can you use non turbo pistons in a 4g63 turbo motor?

[ssmokeyy]

I have a guys car in my shop and when i got the head off the motor i find these pistons with markings of g63d mark on them with no other marks witch mean there from a 1g non turbo 4g63. Is it safe to run this motor like this? He was told they put in ross pistons but they look like factory pistons to me. The dish is really high almost flat. If this is safe how much whp can they handle?

 

[1990AWD]

You can run non-turbo pistons, but I wouldn't trust them with much more than 10psi of boost on a 14b. The main reason being the piston rings just aren't designed to handle boost like the turbo or aftermarket pistons are.

 

[clipto]

If you want it to blow up you can use them.I really wouldn't if you wanna boost it. If it's stock you will be ok for the most part to keep it as is, but if he tries to make more power he most likley will run into issues.That's all I really got to say.

 

[mj1212]

I wouldn't run anything higher than 8psi just like any other n/a pistons. Higher than that you could have some serious damage depending on if the rods are the same.

 

[ssmokeyy]

thanks guys for getting back to me so fast. Yea this kid has been ####ed over bad hes spent like 20k over 2 years and no shop has done him right. He paid for ross pistons and got these. Just wondering dose ross use g63d on any of there pistons?

 

[clipto]

If no one chimes in take my 2 cents.You can check with ross what pistons those are if your unsure pics are always good to post of his car and what he has so we can see.I personally like ross pistons, but need make sure there right for his car.I would just build the motor right also check what rods are in there too.Cheap would be just replacing the rods with 1g rods and 2g pistons if it looks like they don't turn out to be what you thought they are.That would save him alot of money and worry unless he just wants to build his motor for like 500hp,but stock 4g63 turbo rods and pistons can do fine on stock or up to 400hp I have seen may cars get those numbers with stock bottom end, as long as they are from 4g63 turbo.The 4g63 n/a motor has some differences then the 4g63T(turbo) motor so check on some insite on the forums differences between n/a and turbo 4g63 motors.Hopefully this will send you in the right direction.

 

[kronus]

It's not that the pistons can't handle boost, it's that they can't handle knock. The ring lands are so high up on the piston that if something goes wrong, good bye. So if your tune is perfect, you could try it, though there are much safer options while still maintaining a 9:1 CR.

 

[BogusSVO]

The first hint that they are NOT Ross pistons is G63D that is cast on top in the dish.
Ross forged pistons will be fully machined across the crown of the piston.

From what I have seen, the NA postons will crack the ringlands, This happens due to the tighter ring end gaps, the end gaps will butt together, causing the ring to flex and bust the ring lands.

The butting of the end gaps happen in lean conditions, same as pre-det/knock

 

[H@xtGSX]

Take pictures of everything and give them to the owner as you work. Someone screwed him over really bad and he will likely be mad enough to take that to S.C. court... you do not want to be associated with any of that crap. Cover your hind end and give him some assistance in getting things set straight by taking a lot of pictures documenting everything you find. That's what I would do, having seen what can happen with that kind of stuff from a friend of mine who does auto work.

 

[JusMX141]

Non-turbo on the right, turbo on the left. The ring lands are closer to the crown on the non-turbo piston, so they are much more fragile to boost and/or detonation.

This has been discussed.

http://www.dsmtuners.com/forums/newbie-forum/374737-4g63-non-turbo-pistons-4g63-turbo-block.html

http://www.dsmtuners.com/forums/newbie-forum/374255-non-turbo-pistons.html