Best N/A performance mods?

[nismoman18]

it seems there are really only 2 chocies one is kobe i think thats how u spell, and the other one is like pac performance or sumthing ??? aask gregg who organised a group buy once, i missed out

[Greg]

coby extractors (about $350) - www.partsco.com

fujitsubo extractors - (about $2500) - www.takakaira.com

i only have experience with coby extractors (quite a few others on here have them) and they gave a lot more low to midrange power making the car a lot quicker for normal, everyday driving. i maybe lost a little top end power, but it may only feel like that due to the increased low to mid power (if that made sense). i highly recommend them.

[pstanbis]

i too have the coby extractors, and gregs right, low-mid is great, however i didn't notice that drop in top end - it still kicks at 4-5 thou, and stays on a little longer if anything. the 2litre might behave a bit differently though.

I was thinking about that sucking noise under power though - has anybody stood in front of the car and revved it to see where the noise is coming from? i still have the stock airbox and intake snorkel, and the noise is still quite pronounced. Might be noise of flow through the extractors themselves rather than the intake...? ill have to have a closer listen on the weekend....

[Greg]

what i was trying to say is that the top end power was probably unchanged but it just felt less in comparison to the power that was made available in the low to mid range. still making no sense!?

pstanbis, the sucking sound is very annoying isn't it i was told by an exhaust shop that it is resonance in the extractors. ways to reduce the noise (by muffling the sound):

. wait for them to be coated in carbon/exhaust residue. mine quietened down after about 1500km's, but only a little.

. wrap them in exhaust wrap. i considered this but its quite expensive, if not done properly shortens the life of the extractors. its a bit of a hassle to take the extractors off, clean them of all rust etc, then paint, wrap and paint them, and then put them back on.

[Krys]

What kind of sound is it? You'd think a sucking sound would be a cool sound.... lol whats so annoying about it?

[Greg]

umm well its not really sucking its kind of like a shrill vibrating almost metallic sound...very hard to describe. you might like it but its not my thing

[Krys]

aslong as it doesnt send spastic vibrations through the car i'll like it... plus the stereo and the exhaust will "cancel" it out .... lol

[Greg]

haha yeah that's right just turn the system up a bit and it disapears, funny that

[MearCat]

I was annoyed at the fact that it's very hard to run a cold air pipe from lower bumper to the filter box - coz as you all should know, the air flow through the filter goes DOWN. Instead, I got a K&N pod and made a FULLY SEALED (screws) and INSULATED heat shield from aluminium sheet and ran a 3" PVC pipe up onto the pod. Runs fantastic on the higway.

[Greg]

mearcat i am unsure what you mean by "air flow though the filter goes down"??? your setup sounds similar to mine, except i'm missing the 3" pvc pipe. if possible could you post some pics of your 3" pvc pipe because i want to make this. thanks

[MearCat]

Greg,

Cripes - I'd love post a pic but I don't have a digital camera. I'll Explain it differently :

Air enters the scoop just above the radiator and flows into the top half of the filter box, passes through the filter into the bottom of the box, then runs off to the throttle body.

A cold air feed pipe normally runs from the bumper area directly into the filter box, but with the above setup the pipe it's a lot harder to get a large sized cold air pipe to feed the top half of the filter box. So I just went for a pod and a pipe that feeds the pod.

Does that explain it better?

[Greg]

much better, thanks mate

[NA_R33]

hey greg i now have that sound ur describing. i got the resonator and middle muffler taken out of the hks system and it now sounds so bad i dont want to drive it. i went back and got a new resonator which almost cured it but the car is too quiet now, i was thinking of selling the hks system but im now not gonna bother as the new engine is on the cards.

[Greg]

hey john sorry to hear your exhaust sounds shit! i was considering removing the middle muffler to give it a tougher sound but now i've read that i won't bother.

i finally discovered what was making the sound, this might help you, here's the story:

I was driving along and all of a sudden my exhaust got REALLY loud. i stopped and looked under the car and sure enough mr muffler (who fitted my extractors and cat) had failed to use split washers and the bolts on the cat had vibrated loose, letting exhaust gas escape. so i drove around for a bit enjoying the exhuast note () and then took it home and reversed onto ramps. i removed the cat and discovered two things:

1. mr muffler had combined 2 broken gaskets to try and make a good one, it obviously failed.

2. in the cat there was heaps of little drops of weld mr muffler had failed to remove.

these 2 items were the cause of my dodgy sound - the leaky gasket and the weld droplets. so i reused an old gasket i hard lying around (it was heaps better than the ones mr muffler installed) and vacuumed all the weld droplets out of the cat. the exhaust sounds awesome now and i'm going to take a sound clip soon and post it up (just for your joe, if you're reading this ),

cheers

greg

[Greg]

oh yeah and for those in victoria:

AVOID MR MUFFLER IN LILYDALE

[Cortide]

Greg you should have come round, would have liked to hear your car

[jacko]

I was going to get some extractors soon!

Why the huge difference between coby extractors and fujitsubo extractors??

Does it make a big enough difference to warrant the noise and money?

Secondly I only have a stock exhaust and would change at the same time! What brands would be good at reasonable price?

Can any one tell me the KW given before or after? I really have no idea what the power of my NA R33 is???

[Smadge]

I'm thinking i'll go for the K&N panel filter and try to incorporate twin air vents on each side of the bonnet for better air flow. Might try getting some stiff pipe hooked on underneath the bonnet going from the air vent to the air box. I might also try some flexi pipe running from the botom of the bar into the engine bay. Just ideas....

Also, can anyone recommend some Brand name extractors and their experience with them? what kinda power boost should i be expecting?

i have a 91 R32 GTS with a RB25 n/a and i have just changed my ashmatic air filter to a proper k&n filter and the power difference was amazing. and i have also had fited a set of custom made pacemakers fitter to it about a year ago and it has a 2.5" exhaust right through to a super cat muffler. sounds awesome. power increase wasn't neck breaking but better. but had way better sound and in gear acceleration.

[Viper_5345]

everyone just stop replying on here??? come on greg were is this awsome car sound

[Greg]

ahh i still have it actually but its about 20mb waay to big to post up!