3" exhaust? 2.5" exhaust...??

When I had the 340 in my street/strip Dart it had TTI headers and 2 1/2" exhaust with flowmaster 40's and turn downs at the rear axle there was a significant et drop by dropping the exhaust. I'm sure some of it was the weight but the exhaust wasn't that heavy.

When I built the 408 I went with Hedman's, 1 7/8" primaries and 3 1/2" collectors, 3" pipes and Pypes mufflers with turn downs at the rear end. The car would lose less than a tenth in the 1/8 with the exhaust, 6.57-60 with out to 6.66-68 with.

I have the same header/exhaust on the 434 and it's gone 6.44 @ 107.1 in street trim and made 543 hp on pump 93 on a chassis dyno. It's never been ran without the exhaust so I don't know what it'll do.