Header size
- Thread starter 85notch
- Start date
MentalMisfit
Club Member
Going to be tough without telling anyone what your combo is. Honestly i'd just ask whoever is doing the headers for your car. They usually have done enough to know what works.
1nine84GT
Forum Member
With out telling your combo I would suggest calling sumitt or jegs and ask them.
johnquick302
Club Member
if your spraying it, biggest you can get
DaryWilson
Club Member
they way ive always understood header sizes are as follows. maybe im wrong? maybe im right on the money but its how i look at it.
a mild motor should only need a header a size or two above its actual port size, example, a sbc exhaust ports is maybe 1 1/2 inch so a 1 3/4 header would be more then plenty for exhasut flow, then as far as power added cars the bigger the better beacuse what ever is crammed into that cylinder has to come out. correct?. step headers reduce reversion.which is caused by overlap on a big cam, which pollutes the fresh air charge in the cylinder with exhaust gases. so the bigger tube basically acts as a vacuum to keep a constant pull of the gasses out teh tube. so unless we/you know whts bein built its hard to say wha size tubes u need. hope it help
a mild motor should only need a header a size or two above its actual port size, example, a sbc exhaust ports is maybe 1 1/2 inch so a 1 3/4 header would be more then plenty for exhasut flow, then as far as power added cars the bigger the better beacuse what ever is crammed into that cylinder has to come out. correct?. step headers reduce reversion.which is caused by overlap on a big cam, which pollutes the fresh air charge in the cylinder with exhaust gases. so the bigger tube basically acts as a vacuum to keep a constant pull of the gasses out teh tube. so unless we/you know whts bein built its hard to say wha size tubes u need. hope it help
Last edited:
OldbutNew
Club Member
Some header fabricators have a program that takes several factors as inputs and spits out guidelines for primary size at the port and the length of each step. I have seen 3 even 4 different size tubes between the port and collector.
N/A at the port you can go as small as 1-5/8" all the way to 2" +. Power adders move you up a size or three and change the step lengths.
N/A at the port you can go as small as 1-5/8" all the way to 2" +. Power adders move you up a size or three and change the step lengths.