plenium/Intake manifold Q's

[jansenrw]

Just reading around on the forums, but I would love to know some real advice on plenium chambers - maybe ADrian or Jason can put in their .02....

Apart from the stock ITR plenium, and ofcourse ITB's, what is a resonable compromise that is readily avail and offers decent gains over the factory piece?

The plenium should be for a mildly built B18 motor. Any advice would be muchly appreciated.

Thank-you

[tinkerbell]

need more details on engine specification!

for a "mildly built B18" - the itr plenum is fine,

why do you think it is restricting power?

[jansenrw]

ok, engine has full valve train completed, mild cams, raised compression, i/h/e computer- few of the bells and whistles. I gather it could possibly be the intake or exhaust holding the car back as it seems the overlap in the toda B's appear ok. As for exhaust, running spoon headers... ????? possibly try toda?????

intake is def ok, so next thought was the inlet manifold. am i on the right track? ALso have looked into import builders extruded i/m. think the site is importbuilders.com

[tinkerbell]

can you provide a dyno chart?

[tinkerbell]

the JG manifold would be a good way to see if it is the area which is going to improve,

it is not expensive, so it is a:

dyno engine
bolt off ITR manifold
bolt on JG manifold
dyno engine

examine results... then maybe play with cam gears and AFR's...

but if chasign lots of power, i would suggest thinking about getting toda headers, or maybe SMSP from usa...

[tinkerbell]

but hey, i am only talking about 'in theory' stuff...

others might have 'in practice' results...

[jansenrw]

hey any .02 is adding to my .02

toda headers are noted....

whadda you think about the extruded itr manifold???

[tinkerbell]

i think an extrude honed ITR manifold would be harder to off-load than a JG one, in the event that it did not work/provide gains...

but i would recommend getting head port work before extrude honing the IM...

[tofuR]

hey jansen,

Just chiming in for my 02,

First of all, for what is holding back your system?
What kind of power are you putting out now, or more importantly how does your car perform on the strip or the track ? any comparisons you can make with a stock dc2r? or a similarly built dc2r that is out performing u ?

reason i ask this .. is how do you know something is .. to use your words
"holding your car back"?

having answered that .. if i remember correctly u have a crate motor .. minor polish job from spoon .. yes?

maybe before u consider going to upgrade the actual intake manifold, you should consider doing a mild port to suit your cams, open them up a little ( be very careful who u take them to) .. get a 3 angle valve job, to ease the flow.. and also get a proper sized tb (assuming u r running the venturi spoon item) .. then consider upgrading the intake plenum itself if required .. thats the intake sorted..

as for the exhaust .. i am running Spoon as well .. and i dont know if i'd consider changing to toda as an "upgrade" they may be on the same level.. or toda may be marginally better.. but definitely not worth the hassle/cost involved..
only reason id rate a toda over a spoon is the ground clearance issue..

as dave mentioned.. SMSP is definitely worth going.. there are other options such as RMF narrow,or the rage tube headers, or if u wanted to go local .. speak to dyno dave .. he can make a set of his diamond headers for u .. a great piece for a good price..

but in the end .. having said all that .. doing that will net u .. 10kw atw?
well .. woop-dee-f*n-do ..
having been down that track .. i wouldnt recommend delving down the path of trying to squeeze any more power out of it .
id try to maximise what u have..

e

[mecca]

jansenrw just post your dyno graph dude.

I think your posting very reasonable numbers, but I guess after the weekend you are craving a little more!

Nothing like seeing a supercharged M3 on the dyno to make you want a little more at the wheels

[jansenrw]

hahaha... thanks guys,

Tofu R, she has had head work done, what your saying does make definate sense!!! I think there is a time to draw the line. Hate to say it but maybe its time to give up on the R and start a new with another project. I guess its always a what if??? I mean theoretically if i ad smsp headers, get quads e.t.c there goes a few more K....

As for my car, I dont think its being out performed but I definately do feel that it not quite up to where it should be. Valve train is completely upgraded, bottom end aint stock, compression is up. I guess the easiest way to put it is whats left.

Possibly upgrade headers and better exhaust, then quad itb's, toda c's.. thats just about all thats left before is change block or just get a bloody k20a...

hmmmm.

[sangers]

k24/20, dooo it.

[tinkerbell]

just buy and fit a JG intake manifold and see what happens!

[freakie]

jansen, I ran into these problems early into my build and I think I ended up wasting more money chasing power than if I had just started fresh.

The tuner who now does all my work constantly tells me about the importance of matching parts, ie big collectors on exhaust manifold is going to be useless unless the pulses can be met on the intake side etc etc.

Might be better to start with a plan and an engine and start like that