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Power Limit of RB26 Rods?

Sneezer

By Sneezer,
in Engines & Forced Induction

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Sneezer Apprentice

Sneezer

Posted
Posted

Does anyone know what the maximum power limit of a standard RB26DET con rod is? At what point do they stretch/bend?

I have been offered a set to put into my RB25DET engine as an upgrade. So I need to know whether it's worth it.

Also you guys talk about Linished rods. Can someone explain what that is please?

Cheers Fellas :P

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https://www.sau.com.au/forums/topic/31078-power-limit-of-rb26-rods/
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R32-GTS Mentor

R32-GTS

Posted
Posted

I am told by relable sources and have seen GTR's make 450rwhp + on standard rb26 rods.

I am currently building a rb26 and not sure yet whether to upgrade the rods or not. I think it would be more for security. And with the forged rod been lighter it should revv a bit more freely as well.

hungry6 Experienced

hungry6

Posted
Posted

I can say from a hands on experience that rb26 and rb25 rods are world apart. they have different shape beam the egdes are different also thicker and the most important of all is that the rb26 rod carry a masive bearing end as comparo to an rb25. As for power capacity is all depends on how well u tuned it. But big numbers have been recorded.

Steve Grand Master

Steve

Posted
Posted

Merli, one place that comes to mind is http://www.skylinesaustralia.com/forums/sh...ead.php?t=28130

Steve-SST, who has played with many RB25s and RB26s, is quite adamant that they are the same in most cases, just some RB25s came out with weaker rods, but it appears from his posts that most had the same rods as RB26.

Merli Grand Master

Merli

Posted
Posted

Very interesting read!

I suppose it's quite possible, as all RB25 failures I've seen from excessive power levels have been piston related, which THEN leads to the rods punching holes through the block.

I'm not so sure about the claim that "but some RB 25s have weaker rods but a lot have GTR rods" though... That just seems very iffy and unlikely to me.

Either they all have the same rods or don't. Or all Series 2 and on have RB26-spec rods, or something like that. The claim of:

The only real way is to pull it down but some RBs respond very well to boost upgrades-Exhausts etc and some don't, the ones that don't tend to be the dog motor as the head flows less.

seems like it's based on not enough evidence to me, and based on one or two RB25s grenading and resulting opinion that it had "weaker rods than the rest" and was a "dog motor"

But I suppose Steve-SST has seen a lot more RB25s than I have, so dunno.gif

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