What other plenums besides Greddy/Trust?

[GTS-t VSPEC]

I didn't say it was a problem, as I believe the standard runners are quite good, but it does mean sending your original plenum over.

[T0nyGTSt]

It depends on how you feel about it.

The story goes that if you ask for a custom plenum they generally fabricate the top end, bolt it onto the original plenum bottom and them feed the pipe next to your water bottle. They give you back all the bits left over.

But at this point the Greddy looks like the goods to me.

T.

[ed]

The greddy unit is under a grand, less than what sub-zero want.

[judd]

im sorry...just I think that pleneum would have a very selected market....like similar concept to jap back yard jobs....drift only, as there the bois which dont give a f%&*. but just cant see someone making profit on one of those pleneums.

[judd]

yeh shipping + duties Ed? still under $1000? oh and forget about installation?

you can quote all the prices you want. you just give people false assumptions, let me see you do it less than a grand!

[GTS-t VSPEC]

Under a grand? That seems very cheap, where from?

[ed]

Originally posted by judd

yeh shipping + duties Ed? still under $1000? oh and forget about installation?

you can quote all the prices you want. you just give people false assumptions, let me see you do it less than a grand!

gimme $990 and i'll bring one over

[T0nyGTSt]

Yeah I'll do a deposit right now for $900... seeing as Hills want $895 for their 'top cover only' unit.

T.

[judd]

and install? ed i have an R. I believe the GTR plenuem is cheaper as i have 6 throttle bodies...alone those lines..

[RNS11Z]

does the rb26 inlet manifold fit??? im guessing this would be way cheaper then the greedy or trust plenum and still provide similar performance.

[T0nyGTSt]

Install can get expensive as they often need to fabricate new IC piping and even cut chassis rails (eek!).

T.

[GTS-t VSPEC]

You can make them fit, but the plenum is not cheap, then you have to modify it.

[ed]

actually no, sorry. I will bring it over for $990 for someone else and I will show you the receipts all the way through the process.

[T0nyGTSt]

The GT-R one would also negate the need for expensive injectors, fuel rails etc.

You just have to find one. This is assuming it bolts right on. I really don't know.

T.

[Sydneykid]

Hi IGTS-t VSPEC you posted "I have the Greddy one and have found a substantial gain in the mid-range just by adding it, plus at high rpm it doesn't fall off power as quick."

I get that comment a lot from people, so I like to dig a little. Did you do anything else at the same time as putting it on? Tuning? Intercooler? Pipework? Heat shielding? Boost? New spark plugs? Oil change? etc

Moving on to, "Can't say what the distribution to each cylinder is like though."

That's always a tough one, the single lambda sensor only tells you the average A/F across all 6, not if one is lean and another is rich. We use a high temp laser pyrometer on each of the exhaust manifold primary runners. If the distribution is good then the temp of each pipe is the same. A lambda sensor in each pipe would be better, but unless the manifold has the fittings that's a bit difficult.

Even using the temperature measure we get some arguably poor results, 40 degree differences are not uncommon, compared to a standard manifold of less than 10 degrees.

When we do this we juggle the injectors around ie; stick the ones with slightly more flow into the "hot" cylinders as they are the leanest running. Two "wrongs" sometime do make a "right", except those cylinder will make more power and thus have more cylinder pressure. This leads to unbalanced crankshaft loading and increases the chance of harmonic related failure. Better than detonation on 1 or 2 cylinders though.

Hope that adds to the discussion

[GTS-t VSPEC]

Sydneykid,

I had to change the pipework at the same time, but my power doesn't drop off till much later than people with simliar designed pipework and stock plenum.

I can see what your getting at, and it's always difficult to tell what is the true impact of a modification.

I was lead to believe that even the standard plenum design led to overheating of the no.6 cylinder, hence why most piston problems occur there.

[judd]

Originally posted by ed

actually no, sorry. I will bring it over for $990 for someone else and I will show you the receipts all the way through the process.

cool want 40c?

not to be rude, but im sure i can do better than $990.00 point is that after install, not to meantion duties + tax if it gets caught up. Just like an intercooler I got for Z32 it got caught in customs as they didnt believe the reciept. Worth the risk? Altho its a Pleneum is it worth the risk? who are you really doing a favour?

[Sydneykid]

Hi GTS-t VSPEC, the No 6 problems we have seen have been GTR's, never seen any evidence of unevenness with a standard RB20/25 inlet manifold. Plus on the GTR's it only seems to be at high boost levels (over 1.3 bar) up to that level and it seems perfectly OK.

The bolt pattern on the inlet manifold to head is different between the RB26 and RB20/25, so it won't bolt straight up. Lots of fabrication/welding required. I was very interested to read the comparison on an RB20, in the latest Zoom, between the RB26 and RB20 inlet manifolds. The car produced more power everywhere using the RB20 manifold.

I have seen similar results with SR20's and some big brand name inlet manifolds and plenums. If they can't get it right on a 4 cylinder, what hope is there on 6?

This is a good thread, worthy of some time.

[GTS-t VSPEC]

Yeah, I read that article aswell, as it does make you wonder whether some of the bigger companies do any flow testing at all:D

Although the RB26 was better down at low rpm.

[ed]

Originally posted by judd

cool want 40c?  

not to be rude, but im sure i can do better than $990.00 point is that after install, not to meantion duties + tax if it gets caught up. Just like an intercooler I got for Z32 it got caught in customs as they didnt believe the reciept. Worth the risk? Altho its a Pleneum is it worth the risk? who are you really doing a favour?

Not to be rude? :bahaha:

You got a PM.