I've seen and heard about throttle body spacers, word of mouth is they work, but no one actually has one that I know. Has anyone used one of these, and if so did it help mileage or power?

 

i have one on my truck and i cant really notice the difference.maybe with more mods it may work but the jury is still out for me.




1990 f150 300-6fi a/t 2wd
k/n,lowered 2infrnt 4in rear
bfg 295/50r15 on ar 15x10 rims all around
accell coil,tb spacer,with more to come!!!!

 

I never heard about these--what exactly are they and what is the theory by which they are supposed to improve mileage and power? Is it like having longer intake runners for greater torque? I was under the impression the factory EFI manifolds had been tuned to maximize flow, taking into consideration the inherent resonance of the power pulses in the intake tract, based on cam timing, etc....

 

There are 2 reasons for carb/throttle body spacers. 1)insulate the carb/throttle body from the heat of the engine, and 2)to lenghten the intake tract to inprove bottom end torque. Ford went to great lenghts to maximize torque on the 4.9L, and from what I've seen and heard unless you have an extensively modified engine you won't see much improvements with a spacer.

TrailDawg
1993 F150 2WD
4.9L-Auto
Pro-Comp Stage-2 6" lift
Auburn Pro-Series Diff. w/4.56:1 gears
35x12.50x15 General Grabber MT's

 

Thanks, Traildawg. I'm with you, thinking heat is not good for the incoming charge, so both those reasons make sense as theories behind intake tract spacers. However, this makes me even more curious as to another question I have posted in a different thread, which is why the Clifford performance intake manifold is water-heated? This would seem to contradict the heat insulating/reducing properties of the throttle body spacer.

Anyway, thanks again.

 

Sounds like I might as well keep the money in my pocket for now. It's nice to be able to draw on someone elses skinned knuckles, thanks for the replies.