I've heard that installing the crawford plenum will cause a weird sound at idle. If it's true, is the sound annoying? Will you be able to hear it with the windows up? Anyone with the plenum installed that can give me their opinion.
Thanks for the info.

 

Yes, it is annoying. Sounds like your valves are out of adjustment. I am taking mine off and going back to stock after Doug sends my stock one back. The gains are overrated. Wait until a real cast plenum comes available from Nismo or some other factory authorized supplier. Or just go FI and forget about it. Wait until they figure out how to do that too, since guys are starting to blow up. The best mod so far has been the stillen dual exhaust. Very noticable gains and no metallic tapping and whirring noises. OK on the track, but not around town.

 

"OK on the track, but not around town."

What is, the Plenum or the Stillen exhaust?


"Use the Forced Induction Luke!"
-Jedi
2003 G35C, 6MT, Navi, Black Obsidian/Graphite

 

The plenum. Valve tapping and other undescribable sounds not only at idle, but under load. You will hear it in the car and people will ask what is wrong with your engine, sounds strange. Even if it does give you 9HP peak, I dont want to hear it anymore.

 

Mine has been on about six months now. I hear no strange noises. When I installed it, I heard no strange noises, although it was mentioned at the time that some people heard them. The power it adds is defently not underrated. It was the Best Bang for the Buck mod that I have done. I wouldn't part with it. I'm a believer. Karl is the first non-believer (that has used the plenum) that I have seen. Sorry Karl, but I love the thing.

Lou

 

Same for me. I love it, and wouldn't part with it. Mine gives a little rattle noise at idle up to maybe 2k, but not objectionable and probably because i've left my cover off. The plenum itself must amplify what is there already, but as I said it's not objectionable at all.
Good luck and merry Christmas.

<font color=red>G</font color=red>S<font color=green>M</font color=green>
<font color=red>G</font color=red>S<font color=green>M</font color=green> <font color=black>Silverstone Coupe</font color=black>

 

It sounds just like disel engine. The gain is noticeble at high speed.

Black NismoV35

 

The other thing is if you are going to go FI or N20 you can't get the plenum and not bust the engine at high rpm...
I think if you don't mind loosing some of the beautiful sounds of the vq35de then go with the plenum for 9hp average and 23hp peak gain... but also gaining diesel sound.
otherwise:

Wait for another option, or invest in nice exaust, and better cats...

Peace
HAPPY HOLIDAY's ... Merry Christmas
-Eric

'03.5 Silver/Black | Prem | Perf | Aero | Stillen Hi-Flow | Z -Tube | Grounding Kit | Nismo Oil/Radiator Caps | Solid Allum Pedals | Diamond Matts | Tints | Valentine1 | Hide-Away License Plate!

 

The questions beg: How can you effectively and inexpensively quiet down the Crawford plenum? What kind of noise reduction can be applied to the plenum that will not melt from the heat (I was thinking of BrownBread, but it seems like it would melt and goop up the plenum)?
Anybody try some solutions?

jjellyneck

 

As for me, I agree with gsedanman as I love my plenum and definitely feel the benefits of the upgrade. I wondered about the noise difference as well, but have NEVER been able to hear any difference at any rpm...maybe it's me, or the only thing I can think of is that my particular combination of mods (see my sig) quiets any noise others have experienced, or, like gsedanman, I have taken off the engine cover, so perhaps that's what's bouncing up and down on the new plenum??

My $.02

Emile

'03.5 6MT Coupe|Caribbean Blue w/Graphite|Prem. |Nav|Aero|Hardwired V1|Alum Pedals|Injen CAI|Grounding Kit|15% tint|Borla Exhaust|Crawford Plenum|Unorthodox Ultra Racing SS Pulleys

 

Sounds like my Christmas present isn't a waste after all. I may have to marry this girl!

 

If she gave you a plenum for Christmas, by all means marry the girl. You've found yourself a keeper.

Lou

 

I think the diesel engine noise comparison is unfair, at least on my car. I hear no difference. No one has complained about it, even the dealer.

 

I just intall my Plenum today. I heard the Noise too. It is sound like disel engine. Is it normal to have this sound? Why some people heard and some don't?

 

lol good luck sixfive: )