Pistons?

Hi, I am currently in the middle of the rebuild on my g63b and was wondering if anybody knew of a forged piston that will work in our engines? And what the compression height of a stock piston is?

Thanks!

If your going to replace pistons and rings , head and all just get a crate motor It will save you time and headaches. I went .20 over pistons .

I work in a machine shop so labor in machining is free I just gotta do it.

ewwww, can the forum start placing orders for machine work. :grin:

You might try Wiseco, HKS, Mahle for some pistons, though the cost will be quite high and you would need the wrist pin and rod and probably racing bearings as a kit to match everything up.

Attachment 15791

why "forged" pistons..... what you got planned for the motor ?

Maybe he going to break a national speed record. We do have one of them speed holders here in the forum, but he only shows up rarely now.

The g63b is a carbed version of a 4g63, look up forged pistons for the 4g63!

All I've seen is stuff with valve reliefs for 4 valve engines.

I don't think you're going to find forged pistons for an NA 4G63 SOHC engine. And damn, these things are not cheap... half a grand upwards. :shakehead:

http://shop.rpw.com.au/online-store/...bo-detail.html

lolololol $1500 + tax... for pistons? They are made from adamantium right? :lmao:

HAHAH yeah, hopefully. Hey he asked and i showed him. I honestly didnt look for the price before, thats ridiculous!

At least their dual valve springs are reasonable http://shop.rpw.com.au/online-store/...59-detail.html

Pistons are on order, maybe thats why the price is outrageous?!?!?!

$1500 ??? maybe the mechanic comes with them and installs them for you too.:rolleyes:

...and those pistons are still for a turbo application :rolleyes:

you can use the dohc pistons in a sohc it will lower the compression ratio a lot.

Rahtid, the DOHC pistons will still clear the valves in the SOHC? And how much compression loss are we talking? I'd like to build a high compression engine around 10:1 or maybe higher I'm just stuck on finding a forged piston because cast pistons cant handle the high rpm I'd like to run.

Your CR is going to drop to 9:1 or lower depending on the piston type. To be honest I think you're chasing your tail by not going twin cam. You'll get over some hurdles but run into others - you'll be able to get the right pistons, you will easily be able to achieve a CR of greater than 10:1 and the twin cam head will be a major improvement in HP and torque. You'll need to figure out the exhaust manifold and decide how to tackle the intake side of the engine but this is all stuff that has been done before.

lotsa sohc 2.0L starions run dohc pistons. Thicker stronger ring lands.
Several claim the sohc has ~0.5 lower compression than the same piston in the dohc
Some had to cut valve reliefs because of their cam lift.... and that's lower compression turbo motors
So you're going into no man's land with that route

Where will you get 'proven' sohc performance cams ?
And when since cast pistons "can't handle high rpms" ?


I'd go twin cam too
When you're done spending/building that na sohc, $200 worth of dohc junkyard shopping would most likely blow it away
May be worth a look

Doesn't $50 dohc junkyard head give you high compression when bolted onto a stock 2.4 block ?
Could be another route
Or just go nutz; http://forums.austarion.com/viewtopic.php?f=3&t=16193

BradMph has used a Shneider custom ground cam in his 4G63 and he seems real happy with it. As for pistons, well there are 'pistons', and there are pistons. Forged may be massive overkill for a SOHC. Just don't buy cheap ass parts or anything from a supplier that has earned a reputation for having quality control issues. Some brands seem to churn out junk pistons and bearings all the time... Going all forged for internals will make for one tough engine though :grin:

Hey brad, I check in just about every day....:-) I just don't say much...
here are the specs of my turbo pistons.

They are from Nick Arias III, Yes, that Arias.

Attachment 15944

The one on the left is a 14:1 Normally aspirated, the one on the right is the 10:1 Turbo piston from the job card

Attachment 15945

Top with valve reliefs

Attachment 15946

what rpms are you looking to run? the hyundai g4js piston should be a decent compression ratio, and since you work in a machine shop you can work on the head raisng the compression even more,here is a link to the hyundai piston http://www.ebay.com/itm/NEW-PISTON-K...tVtNX7&vxp=mtr

Okay so looking at a DOHC head gasket from the same company they are a different gasket with different holes. Does anybody know a DOHC cam head that is a direct fit? Or what it will take to get one to work on the stock block from the Ram 50?

Thanks