Hi,

 

Given that you alter all of the other parameters correctly, injectors, fueling, ecu etc. what do you think the stock pistons can take in PSI?

 

Mark

safe around 14.5 psi or 1 bar;) could go 17 but it is pushing it a little IMHO!

Last time I was at santa pod my car overboosted and peaked at 1.25 bar (around 18-18.5 psi I think).

 

Nothing popped :)

I disagree with 17psi.

 

If the fueling and charge cooling etc are all up to the job then I reckon the stock engine will easily handle 500bhp which is like 20+ odd PSI on bigger turbos!....... but there is one point and this is where people usually foul up - THE TUNING HAS TO BE PERFECT. Poor tuning, poor fuel, crappy plugs, misfires, lean conditions, detonation etc kill engines, not the power. Increased power just adds to the risk and degree of damage.

 

I have read up a great deal on forged pistons blah blah blah. The general consensus is that people don't upgrade to forged pistons to "handle the power". They are installed to help prevent or limit the damage as a result of poor tuning, detonation etc.

 

There is an MR2 (2 ltr turbo) in the states that ran over 500bhp on stock internals without a problem - the tuning was sweet.

 

Sure you will get some premature wear with increased power but there has to be a compromise somewhere.

 

Andy

The mr2 turbo has the 3sgte engine, a massively over engineered engine - apparently. Was made for homologation as a group A engine in the celica gt4, and later used inTom's Castrol Supra.

Thats why the mr2 can run high power, not saying the zx engine cant mind you, and agree with all your points ;)

 

Ill go away now :)

Don't forget there's more than one way to skin a cat, as they say..

 

There are lots of ways of getting big power - you can whack lots of boost through it, and leave it at that, or you can up the boost and change cams, port and polish, bigger throttle bodies etc etc etc, or you can run NOS on top of it all..

 

I've read of Z's running around 750bhp at the crank on a stock bottom end (stock pistons, rods, crank and bearings) - I would imagine they haven't achieved that by simply slapping gigantic turbos on, however, though they're surely going to be well above 20psi.

 

Personally, I'd stick with stock internals, as long as you're planning on doing something other than just putting enormous turbos and injectors on the car to achieve massive power.

 

If you want to run NOS, then I'd definitely think about reworking the bottom end - forged or coated pistons, stronger rods, and stronger (Z31 is a possibility) bearings.

 

If you're going the 'normal' tuning route, then stick with stock pistons unless you are going for huge power.

 

All that is IMHO - never having personally built a 600rwhp Z..

Have run my Z @19psi without any detonation on scramble mode for 5 seconds at a time.

Ask PeterR the same question about stock pistons.

Also who in the UK can can set up a Z32 to perfection?

opinions opinions that's what this place is all about LOL:D

I forgot to mention that was over 500hp at the wheels for the MR2.

 

Like Topless said "Given that you alter all of the other parameters correctly, injectors, fueling, ecu etc". I agree that you can't just bolt on bigger turbos, a couple of boost jets and a Happer Shopper ecu and hope to get away with it.

 

What was interesting was that about 8/10 of the people I have seen on forums who did upgrade the stock internals (particularly forged pistons) did so beacuse A. Its a statement! "Its cool" or B. Other people are doing it. 2/10 really knew their stuff and stated that they wanted extra protection from detonation incase the "tuning fails" plus they were aiming for silly hp anyway.

 

Nissan built the Z engine to handle a lot more power but under tuned it because of power and emission regulations. They over did the brakes though LOL.