Forward Facing Plenum

[KLR33]

i have done this more than a few times and have never had a bad result

the biggest gain i noticed was greatly reduced lag

the reasons i did it

most of the copy plenums needed as much work, some more than the standard one

less pipe work (obvious)

tidy up the eng bay

it worked for me.

but it would be interesting to see flow bench results

then again who ever does them will do them differently

so testing 1 does not mean all r good or bad

all that being said i m using a greddy copy on the thing i m building now

but it is for height and eng bay room issues

[mad082]

both afr and egt's will both be directly reflective affected of the temparature in the cylinder, otherwise you wont have the detonation

does anyone have one of these floating cut and shut plenums about....i am curios to test one?

come to think of it, i have a complete spare r33 inlet, i will make one and and test it by the end of the year...i have plenty on at the moment so it will have to take a back seat for the time being

you can get detonation even with a good AFR if the cylinder temps are too high (caused by either high coolant temps or too much timing). the missus used to have a datsun stanza and when the headgasket was on it's way out and the engine temp was getting a bit high, if you drove it hard and then pulled up and turned the key off it would keep running due to detonation caused by hot spots in the cylinders. with fuel injected cars you don't get that happening because once you turn the key off everything shuts off and it can't keep sucking fuel into the engine like with a carby.

[ISL33P]

KLR33 - i will do some flow testing of it. the entry, as long as they are all cut flush at the front, will generally give the same results, give or take a few

that is usually caused by excessive timing given the engines running condition, my brothers sigma used to do the same thing.

luckily with a fuel injected car, we are able to control a lot of it under all different conditions

[KLR33]

KLR33 - i will do some flow testing of it. the entry, as long as they are all cut flush at the front, will generally give the same results, give or take a few

when u flow the modifyed one ,it would be good if u could test a standard one as well

for comparison

i and many others would be keen to see the results

not sure where u r located but if its in sydney i have standard 33 and 34 inlets u can borrow to flow

[ISL33P]

im in wollongong. i have a spare 33 which i have already done some testing with, but unfortunately the shop i done it with is no longer around and since a flow bench is like a dyno, i would prefer to do a comparison on the bench.

its on my to do list

[dilfukin]

I was just wondering if any testing has been done between stock side feed throttle body position,and moving to front facing?

Cheers

[ZILR-34]

by modiflying ur stock intake manifold to a front facing one you will lean out ur rear cylinders. one way u can tell is take it for a drive and pull the spark plugs out and u will see the first 3 cylinders will be black from to much fuel and the rear 3 cylinders will be white from lack of fuel.

one reason i got the Plazmaman Plenum kit on my old R32. not only cut down the turbo lag i also gained 15hp.

[KLR33]

KLR33

seeing as you have doen this mod before, what did you end up doing with the coolant/air bleed that usuallu sit near the TB?

put it in the bin

didnt run water through the TB

if i need to bleed the coolant system just undo the small hose clamp

[SRX720]

what's a replacement plenum worth on one of these out of interest? 15 hp is not to be sneezed at, and the crossover pipe looks stupid.

[tryingtobebest]

This is very cool!

[PhilKenSebben]

Yes, it is, and I'm rather interested in the results...

Was the bench flow test ever performed? This is a pretty old thread.