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Discussion Starter #1
are forged pistons stronger than OEM units? or is it more of a lightweight/easier rev thing? If there's no particular strength difference between cast OEM and aftermarket forged, then I'm all for sticking with original units.

What about piston rings? Are they all the same, or are there uprated units available? What would be the best damn piston rings money can buy?

<sigh>:confused:
 

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Forged pistons can be even heavier than ste stock ones cause there is more metal forged in the same volume. So weight isn't a realy important factor.

The forging process does improve the material properties of the forged metal, also ther are other elements added or reduced for the required strength, heat conductivity, expansion, and wear resistance.

And uprating the pistons doen's cure the cause that killed the previous pistons. Forged pistons die of detonation too, they are harder to kill but will die.. I would make sure that the cause is cured before uprating the pistons.

I guess wiseco pistons will dofine for your job, and they are affordable too..
But there's more than enough choise..

Good luck with the rebuild.
 

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One thing first:

There is no bulletproof piston on the market

It all depends on how you care about the parts,how the block is machined,how you use the car and most important how it is mapped.
 

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I'm glad you posted that, Evo IV, as I was hesitating to say anything! I know that OS Giken make pretty good forged pistons, but nothing is indestructible, and I recently overheard one of their staff saying that they don't like people using their parts irresponsibly.
 

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Discussion Starter #5
with HKS pistons, are the nickel-plating on their pistons really worth an extra 50,000yen?
 

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with HKS pistons, are the nickel-plating on their pistons really worth an extra 50,000yen?
I think your problem is,you dont know anything about engines and especially the RB26DETT,you are for sure living in a difficult country,but if you cant do it yourself,you need to find somebody that can do it for you,so you need to find a good tuner that knows his stuff. You will kill the next "bulletproof" engine in 2 month when boosting to 2 bar on a some unknown turbos,stock fuelpump and 700cc injectors,this cant work,everybody told you,but no,you are the problem,you must realize that there are limits,and when you go over these limits,it cant work.

Sorry for that,but thats what i think,maybe think about that some days. You will spend so much money on a old 32GTR that ever breaks down:GrowUp:
 

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Discussion Starter #7
whatever. I'm just asking about pistons. I learn more and more with every post and every question that gets thoughtfully and graciously answered by knowledgable members of this board, and I'm getting closer to where I want to be. JDM cars are not well supported in Korea - only German cars have significant aftermarket support. So I think you know where you can stick your arrogance, and it's not in anyplace shiny I can tell you that.
 

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So I think you know where you can stick your arrogance, and it's not in anyplace shiny I can tell you that.

Im not arrogance,in no way,im not telling you that you should put anything in your a**,i mean you can do it when you want,no problem,its yours.Maybe its my bad english that doesn´t allow me to find the 100% right words,my german is much better but im sure du würdest nichts verstehen,wenn ich Deutsch mit dir rede,mein Freund,i just want to point you in the right direction,it is not the piston that failed,it is not the fuelpump that failed,it is bad mapping,to hard use and not knowing what a engine needs,build a good engine,map it 100% and try to keep on the safe side,only push it when everything is 100% and dont try to do stupid things with it,you will have much fun,if not,we will speak here in some month again,when you are searching some "bulletproof idontknowwhat".

Alex
 

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Discussion Starter #9 (Edited)
ok, that was a little harsh, I'm sorry EvoVI. You are entitled to your opinion.

There are always those in the tuning world who will push things to the limit. Maybe I took things too far, but it can't definitively be said, as I didn't blow a thing with my 2 second 2 bar test. If anything, the 15 year old stock fuel pump probably wore out from the Sard 700cc injectors. Thanks for helping me make that link.

Blowing an engine is by far not the end of the world, or something to cry about - I certainly am not. It's a chance to start fresh and try to get things better. As I think I mentioned, my long block was FREE (cost nothing), so there wasn't a whole lot I could do about that. But now, I can exactly spec the internals, and guess what? I'm trying to gather enough information so that it gets done right.
 

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Discussion Starter #10
you have a point EvoVI, sometimes bitter pills are hard to swallow for the one who needs medicine...
 

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Even though Evolution was a bit harsh ,it's pretty spot on ,your just going to blow up your engine again .Uprated pistons might just last abit longer before it goes t1ts up,you need a decent set up by someone that knows what they are doing .
 

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Discussion Starter #12
well, what's the weak link that everyone seems to see except me (and I'm NOT talking about setting the boost at 2 bar!)? Half the stuff under my hood is two months old and my map was, well, I could only measure wideband AFR and knock when I mapped it. I was blind to EGT and losing the fuel pump was bad luck and a bad choice.

perhaps my post title is most misleading - I don't for a second think that there are magic pistons that will never blow - I composed the title more out of whimsy than seriousness. And very simply, all I was really wondering was:

are forged pistons better than OEM, and in what ways?

And there are answers here, but not anything definitive - see "conspiracy theory" thread :p

and finally, anyone know anything about the HKS nickel piston coating that adds 50,000yen to the price of a set??
 

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If you allow severe detonation to happen, then even pistons made out of unobtainium won't help you.
Same as 'uprated' gaskets.
Don't try to mask problems, just design so that they don't happen in the first place. (...still shivering from the '2 bar' thread...:eek: )
 

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Discussion Starter #14 (Edited)
that's the thing - the det had to have come from the fuel pump dying. Of course detonation is the problem and what directly killed the engine. My map had peak knocks at 27-28, but I'll be retarding 3/4ths of the map for certain once my car's rebuilt. Then finally, some serious mapping watching wideband AFR, EGT, fuel pressure, oil pressure, and knock, with a Datalogit and no 2 bar boost!
 
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You piston damage was done by the 2 bar run I am afraid, the STD cast pistons will have suffered from Piston land over load., causing the piston land to collapse so breaking the rings.

A good quality forged pistons will last longer due to it ability to take more load, but even a forged piston will DET if you car has a bad tune or something breaks in the engine i.e fuel pump crank angle sensor.
 

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Discussion Starter #16
You piston damage was done by the 2 bar run I am afraid, the STD cast pistons will have suffered from Piston land over load., causing the piston land to collapse so breaking the rings.

A good quality forged pistons will last longer due to it ability to take more load, but even a forged piston will DET if you car has a bad tune or something breaks in the engine i.e fuel pump crank angle sensor.

no kidding. well, I knew I'd be paying for that folly one way or another. :chairshot

It has been a couple weeks though since that dastardly run (as short as it was), and I'd been able to push the car quite hard in the interim. Well, probably like many things, a combination of things did me in - weakened piston lands from 2 bars, then some hard running, and then a failing fuel pump delivering the killer blow.

so forged pistons will be able to take 2 bar of boost (mapped not to detonate)? I just got a call a few minutes ago, where the shop is saying the pistons look fine it's just the rings that need replacing. But would you advise changing the pistons, based on the premise that, even if the ring lands look ok, that they should be at a minimum be assumed to be weakened and soon to be out the door?
 

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Discussion Starter #17
>>>so forged pistons will be able to take 2 bar of boost (mapped not to detonate)?

scratch that question, from the "conspiracy theory" thread that's just opening a can of worms...
 

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Yes, they will take 2 bar boost, if mapped correctly, there for the engine will product alot more power, but then something else will go bang.

Your best option is to sit down and work out what HP/torque/response you would like to have, then speak to someone/post on here what your plans are, so we can try and help you.

Personally I would be thinking power to weight, far more important, think about how you can make it lighter (target weight)less stress on the engine and transmission, it will last longer too.

Why is your goal 2bar?
 
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but wait a minute 2 bar with std turbo,s is diifferent than 2 bar with a pair of 3540,s. So you need to decide what sort of useage the motor going to have.

We can supply forged pistons to our design for £550-00 for 6 including rings in 86.5mm or 87mm.
 

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a minute 2 bar with std turbo,s is different than 2 bar with a pair of 3540,s.

Yes,2 bar on standard turbos is a lot of hot air and 2 bar on 3540´s is a lot of fun:chuckle:
 
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