PT Turbo/SRT4 Pistons in 4G64

[tacoman123]

Hello:
As many of you know, SRT4 pistons are selling for dirt cheap out the dealership (compared to Wiseco or JE pistons).

The bore in the 2.4L 420A is 87.5mm (3.44"), where as the 4G64's bore is 86.5mm (3.4055").

I was wondering if the 4G64 can be bored out 1mm, this will both increase displacement (calculating it, I found it it will increase by .055 liters, or the new displacement will be 2.405L, from the old 2.350L). Although I know its not much of an improvement (displacement wise), but it IS something.

Now, after the 4G64 block is bored, will the SRT4 pistons fit?

Will the work on the 4G64's connecting rods? Will the stock wrist-pins fit, without modifying them?

What else would I have to look out for?

Thanks

~Tacoman

 

[tacoman123]

Bump...

~Tacoman

 

[coltboostin]

1)) What is th echeap price they are selling for?

2) Check the wrist pin diameter of the SRT-4 pin and the 4g64 pins and yo uwill have your answer

3) and in the end, yes it will work

 

[Ben K]

You don't want to use the stock SRT-4/PT turbo pistons. Hyperutectic pistons don't like heat and detonation that turbo engines produce.

 

[tacoman123]

Originally posted by Ben K
You don't want to use the stock SRT-4/PT turbo pistons. Hyperutectic pistons don't like heat and detonation that turbo engines produce.

That is a good point. But some people supposedly went to 22 psi on the stock internals. I'm just planning to do 20 psi, not more.

P.S. I'm using a Big-16G.. not the one from the SRT-4 though.

~Tacoman

 

[98TsiAWD]

Check out this thread, someone in it actually used SRT4 pistons in a 4g64.

http://www.dsmtuners.com/forums/showthread.php?s=&threadid=49472

 

[DSSA]

All I'm seeing is some guy claiming that he's doing a "buildup" with the PT pistons. I don't see him stating that the car is even running, much less, well.

Piston diameter, and pin sizing being the same are nowhere *near* being the only factors determining if a piston will work in a motor.

Deck height? Pin height? Pin offset? Deck design?

Will the quench and dwell be correct?

Sounds like over-simplification to me.

 

[NosLaser]

tacoman,

I think the point Ben was making is rather obvious. Yes, you can get away with running hyperutectic pistons (they came in factory turbocharged vehicles such as the Typhoon/Syclone) but they don't leave you any margin for error. It's like cranking the boost on a stock rotary motor. They will take it so long as they don't detonate, but do it once, and you could be looking at serious damage. The idea here is 'is it really worth the risk just to run another manufacturer's stock piston?'

Regards,

 

[coltboostin]

yes yes, I see. Is ti worth it though? How much would the savings be over say a ross piston or somthing similar?

 

[rdrkt]

Originally posted by coltboostin
yes yes, I see. Is ti worth it though? How much would the savings be over say a ross piston or somthing similar?

I think you would "save" 200 bucks max over a set of Weiscos. I agree with DSSA I would be shocked if the valve reliefs matched up.

 

[coltboostin]

yeah that is why I asked, it would be no where near worth it.

 

[greyforestgst]

bore isnt the only thing that needs to match up
it has to be near the same weight to still be balanced, the correct height to give a good 8.6 - 9.2 cr, have the same wrist pin size, not have any play with the connecting rod between it and the skirt...etc

im amazed someone got it to work. just buy the forged anyway; they're built for the car.

 

[HybridAWD]

not sure if that statement about this guy using PT pistons was refering to me. So on that note, i used Pt pistons, had tuning issue because i went from stock to radical and a lot of things were flipping out and i just needed the car running.... so now the car is being broke in somewhat of a "stock" manner and will be soon getting my T4 back on it with full exahust tuned DSMlink, 880cc injectors.....

a buddy of mine dyno'd his stock 2.4L with the same exact setup as me and put like 246awhp down at 7-8psi i think

http://hybridawd.vadsm.com

there is the motor with pictures