Bonneville America Forums Forums Technical Forums Exhaust Reducer cone Diameters,,,one more time

My stock Speed Master pipes have a reducer cone inside diameter One Inch(1").

Does anyone with performance pipes know their I.D. (just after the header).

I'm going with FCR 39's, but want to keep the stock look.
I'm sure that the Reducer I.D. on Performance Pipes are larger than my stock pipes.
I can easily punch it out, just don't want to get greedy.

Thanks

If you already have the baffels out you NEED to leave the reducer for some back pressure.