I'm about to purchase an intake plenum spacer for my 2003 g35 coupe. I wanted to know which intake plenum spacer you would recommend? what size? where i can get a good deal on one? and any additional information I should know before buying and installing one.

 

3/8" Motordyne Plenum Spacer. Easy as pie to install(they're all pretty much the same). If you get the 1/2" spacer, you'll have to remove your engine cover because it will no longer fit in the bay with the spacer on.... and the gains are exponentially smaller as you go with taller spacers above 3/8". In my opinoin, it's worth it to go with the compromise... 95% max plenum spacer performance that you get with the 3/8" spacer + 100% OEM engine bay look compared to the 1/2" spacer which is probably like 98% plenum spacer performance with a non-OEM engine bay look.

 

motordyne 5/16 used to have a better lower rpm while the 1/2 is more of a higher rmp

 

skunk2 is another good spacer. have to remove engine cover though

 

Skunk2 5\8 and hell with the engine cover

 

Good luck getting your hands on a Motordyne 3/8" spacer.

You can't go wrong with Motordyne's spacers.

Skunk2 spacers, on the other hand, are way too big. Bigger is not always the answer.

 

MD 5/16" is the best overall IMO.

 

powerlab's 3/8's spacer. best bang for the buck for under 200 bucks. Just installed one myself

http://www.my350z.com/forum/showthread.php?t=345425
https://g35driver.com/forums/body-interior-exterior-lighting-diy/131570-diy-custom-diameter-halo.html

 

Okay... I live in Maryland and it is a four season area. Which spacer kit do you guys recommend?

 

Motordyne 5/16" spacer. . .and MREV2 depending on what engine you have. . .

hands down

excellent quality product
excellent customer service

waiting for their exhaust to come out too!!

 

If you want the power all throughout the RPM's go with the Motordyne's 5/16... if you want the power at the higher RPM's get the 1/2

 

whats the difference between the motordyne copper thermal spacer and just the thermal spacer?

 

I was just about to get the 1/2" copper spacer for my G35 Sedan. I am wondering how easy it is to install. I am pretty mechanical, but most of it is on my muscle car.

 

The Copper is fully automatic and never needs to be adjusted according to weather conditions (hot or cold). Use this version when cold weather is a common occurance.

But if you live in a place like California, Texas or Florida you almost never have to switch the Coolant Control Valve because the weather rarely gets cold enough to freeze. And in the rare occasion where it does get really cold, you can just turn the CCV to the on position.

 

If you are familiar with muscle mechanics, this will be easy for you.

Its really not hard to do. Just open up the plenum like a clam shell, remove the lower plenum to install the Aramid gasket (if you are getting one of the Iso kits), reinstall the lower, put in the spacer and put the top plenum back on. Bolt it all down and you are done.

Its not really engine work. Its air intake manifold work that basically involves two pieces of intake manifold.