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Hey people. Just a quick question as i've got an rb25det conversion from a sII r33 into my 180sx. :) Just want to know what to do with my intercooler plumbing. As i used to have a ca18det powered 180, i have the intercooler core and bottom arms of the plumbing coming up through the battery hole and the pod filter area on the left and right.

The thing is, im wondering if I should get either a GReddy or Plasmaman Inlet Plenum to shorten the plumbing and make it easier to plumb it all up. As i'm intending to put on a high-mounted GT30R on eventually, i wont be able to have the traditional over the rocker-covers plumbing.

Has anyone run either the bolt up plasmaman plenum head on the stock throttle body and intake runners - or the whole new plenum chamber from GReddy, which i've heard can sap from the mid-range.

Anyway i could also do a cut-and-shut of the stock plenum to have the plumbing in and out, but i haven't heard how this makes the car behave, because im fairly big on drivability.

Any help from the tech-heads is very much appreciated

Cheers

Edited by tuna_144
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this is my current set up, theres no room over the top of the engine for the pipes, the hood would never shut. This gives a long way for air to go, but i made it from narrrow exhaust tubing to keep the volume down. its only running 0.7bar on stock tubby now anyway.

(sorry huge pics)

200SXRB25conversion.jpg

SP_A0186.jpg

I am going to run gt3071r with supporting mods in a couple of months so have recently ordered a custom plenum creations rb25det plenum. Its a very good price and very good plenum, can run nice short pipes then, yay.

Edited by tom200
can anyone say 'mandrel bends'? LOL

-rb25

:lol: haha, i thought the same.

Check out the ISLEEP Custom Plenum Creation plenum, read the Greedy ones arent the best for even cylinder filling and performance in general.

is that fact or just rumor that the greddy plenums are puss?

wouldnt a major company make sure they flow well without damaging engines.. i just find it hard to belive such a big company would make utter crap if what some people are saying is true??

not having a go ether as i know nothing about the how they all flow... but with the millions of dollars greddy have im sure they could of made a better plenum if there suposidly (crap)..

I think more what they mean is that the GReddy inlet plenum's are designed for performance, and thus are really intended for top-end peak power. From the plenum designs i've seen fitted to nissans (mostly sr's), it appears to rob the car of some low to mid-range power and torque in favour of all-out power.

ive heard alot of reports that no matter what power figure rev range etc, the greddy ones for their money still flow no where near as good as other brands....Ariel can provide u with flow tests to show u...

heres a pic of mine with the 80mm throttle body, can get pics soon when its on the car

ben...

post-4085-1136678875.jpg

Hey people. Just a quick question as i've got an rb25det conversion from a sII r33 into my 180sx.  :D  Just want to know what to do with my intercooler plumbing. As i used to have a ca18det powered 180, i have the intercooler core and bottom arms of the plumbing coming up through the battery hole and the pod filter area on the left and right.

The thing is, im wondering if I should get either a GReddy or Plasmaman Inlet Plenum to shorten the plumbing and make it easier to plumb it all up. As i'm intending to put on a high-mounted GT30R on eventually, i wont be able to have the traditional over the rocker-covers plumbing.

Has anyone run either the bolt up plasmaman plenum head on the stock throttle body and intake runners - or the whole new plenum chamber from GReddy, which i've heard can sap from the mid-range.

Anyway i could also do a cut-and-shut of the stock plenum to have the plumbing in and out, but i haven't heard how this makes the car behave, because im fairly big on drivability.

Any help from the tech-heads is very much appreciated

Cheers

Geezus man, do a search, this subject is done to death...........hundreds of times.

If you are keeping to standard internals then the standard inlet is the best, for everything, max power, average power and throttle response. Want to know why........then try the search button. Want to know how it has been tested? On the car? On the flow bench? Then do a search.

This is one of THE best supported forums in the world, whatever subject you can think of there is a 99.9999% chance that someone thought of it long before you did. There are enough race car engineers, machine shop owners, mechanics, fluid dynamics engineers, etc etc that post on here to have the questions answered years ago.

:D cheers :)

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