collector extension length?

[drag-n-cuda]

Anyone with experience could recommend length of collector extension for my 340 4 speed 1 5/8" primaries, 4.56's 10x28 Eagle slicks, 750 DP. Does the paint the stripe down the lenght of the extension, run the quarter and where the paint burns off is where you should cut the pipe for it's optimum length. I want to bring enough extension, but not over do it.

Thanks,
drag-n

[Mopardad]

Start out with a 18" long extension. Make your first cut about 2" longer then where the paint burns off & fine tune from there. Quite often with a 18" extension you'll find that its close enough without cutting them, but yours could be different.