supracharger19

I own a civic d16z6 vetch turbo. I lately I have opened it up because it had low compression and a coolant problem.

Right now I'm into low end torque and I was wondering if it is ok to run domed pistons with a compression of 11:1 to 12:1 while boosting 3 to 5 psi? Would I need forged rods and pistons or am I able to get away with just the pistions?
Also, what are the underdog companies for pistons.
Thanx for your help,
A.

h22a4_sol

u can run 6 7 psi and be safe on a stock motor so 3-5 psi isnt **** but if your getting pistons get eagle rods

Ruben19

not point of boosting that low.
swap the pistons

h22a4_sol

yea swap pistons and get it sleeved and put some injectors and go ATLEAST 12lbs

dapek

x2

Do you even know why he would get it sleeved? And psi is relevant to what turbo he's running, so saying at least 12 psi is stupid.

h22a4_sol

yes i do know y he would get it sleeve. sleeving isnt just for block durability for high boost applications it also increases displacement with a bigger bore. so for you to say that saying atleast 12psi is stupid its really not if you actually knew what sleeving is for. let me say it again incase you didnt comprehend the first time. sleeving a block isnt just for durability on high boost applications it also increases displacement with a bigger bore.

supracharger19

I want to have high compression pistions and boost 3-5 psi. I just wondering if that is ok on the motor. I'm pretty sure it is better not to sleeve the block if you don't have too. On a stock civic you should only boost a max of 8 psi, I think 12psi would blow the motor.
A.

apexi_rsx

not gonna be too feasible to run 12psi on pump gas with that kind of compression. higher compression is gonna be more prone to detonation or engine knock. you have more room for error with igntion with lower compression. better get this thing tuned rite away if u go this route. id run sum where near 10:1 compression like the b16 has.

CivicSpoon

dapek is right, PSI doesn't mean s***. 12psi with a T25 is not the same as 12psi with a GT35R. It's all about how much power your parts can handle (generally speaking).

With that being said, 3-5psi with any turbo is going to be worthless. 12:1 compression alone is right near the limit for pump gas. Stock rods are good to about an average of 200-220hp (I've seen quite a few people claim up to even 250-ish hp), so yes you're going to need rods, if you plan to go over that "limit". I hope you also have good engine management and you're planning on getting your car tuned after whatever you decide to do.

apexi_rsx

tru cuz a greddy t25 turbo @ 14psi barely brings a stock motor up to 200hp vs a gt28r on 10psi making about 200-220. anywhere over 350hp is gonna be hard to obtain on pump gas. you DO NOT want to run a gt35r on a D series without alot of headwork and a big cam.

Kidnkorner

14.7 psi only increases rod load by 20%

So long as it's tuned and you can eliminate detonation and preignition 100% there isn;t really an upper limit. It's just gets really difficult to to tune out these conditions with higher boost. rods, pistons and sleeves don't eliminate these conditions, just stand up better to them.

You could get a water mist injection kit and fill it every 3 days with distilled water, this a good way to help that out. I know of someone who did a water mist injection and tuned his NA K20 to run on 87. Not only does he get a little more power than if he was running premium but he reduced his fuel cost and increased his fuel economy. I'm talking about 100% distilled water, not a 50/50 mix of meth.