression means you can boost more; Higher compression means can't boost as much... Basically.

Do some research and stop asking questions without trying.

From what I read if you stay below 10:1 c/r you're playing it on the safer side. The lower you go the less risk of detonation...Regardless;

RESEARCH

 

since ur block is blown mine as well get the good stuff since you alrready have to replace it. You will prob want more power down the road and your motor will be ready.

keeping 10:1 compression is fine. Thats what my setup will be.

 

How much can 9.8 compresion handle 400 hp?

 

anyone who says you need low compression for boost just has a poor tuner... more compression is always good... if you feel like dropping it i wouldnt go lower than 9.8 then again if i was pulling the motor apart i wouldn't bother with a crappy oem piston

 

you'll need forged pistons and rods for 400... stock internals won't handle that at all.

 

Can some one confirm I need forged Pistons and rods to get close to the 400 hp Mark?

 

Reliably yes...

 

or you know, just ignore the people that post and have done this before....

 

It sounds like he needs to take the car to a shop to me... If you're asking questions like that, then you've got no chance....

 

I did a little research a stock turbo 1.8 Volkswagen motor has 9.5 to 1 c/r

 

 

I have no problem getting a great tune I could even take my car to bisimotos shop in chino if I really wanted to he charges the same as any other shop $300 its just farther do it dyno is down the street from my house. I would just like to have as much horse power as posible without going forged since its so expensive or maybe just forged Pistons if the price is right.

 

 

It sound's like you've got a HELL of a lot to learn.

 

Yes I know I have a lot to learn that's why I'm here asking dum questions lol I'm trying to roughly map out my build so I don't do anything dum and blow it . So ill be sticking with the 9.8 c/r my next question would be how far can i push that max psi and hp staying save non forged with a great tune? Thanks for the help I'm a boost noob I had a Ek before with a ls and gsr tranny I thaught it was fast and fun now I have a dc2 shell