Originally Posted by bigtruck311
throttle body spacers hurt your performance by slowing down the intake air volocity among other things they will do nothing to help on modern fuel injected engines
I'm not so sure, even though we all think the spacers are useless. here's a quote from Sean Hyland's 4.6 book - he is referencing a 1" spacer between the TB elbow and intake manifold
on a 4.6 Mustang.
" There is power improvement of 4 - 5 hp to be found with a spacer, likely as a byproduct of increasing the plenum size, which is too small to be ideal."
So, there may be an insignificant gain of a couple of hp.
If it were me, I wouldn't put one on for that small gain on an otherwise unmodded engine.