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How would this go? on a 30de, with the pipe's coming into the chamber bell mouthed.

As i could then run run the intake straight to where the battery normally goes.

Appart from improving response, would this improve top end at all, or anywhere else in the rev range?

and on that note, longer or shorter inlet runners better for power?

ta

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There's an R33 out here with that setup on it.

N/A, RB30 block, 2.5 head, front facing plenium and custom 90mm throttle body, he made himself. (aviation engineer)

The car ran 140rwkw I beleive, with plenty left in the tune. He never really bothered chasing any more power out of it, had plenty more potential tho.

Seemed to have plenty of torque and didn't lack top end either. Can't quite remember 1/4 mile times tho.

The only thing I'd worry about is that you may not have enough pressure for all cylinders to get even distribution of air. I might be wrong, but it is my understanding that this is good in theory, but in practice the cylinders at the back lean out.

longer runners the better, there is plenty of books on the subject at your local library - the whole thing is a bit of a science, ergo' do the reaserch and it will come up trumps, dont and you will lean out the rear, rich on the front and your engine will go pop

If your guna mod the 25 inlet at least do something like in the pic attatched.

Making a front facing plenum for an NA motor isnt that easy to do, lots of R&D is needed.

I would love to do that, but funds for that initial setup, plus full after market management for map sensors = $$$++

I did look up the plenum volume, and from what im reading it seems that longer is more for low end, and shorter is better for high end

i'll sleep on it, but im thinking prob best to just keep my twin TB setup, and internally polish+port match the stock plenum and runners

but on that note, something else got me thinking

I also noted about variable length inlet runners, a few manufacturers do this now days, would be interested to investigate possibility's.

for example, has anyone seen the rb20 redtop plenum? it has normal length runners and short length ones, interested how effective this was, and why they dropped it.

If your guna mod the 25 inlet at least do something like in the pic attatched.

Making a front facing plenom for an NA motor isnt that easy to do, lots of R&D is needed.

who's motor is that? I would liek some details plueaaaaaaaaaaaaaaaaaasee!!!

been dying to hear a non turbo RB with trumpets!

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