I understand how these work but I wanted a couple things cleared up before I think about buying one:

1. Is 5/8th the best size to get? What's the difference between that and other sizes? (advantages/disadvantages)

2. Crawford seems to be accepted as the best plenum for our car, is that correct?

3. Best place to order these since ebay seems to have nothing but Skunk2. (not that theres anything wrong with them)

Thanks,

Nate

 

I have an MD spacer for sale

https://g35driver.com/forums/archived-sales/128340-fs-1-2-md-spacer.html

 

Go to motordyne site to read about them. Year of car makes a difference. 5/16 gives about as much benefit as bigger ones with no hood clearance issues.
Lots here about spacer. Do search.

 

get the skunk2 and you'll love it. i have it and my car sounds and accelerate better than stock. just because it's cheaper than motordyne does'nt mean its less of a product. i'll bet it makes the same hp bec its engineered for the same purpose. correct me if i'm wrong......

 

do it right with motordyne...

5/16 for even power

1/2 for slight loss in low end but more in top end

 

Don't forget about the APS tallboy plenum. That is a nice cast unit. I have seen both it and the Crawford and the APS is cleaner and appears to have better machining. Also, with a full plenum you have less leak potential since there is only 1 gasket surface instead of 2 with a spacer.

If I didnt already have the MD 1/2", I would have the APS. They were just too hard to find back when MD came out with the Iso-therm. Make sure to insulate the lower plenum to the final cast injector housing with a thermal spacer no matter what you go with up top. It really keeps the whole induction area cooler.

 

+1

I had one from my spacer and kept it on my SC, now it will go back on the plenum for the new change.

 

I guess I never weighed the pro's and con's of a spacer versus the full plenum. What is the price difference between these two? I am leaning toward the Skunk 2 5/16, on ebay it is about $190 shipped.

 

With the Skunk2, did your car sound deeper or what? When I got my intake it made a huge difference in the sound

 

Until we see a comparison we will never know. It can't hurt to let those front cylinders breath better though.
One reason the MD 5/16 is popular regardless of price, is Nissan Sport did a full comparison of several types and found it gave the best response overall across the RPM range.
The Skunk2 and a couple of more recent ones were never tested. Hopefully they will be soon.

 

the sound is deeper and louder but in a good way. it sounds like a v8 mustang but nicer. it stil has that sweet g35 ROAR... but i don't know how it will sound with your intake bec i only have a ztube and k&n filter.

 

You guys must be on drugs. A spacer and intake isn't going to make your car sound really different,

These are feet-wet-mods. You'll feel a little more pull, and your exhaust may be almost un-noticeably louder.

I did intake, High-Flow Cats, and Plenum all at once, I could tell my exhaust was a little louder, and my intake, and engine noice was slightly louder, probably due to that huge plastic thing being taken off the top of it.

a V8 mustang... get real. have you ever driven one??

 

actually, just about everyone that has a spacer, including myself, has noticed increased noise from the engine bay after the install.

the spacer should not increase your exhaust sound at all. that was your high flow cats...

however, i do agree. it doesnt sound like a v8 stang...

 

I totally agree with all above. I just installed my APS plenum a few weeks ago and I'm lovin' it. But honestly, the Crawford plenum is less expensive, and seems to perform the about the same as the APS, but I'm still glad I went with the APS.

 

Crawford