custom plenum and fmic or not!?

[franks]

dilemna...........

i have a small question, if i was to get a custom front mount intercooler, is adding a custom plenum to REDUCE the pipework going over the engine worth it???

Will it be just as responsive with the additional pipework as it is without?

cheers,

[meggala]

if you are going for a mga big torbo and heaps of power yes other wise the stock one is good for 450 hp or so is that enough

meggala

[franks]

a custom plenum pipework

[franks]

Originally posted by meggala

if you are going for a mga  big torbo and heaps of power yes other wise the stock one is good for 450 hp or so is that enough

meggala

later on down the track there's possibility for a larger turbo, but for now im deciding against because i do want to retain bottom end...so you believe the plenum wont make that much of a difference to response over the "full" piping and OEM plenum?

[meggala]

thats correct unless you get a greddy one which are 2k there are a number of issues.

better to keep stock and use a crossover pipe

m

[franks]

please elaborate!

what does a Greddy one do that a fabricated one can't do? i mean Greddy is essentially a fabricated item anyway?

i spoke to mark at hills motorsport about inlet plenums and wether or not each of the injectors will be fed the same amount of air (which i believe is the main issue?) and he's very confident he's looked at that and addressed it...?

[Clint32]

Provided the custom one is constructed in a way that it is tapered down towards the back there is no problem with air distribution as the throttle body does not feed directly towards any runners giving them more air.

I did not notice any extra lag when i fitted my front mount with the long crossover pipe.

[franks]

clint you went from a custom plenum to a crossover pipe? or your commenting from standard i/c to fmic?

[Clint32]

When i went from a std cooler to a front mount with crossover pipe there was no noticable difference in lag, i am now making a custom plenum so i can make the pipe nice and short keeping the air cooler.

[franks]

ETA? would be interested in hearing your results!

[meggala]

the main issues with the other custom pleniums is the cars idle very badly. there is no inlet for the breather pipes from the rockers ( which doesn't conform to the epa. and they are alot of money for little gain. most people I have heard who fitted a custom plenium have had to go to custom ecu which in it self is not always legal. I have seen plenty of skylines make 250+ rwkw with the stock plenium. so why change unless as I said you want an all out race car.

btw if you can show me skyline with a custom plenium running the stock ecu and running well with cold start etc. I would be interested.

btw mat lowth on these forums is making 270 rwkw + with the standard plenium and probably more .

you car is fairly new and must drive beautifuly why ruin that if the are no major gains to be had.

meggala

[Guest DON91E]

Originally posted by meggala

if you are going for a mga  big torbo and heaps of power yes other wise the stock one is good for 450 hp or so is that enough

meggala

Thats true, iv heard something in the vincinity of 500hp+ you would only see a difference with custom plenum.

Frank, iv actually thought of this b4 and went to investigate it further. I was in the same position as you, installing a new fmic and wanted to get custom plenum only coz it was so much neater.

There are only really gains to be had (maybe even none) by having this custom plenum.

Its just 2 expensive and won't justify the $=hp improvement.

If your fussed your beta off just getting the intercooler pipes HPC treated to repel heat of something.

conclusion

Don't waste money on custom plenum, not worth it.

[hungry6]

actually, i can shed a bit of light on this thread, i've used both custom and modified stock plenum. the modified stocko is the better of the 2 , but it does requires lots of grinding work withing the plenum for correct air deflection vanes, where as the custom was an absolute heap of shit. but then the g reddy one looks the wrks tough, and as for response time, it beats the stock pipe over settup hands down and this is with a big fmic. i got pics if anyone wants to look just pm me.

[matlowth]

Re: the idle - That's spot on - that's because they no longer use the idle control component... Cold start is no good either...

re: my car - as you said - it's made 316rwkw @ 14psi as of last week, and still running the crossover plenum - so there is definitely better mods to do before you consider the plenum.

matt

Originally posted by meggala

the main issues with the other custom pleniums is the cars idle very badly. there is no inlet for the breather pipes from the rockers ( which doesn't conform to the epa. and they are alot of money for little gain. most people I have heard who fitted a custom plenium have had to go to custom ecu which in it self is not always legal. I have seen plenty of skylines make 250+ rwkw with the stock plenium. so why change unless as I said you want an all out race car.  

btw if you can show me skyline with a custom plenium running the stock ecu and running well with cold start etc. I would be interested.  

btw mat lowth on these forums is making 270 rwkw + with the standard plenium and probably more .  

you car is fairly new and must drive beautifuly why ruin that if the are no major gains to be had.  

meggala

[Guest INASNT]

Originally posted by matlowth

Re: the idle - That's spot on - that's because they no longer use the idle control component... Cold start is no good either...

re: my car - as you said - it's made 316rwkw @ 14psi as of last week, and still running the crossover plenum - so there is definitely better mods to do before you consider the plenum.

matt

Damn Matt u r a sicko! so i guess that new T76 is working well to get over 300rwkw at only 14psi!:eek1:

[meggala]

thanks for the back up Matt see you Sunday I hope you run well.

I'll givbe you a run if you give me 5 seconds start

meggala

[kabab]

The greedy ones have been flow test to make sure each cyclinder gets the same amount of air thats where the $$$ goes.

I think a greddy plenum and Q45 throttle body are about $1800-2000 ask Andrew i think he still has one ??

I don't know how much performance its going to give you but god dam does it make your engine bay look good

[franks]

in regards to the idle control component, from memory, hills were saying they do retain it - now wether i was misinformed, heard incorrectly or not knowing what im talking about is another story is it impossible to retain the idle control component on a custom plenum?

the message is very clear in what your saying. and that is, plenums are only beneficial with big HP and could, in some cases, cause more problems than anything.

i guess the answer i was looking for was wether or not the crossover piping is insignificant in terms of response. from the comments here it seems as though it isnt that bad....but i guess its just an age old thought that the additional piping is going to be significant...

[B-Man]

I brought this up again at Hills today and they insist that it is a good mod. Maybe it is OK with the Hills Stage 1+2 upgrades ???

Mark doesn't usually put his goolies on the line like that without something to back it up......

[matlowth]

Sure is! No more laggy either!

U coming this sunday?

matt

Originally posted by INASNT

Damn Matt u r a sicko! so i guess that new T76 is working well to get over 300rwkw at only 14psi!:eek1: