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I currently have an R33 RB25DET running poncams, GT3540, and supporting mods.

I was recently told that if i were to swap out my 3540r .82 for a 3076r .63 i would still make around 400rwhp with more response and less lag. This was appealing to me as i have just began taking it out on the track and can always do with a tad more response.

Please help out a novice racer by confirming or rebutting this opinion.

Thanks

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If your still running the stock manifold there is absolutely ZERO to gain by going the GT3540. On the same dyno my own car and a mates basically identical apart from one having the gt35 the other the gt30. Both made near identical power on the same boost.

I've since dropped cams in which has pushed power up to 302rwkw on 17psi with the GT3076r .82 IW.

The .63 I doubt on 98ron pump fuel will push 400rwhp 'easily'. You really need the .82. regardless it will still be a lot more responsive than the gt35 .82. Especially in the lower gears and corner exit etc.

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th 0.82 housing works pretty well on RB25's with progressive delivery from what i have seen.

the 0.63 may provide a more light switch power delivery but will probably run out of puff with a 500hp compressor bolted to it.

i was just agreeing with cubes hence the short post.

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its far more balanced and suited to the 25, so yeah.

My 600hp GT30 was quite nice with delivery (.82) all things considered on my 25 back in the day and the 3076 would be more linear again being the smaller comp wheel etc :P Will buzz up nicely is my prediction

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