Bellhousing

[JohnRoderick]

I assume you are drilling a hole through the liner too. If so, are you worried about compromising the integrity of the liner?

Are you also saying that other than RT, the air gap does not impact performance at launch? So RT aside, there is no difference between launching with 0.030" and 0.060" air gap?

Originally Posted by Jim Caughlin

Regarding air gap, yes you have to drill a hole to check clearance and also note that after you drill the hole, you have voided getting the bellhousing recertified. As you are mainly looking for the minimum air gap, I have a round rod (that is the minimum gap diameter) that fits through the hole easier, I ground it to a point at the end so it will slide into position easier. Bear in mind that if you are shifting without the clutch (which pretty much everyone is) that air gap is not that big of a deal, mainly I use it as a delay box for fine tuning reaction time.

Jim Caughlin
SS 6019

[Jim Caughlin]

When you go to full RPM on the starting line, the counterweights are going to close up some of the air gap which is why you need the gap in the first place. Also the reason why you need extra gap in the bellhousing for the throw out brg, otherwise the brg would start contacting the counterweight fingers at high RPM. Even with the line lock set, if the air gap is too tight, you can feel it tugging on the brakes, early disc failure at least. If you have the minimum reqd air gap, it's just a matter of RT from there. I always state my disclaimer: your results may vary...

Jim Caughlin
SS 6019