Well I know there's been a ton of buzz and a mass of posts in regard to the Motordyne Plenum spacer. I hate to add to the everything but I've got a question for G drivers with aftermarket plenums and spacers. Potentially I don't correctly understand the true functions of the spacer but from what I can tell the main purpose of it is to correct the slant of the stock plenum and allow more air to flow to the front two cylinders. In the case of us aftermarket plenum owners (crawford, kineitx, etc) this problem is already solved. So what good would a spacer do? Would it actually produce any hp/tq gains? I just don't want to pay $230 for a part that I don't necessarily need or won't give me any gain over my current setup. Thanks in advance.

i would doubt you'd anything or much of anything if you already have an aftermarket upper plenum

Yea SickOne thats pretty much what I figure is going to be the case but I know for sure that there are several G drivers out there with Kinetix Plenums and spacers and maybe a few with Crawford Plenums. I'd be very interested to see if they agree with our thoughts or have anything to say to the contrairy. I in particular own a Kinetix V4 Plenum.

what about fit - I thought the Kinetix and The Crawford were alread getting pretty close to the hood... is there really room for more height ?

Yea just a little bit of room but not much. Tony reccomended the 3/8 with Kinetix.

I didn't recommend it but I know it the combination fits in the G35C. Only a dyno could determine the added value. My guess is that it can't hurt, but any added power would "probably" be marginal.

This combination needs to by dynoed to really know the answer.

Tony

Generally, a spacer is used to increase intake runner length and allow for more efficiency in the lower rpms and thus make more torque. If you look at a Mustang's intake, you'll see pretty long intake runners. They're designed that way so that it can make greater torque at lower rpms since it's cylinder head design is already limiting upper rpm breatheability.

This particular mod does not change the runner length. It only increases the flow area above the runner, allowing the runner to breath more easily for any given RPM it may be operating at.

Sorry for misinterpreting that Tony, you're right you had only mentioned that it 3/8 seemed to fit Kineitx setups. I don't want to discredit this part in any way because you certainly did a quality job and this part is incredible with stock setups. In the case of aftermarket plenums though you're right, we'd have to see some dyno numbers to ultimately tell. However from what I've read in this post and others it seems that a spacer with an aftermarket plenum a spacer won't make that much of a difference since then slant has already been corrected. The only advantage I can fore see is increasing the air volume of the intake manifold however this is limited by the lower collector and what the runners can ultimately "inhale."