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Old 09-30-2012, 07:42 PM   #1
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Default OEM replacement pistons - hypereutetic vs cast?

is it worth it to pick up a set of replacement pistons, say by ITM or some other manufacturer? I've heard that the oem pistons are stronger than cast ones, which I assume is how the replacement ones would be made.

background- I've got the block totally apart right now, and am deciding how to proceed. I plan on going with some ebay forged rods and either reusing my oem pistons (they appear to be decent) or getting some replacement 1.6 323 gtx pistons for the lower CR.

Any ideas? I don't plan on going over around 200 whp. I know the stock internals should be fine for that, but since everything is already apart, I'd kick myself down the line if I didn't replace SOMETHING right now.
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Old 09-30-2012, 07:51 PM   #2
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If you're not going with forged, then just stick to OEM.
You REALLY gotta be honest with yourself about that 200whp, since 99% of the people want more almost immediately, and it'd be a shame not to go forged now
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Old 09-30-2012, 07:54 PM   #3
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250whp is the happy place for these cars.

I had zero regrets about my low comp forged guts from the turbo engine.
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Old 09-30-2012, 07:57 PM   #4
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You can make all sorts of power on a cast piston if there is no detonation.
The strength of a forged piston does 2 things, it gives you a little more forgiveness during detonation before it melts/breaks, and it will be able to take higher side load and piston speed before breaking. This is more about revs than power.

The GTX pistons look very stout.
If they dont suffer from some hidden defect they should be capable of much more than the small amount of power most people are making.
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Old 09-30-2012, 09:20 PM   #5
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Given that this is the first car I'll be tuning on my own, i also wanted the lower comp pistons to stave off any effects of detonation, in case I don't catch it in time.

I want to stick with around 200 for now due to the fact that I've heard the 5 speed starts getting unreliable around 250, as well as having to worry about other things such as radiator and oil cooler.

I read somewhere (can't remember where off the top of my head) that in terms of internals, the first thing to go are the rings and pistons, followed by the rods. Is there any truth to this?
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Old 09-30-2012, 09:23 PM   #6
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No. You need to start reading the 1000000 threads on that subject and stop asking stupid ******* questions before we gangbang you

If you're clueless enough to not know what goes 1st in ours motors, then you have wasted every single one of the 4 years you've been on this site.

We are all disappointed.
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Old 10-01-2012, 03:17 AM   #7
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holy crap i've been on this site for 4 years... i too... am disappointed.

That being said, I know the consensus is that rods go before anything else, but I was also curious if anyone has had pistons or rings go bad before the rods.

The cheap ebay pistons seem to list the 323 gtx, even the turbo, pistons as being 9.3:1 CR. Haven't seen any of the 7.8:1 ones yet. I'll probably end up staying with my old oem pistons, just clean them out and balance them with the rods as best I can.
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Old 10-01-2012, 09:12 AM   #8
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You can definitely melt pistons with bad tuning....You can melt just about anything actually
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Old 10-01-2012, 05:38 PM   #9
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True. I'll run safe timing and increase it slowly. Half the reason I'm doing this is for the learning experience anyways- it's been quite educational already.
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Old 10-02-2012, 04:37 PM   #10
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Bonus question: is it ok for me to reuse my current wrist pins? I picked up a set of ebay rods and will probably stick to my current pistons, as long as everything specs out.
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Old 10-02-2012, 04:54 PM   #11
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Quote:
Originally Posted by crono36 View Post
The cheap ebay pistons seem to list the 323 gtx, even the turbo, pistons as being 9.3:1 CR. Haven't seen any of the 7.8:1 ones yet. I'll probably end up staying with my old oem pistons, just clean them out and balance them with the rods as best I can.
You will not find those 7.8:1 GTX pistons. I know that neogenesis2004 looked forever and I think he might have gotten the last new set that existed on earth. He ended up blowing the ringlands in that motor.

I just asked, neogenesis2004 and he said he got his ones from corksport. So I would suggest trying there if you are serious about finding some.
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Old 10-02-2012, 05:24 PM   #12
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i'm curently using BNIB oem canadian edition gtx piston/rods(known here as a familia b6t)7.8:1 comp.

they were available at the dealer,cant say for sure that there are some lefts.

new it gave me a 155-160 psi comp each on a compression test.
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Old 10-02-2012, 08:30 PM   #13
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hm... how much did you end up paying for the oem ones?

I'm impressed that neongenesis blew out ring lands at 7.8:1.
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Old 10-02-2012, 08:33 PM   #14
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Quote:
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hm... how much did you end up paying for the oem ones?

I'm impressed that neongenesis blew out ring lands at 7.8:1.
Well we think that is what blew, we never actually pulled apart the motor to check. He sold it to a friend for cheap, and then I never heard what happened to it after that.
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Old 10-02-2012, 08:55 PM   #15
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Quote:
Originally Posted by crono36 View Post
hm... how much did you end up paying for the oem ones?

I'm impressed that neongenesis blew out ring lands at 7.8:1.
Bought the engine freshly built by original owner, who swinged his track car in a wall attempting a dorifto maneuver .can't tell you the price of the parts since i didin' t keep the papers ... The guy worked at the dealership so he got them for ''cheap''
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