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OK so I ran a search and looked here and there, many running a few piston types and brands. Looked through the thread in the quick ref as well. Something that seemed to be missing from many of the threads were a few possible choices and perhaps some info. I am wondering why I don't see many if any Jap brand names being thrown around, is it purely price? So far I have learned Venolia are at least 'buyer beware' and most others are quite good as long as the clearances and ring choice are right. That and the engine builder doesn't do something dumb :D

So how do the Jap brands stack against the more common ones I see here? Is it purely jap brands are too expensive or are there other issues? How many actually manufacture their own or are just reboxed?

JUN

Tomei

HKS

Wiesco

CP

JE

Arias

ACL

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jap brands tend to use the best pick of piston manufacturers and use specific models, ie the trust pistons i use in the top SR's i build use a crown design and special ceramic coated rings only available under license through trust even though the manufacturer makes "other" SR20 pistons.

Arias are a good budget brand and i use them mostly on budget builds but i am not a fan of dished crown in any HOT SR20 i prefer the flater notched crowns, i am currentley building a test engine with SRP (JE). so i will soon know what they are like.

i dont know of any jap manufacturer that manufactures their own pistons but most are made to spec and are not available in another brand or boxes, they are made under license.

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Interesting. Personally I am looking at a Tomei forged piston kit for my RB25DET however I'd have other things to sort (like being able to drive while R33 is off the road) before embarking on a full rebuild.

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you need to look a a few things to determine whether or not you 'need' the extra benefits offerred by these dearer pistons, on many builds i will talk a customer down and prefer they spen money elsewhere for their application but for extreme and high hp and high rpm i prefer the jap brands as they tend to offer a better life cycle and in SR's they offer a unique crow design and ring combo..... oh and zero noise.

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Mostly what people think are a good piston rather than actualy using them but still a bit of info there.

So JUN/Cosworth, HKS, Tomei if you're 'loaded' or chasing big power figures otherswise CP, Arias, Wiseco etc will do the job cheaper. Venolia if you want to brake something.

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ACL and CP pistons are both very good pistons for the pricing... I personally prefer ACL as they have a better ring kit... Piston wise they are both very comparable quality....

I'm personally running ACL pistons and have had no problems

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you say hks and jun pistons if u chase big "power figures" who said u cant make 1000hp with a set of CP's? a set of well made forgies is what you will need. You can get a rebuild kit from racespec for a couple grand..

Edited by LTHLRB
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i can see where he is comming from though. he said some manufacturers have certain technologys which is only available by licence so you will need to go with the jap brands that have this available to get it.

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what has stopped the old boys from making 800hp in a big block v8 n/a?

if you want to have that backing then yeah use jap brands.. but i would only use jap brands if im using a full kit (stroked engine) like full hks, tomeii or nismo.

just talking like this because iv seen ALOT of engines built with arias, acl, cp and wiseco

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nothing is stopping anything. i have ACL pistons in my engine as im not made of money.

I would like to have the jap stuff in my car though.. they build more RB engines then us... well that might change soon though lol

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