Small block E-body headers fit in a B-body?

[rumblefish360]

Rumblefish,
Having gone from 1 5/8 primaries to 1 3/4 on a chevy 350, I know for a fact my TQ and HP went down, test was done on the same day and with 2 hrs of each other, nothing else on the car or engine changed.

A book on exhaust, air flow (Not on exhaust) and small pipe air flow is a good read worthy of your time.

Sorry to hear your 350 Chevy took a dump on ya.

On header pipe size, the bigger header tube is OK except on stock engines IMO, though I have not been there and done that.

The idea is not to let the exhaust gasses expand into a cloud inside the pipe but to keep it contained (Which also keeps it hot and it is trying to expand) to get it out quicker.

Hence the reason you do not put zoomie headers on stock 318's. Extreme and silly example given.

I have yet to go slower by the move from a 1-5/8 to a 1-3/4 tube size header.

Exhaust pipe size is also under the same idea. Proper sizing. Not overkill.