Is anyone useing or tried this TBI spacer. I'm wondering if the area between the bores produces the same properties as a TPI Air Foil. Seems to me that it would.

http://www.cfm-tech.com/tbispacer-1.JPG

 

IMHO, gimmick. The manifold is connected anyway. The foil of a TPI is intended to smooth out the corners of the throttle body. The air had already entered the TB when it passes the spacer.

 

My main question is how much would this help atomization? My next question is what size are the bores... 1 11/16" or 2"? I have e-mailed CFM-Tech and am waiting on their answer.

 

I have talked to them before and they are very helpful. I have a spacer and found it to be an improvement. I made my own. I think the little notch is gimmicky.

 

TimRS, nice collection of LO3's. Thats pretty cool. Good luck with them!

 

Thanks Treview1. I've got an open element ready to go on the 5-speed but just haven't had the time to do it. I'm considering this spacer also. I'll try to keep everyone posted.

 

The bores are 1 11/16". The Holley 670cfm TBI and the GM 454 TBI have 2" bores

 

I just got a reply from CFM-Tech. This is their reply:

"The bores are 1 11/16" and is 1" high. This plate will make as much, sometimes more, hp as adding a larger 2" tbi unit. The secret is not in the throttle bore size - it is in how much air goes thru it.

We suggest purchasing the Injector Spacer if the stock tbi unit is used. A high flow air intake will also be beneficial. More air = more power!"


Any opinions on their claims?

 

Is it better? I don't know. I have a 2" bore spacer that is 1" high and didn't notice any significant gain from it. I had to have the spacer to fit the EGR valve because the TBI unit was too low.
Did it make a difference? I can tell you that from my experience, that it really didn't make much of a difference at all on my system.
Maybe it does. But not any seat-of-the-pants difference. I couldn't tell any difference before/after my spacer was put on.