Header experts - real quick question

[pbs911]

never mind I'm an idiot sometimes. Unless Bill V's page is wrong I know the answer.

[Jack Olsen]

I'm no expert, but I've always heard that 1 3/4 ID is best for a more-or-less stock 3.6, and that 1 7/8 ID provides a greater benefit for modified race motors.

[pbs911]

Jack, that's exactly what I thought. I found conflicting reports. But here is a quote from Bill V's site.

Originally I tried to retain the SSI headers from the 3 liter, but I found that the primary tube (1 1/2" 38mm OD 1 3/8" 35mm ID) was far too restrictive for good power at the top of the rev range. Subsequently B&B ss headers(w/heat) were installed(1 3/4" 44.5mm OD, 1 5/8" 41.28mm ID primary tube), the engine is now properly responsive at all rpm.

BTW, any progress reports on BBII?