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Hi guys my 32 Gtr has a excedy twin plate carbon clutch that is showing signs of slipping above 350 kw after 3 months if other issues being tuned. I spoke to jb as I need a clutch to hold 450 kw and 1000 nm of torque, jb is $1295 then I read about npc clutches but havnt spoken to them yet, is jb worth the apparent extra coin?

Scott

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I think the biggest NPC single is rated at around 400kws...after that you would need their twin plate that is about 1400$ iirc...there is a lot of debate over which is better single or twin...personally I would go for a twin or even hunt around for a triple for that sort of power as it supplies a better/softer transition...The brute force of a single while effective at getting power down, that load can be tough on your driveline and your crank bearings...Thats my theory anyway I'm sure many will disagree...

That kinda why I went the twin but probably should have gone triple in the first place, oh well ... Live and learn but I don't want to take this thing apart again after this so a few hundred wont kill me it's better than 3k for a jap unit I guess

Nismo copper mix twin plate all the way, drives like a factory clutch and know of one holding 475 at the wheels, including massive launches and been in the car for 8 years

Also have the added bonus of not exploding

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Decided to go Jim berry solid centre single plate, I rang npc and wasn't really impressed with their knowledge. Jim explained all the different clutches and that single twin or triple plate the only thing that stops stuff breaking is mechanical sympathy. As you strengthen one link something else becomes weaker in the chain. Also he uses new components unless you send him your clutch that is . Price wise it's $1400 delivered whereas npc twin plate is $2500 same as nismo. Interestingly jim says nismo is the same clutch as excedy twin plate and has good clutch plates but the pressure plate is rubbish in his opinion . He also says its impossible to rate a clutch for horsepower or torque as he explained how do they do it? Rate it at 400kw what does that mean 402 it fails ? AnywAy just thought is share part of my long convo lol

He can talk the leg of a chair that's for sure...NPC you probably just got a salesman, where as Jim always answers the phone personally it seems...Ask to speak to the owner at NPC im sure you will get a wealth of knowledge as I believe he did his apprenticeship at exedy.. ;)

As for rating a clutch I think it is fair to give a basic guideline if how much it can handle..So no it doesn't mean it will fail at 402kws..and saying such a thing is a little ridiculous on Jims behalf...It is merely an estimate or a guideline as to how much it can reasonably handle....NPCs 300kw clutches have been known to hold 350kw...but they give 300kws as a reasonable estimate of what it can handle and build a clutch that exceeds its own specifications..I think thats fair..

Didn't know the twin plate was 2500$ though..So JB is probably your best bet on that budget anyway..hope it works well for you ...

Yes possibly got a sales man but he was very disinterested and only wanted to sell me a single plate anyway had to push for twin price and yeah it suprised me a bit too as its same price as jap units! I know what your saying about a guide but the way he explained it in much much much more depth kinda made sense. He said maybe the japs and other countries could have a way of testing it but in oz there was only one machine who I can't remember and they don't let anyone else have access to it. Also he said the two best manufactures Sachs and ap have exactly the same clutch but the ap is rated at 40 percent more than Sachs and Germans are generally conservative but that does seen like a huge difference so should only be thought of as a rough guide. He said he has had his full Monty on 1000hp rb and 2j but he won't rate it at that as it depends on many other factors such as use, driver car weight but mainly the nut behind the wheel , however I see what ur saying and I also hope it works in my application

In fairness I agree with Jim if you side step a Gtr say with semi slicks that don't break traction something has to give and if the clutch is upgraded then its further Down the driveline, seems logical. I do my starts as he suggested anyhow ride it a bit in first , short shift then get into it, possibly could be faster but at least I can drive home

Oh for sure.... and if you have 4200lb of pressure plate whats gunna give first ?

At the end of the day its cheaper and easier to replace a clutch than rebuild an engine with shot bearings ;)

but yes, driving style is the ultimate decider no matter what clutch you have....

But once it's clamped or engaged does it really matter if its 3000 or 4000 lb? Surely it's only relevant if clutch is dumped ? Please explain your thoughts / experience before I make another mistake

Ta

nah you're not making a mistake mate....good clutches...:thumbsup:

I was going to get a JB but scored an NPC for half price and its an great clutch...and I know there is more than a few racers here using them ...I don't know why SIR_RB is knocking them, unless he was knocking the sales service and not the clutch themselves......

There are going to be lots of different experiences. Here is mine..

Got JB 4200lb clamp single, lasted 500km, exploded and took out gearbox.. He sent me another and ever time I'd try and launch (slip clutch a bit ) it would weld itself together, took it out after only 5000km and it was shagged, both of them engaged like a sledgehammer.

My next clutch will be a nismo copper mix, everyone with one loves them..

Anyway good luck with what ever you choose

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