I have built a few sets for a different makes chevy, dodge ,amc ,,if you have a dragster or an altered taking advantage of the open space you have to make each tube equal lengths with the same angle bends on each tube that is the perfect header exhaust pulses getting to the collector with that perfect exhaust pulses ,,but in a door car stock engine bay you always try to get that that same result but in some designs I see the header builder try to get that equal length and some times has one or two tubes that extra bends or tube routes that reduce exhaust flow ,with other tubes taking a more direct route to the collector ,,one other area sometimes neglected are the primary header tubes welded the header flange can be somewhat desirable flow conditions ,,,its all about planning your best route ,,having built a few sets ,it is easier said than done ,,the only way to really know is bring a few sets to the dyno ,, different sizes and dragster header vs stocker header
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