some are claiming these make a dif when between the GT500 TB and the Saleen SC...do you think they make a dif

 

I know a spacer is needed for a stock manifold and the GT500 TB and the saleen mght need one also.....making a difference i am not sure about, but it will allow you to add the TB itself since the bolt pattern is slightly difference on the GT500 TB

 

i dont think it is needed...i just got in my project and you can see it is bolted directly up..

[IMG]local://upfiles/59163/789AA5E1985E44FEB3BE88F4F731D18A.jpg[/IMG]

 

Yeah i would say you dont need it, personally i dont see the spacer doing anthing at all them....contact JDM about it maybe

 

Matt is right. The only thing I'll add is although you will see gains from the larger TB (properly tuned of course) you really won't see maximum gains until you fix the whole roof.

What I mean by that is if you have a bad roof and you fix a leaky patch - your not really solving the problem. So you get a bigger TB that allows a lot more air - you are still restricted by your meter, manifold, and intake. It's like putting a bigger opening on a 3" hose - you may get a little more flow, but you're not going to get as much as if you switch to a 4" hose, a bigger spout, and increase your water pressure. Sounds lame, I know, but that's the best way I can think of to describe it.

I guess the bottom line is that in my opinion, it's not really worth doing just a bigger TB unless you are going to at least do the intake and meter along with it. I mention those cause they aren't as complicated as also doing a bigger manifold also which is the way to get the maximum flow but is also a lot more complicated.

As far as the specific question - typically, the only reason to use a spacer is for fitment, not for gains.