Howdy

I’m building a 400/512 for the street to go in a 54 dodge pickup on a heavily modified 2wd dakota chassis. I’m shooting for low buck and fun so part of the fun is scrounging and road tripping for cheap or cool parts.

A little back story and info:

I decided to go with headers not manifolds- got some crusty NOS no name long tubes 1 7/8” I think with short 3” collectors. Unported stealths, .507/.510 cam 240°/246° @ .050, rpm intake, 750 holley, mild built 727, 2500 stall, 3.21 gear.

I was always kind of against flowmasters because not only do they never score well in dyno tests I’ve seen but every jerk in a stock f-150 around me has that sound. I always get caught looking thinking a fast car is coming then it’s just a loud truck. I know sound is super subjective but for this build I actually want that deep hollow burbling idle and a loud wot too. I don’t care too much about giving up some power or off idle torque since the second half of my gas pedal will probably feel like driving on wet leaves anyway with 500+ tq in a 3000lb front heavy pickup.

So I got a complete 3.5” used but clean welded exhaust system with a 3” H pipe and flowmasters. I think they’re 40 series? The headers have short 3” collectors I am planning to neck up to 3.5 right after them then just put downspouts in front of the axle after the muffs.

I’m thinking it should be on the loud side but hopefully a little tamer than open headers or purple hornies or something. A little drone is ok it’s not a commuter car. I’m wondering if the huge system on the mild big motor will negate the famous power robbing reputation of the flowmasters? Luckily packaging isn’t a problem in a full frame pickup truck with running boards.

Does anybody have stories to tell about the flowmaster 3.5” mufflers? 3.5” exhaust in general? Am I going to kill a ton of torque? Wake the dead? I know I won’t have the over 600hp that would call for this exhaust and bigger headers too but it was $80 delivered and cartoonishly large I couldn’t help myself!

Radar