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hey guys,tried lookin up info for 20's but not much came up,all 25 and 26 stuff.anyway. im wanting to know if anyone has seen the results good/bad from modifying the throttle position of a standard plenum to a forward facing one.i know its not designed to have intake on side but wondering if any side affects have been found (leans out cylinders etc.) and if cost worthy of modification.

or if anyone knows of a place to buy a good aftermarket one for 20's that would also be helpfull.

thanks.

Edited by orb4me
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Pretty sure there is a guy selling a RB26 one modded to fit an RB20.

IMO they look better than any after market job available.

EIther way though, Nissan engineers did a good job with whats on there. Unless your pushing over 300rwkw there is no need to change it.

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I actually read about RB26 plenums on RB20s a while ago now, but its still applicable.

Dyno tests where done prior to removing the standard RB20 plenum, and it was replaced with an RB26 plenum.

After the plenum install it was re-dynoed and the car actually made less power/torque and was less responsive. Did anyone else read this article? I think it was in HPI magazine.

There is nothing wrong with the stock RB20 plenum I have to say, but I can see where your coming from if your issue is the fact that the piping has to run over the engine. I find that annoying when you want to change spart plugs, but thats about it.

If thats the issue then I dont think its worth the trouble to make it/or get a front facing plenum.

If your issue is the length of the piping, then dont even bother. The way its setup is fine, and dont think you will get much better results with shorter piping.

Just my thoughts..

Edited by abu
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ive seen modded rb20 eccs plenums like you described. i think there is a guy selling them on VL turbo forum. my two cents is they look shit. just save and get somthing designed to flow from the side and not lean out cylenders.

His names LEIGH (DUZ360).

I think there around $600 delivered. He is also on SAU I'm pretty sure.

Yep, stock looks fine I reckon, a lot of after market stuff looks shit.

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first question is why do you want to do it?

just to remove an extra 50cm of piping?

reason y is cause its in a 180sx,i got after market bonnet which i don't wanna chop into as its ADR compliant and crap all room to keep it as a crossover design and they do look better facing forward... thanks for all the feed back.i thort they would lean out. i have read the same article on the 26 manifold,main reason for power diff and torque is due to the runner length,id like to get one that bolts onto and uses bottom half of standard manifold to avoid that.trouble is finding one,id pay good money for good stuff, just going through the options, ill check out links given so hope they will help. thank you all.

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