Throttle body porting
there is a radiused "lip" on the filter side of the throttle blade.
this causes a small restriction...maybe 2mm on each side...in the TB.
but if you do the math, the difference in surface area between a circle 71mm in diameter (2mm narrow on each side) and one that is 75mm is 10.4%
so that's a healthy amount of flow.
heres a diagram i made to illistrate:
and the finished product. i did it myself...just threw the whole TB on a lathe and machined down the lip.
this causes a small restriction...maybe 2mm on each side...in the TB.
but if you do the math, the difference in surface area between a circle 71mm in diameter (2mm narrow on each side) and one that is 75mm is 10.4%
so that's a healthy amount of flow.
heres a diagram i made to illistrate:
and the finished product. i did it myself...just threw the whole TB on a lathe and machined down the lip.
There's alot more to it than just removing the ridge if you want to see some decent gains. Here's mine that I did back in 05. Sorry for the shitty cell phone pic, I need to take a new one.
Notice how not only did I remove the ridge in front of the blade, but I also increased the size of the entire TB opening. See how much thinner the outer edge of the mouth of the TB is? Then on top of that I did the half-shaft mod, the bumpstop mod, and touched up the actual blade itself.
Notice how not only did I remove the ridge in front of the blade, but I also increased the size of the entire TB opening. See how much thinner the outer edge of the mouth of the TB is? Then on top of that I did the half-shaft mod, the bumpstop mod, and touched up the actual blade itself.
