[mpmsmuscle]

What are the best d-port headers to use with Kauffman D-Port heads 315 CFM. Application is a 69 Pontiac Gto with a 474 stroker, m/t with 600 plus hp. I was trying to find d-port headers with 2 inch tubes. I am running a 3 inch exhaust with Flowmaster Delta Flow 40 series mufflers.

[grandville455]

600hp U would actually be ok with 1.75" headers, if u go to hedman hustlers they use adapter flanges for the 1 /7/8 and 2" , you certainly don't need 2"

[XLR8STEVE]

I had a Kauffman built 462 with 310 D port heads. 70 gto. Dougs D590 1.75" primaries. New motor, upgraded to 2" a whole different ball game. Way easier to fit the 1.75s.

[Half-Inch Stud]

Challenge: measure the "Best Header" against a header with the pusle-timing made MORE uniform between 5-7, 8-4, and
1--3 and 6--2.

Observe: 18436572
.........DS 1--3-57-1
..........PS -84-6--2
Dual exhaust being the stereotype that it is, the Dual exhaust format may still be okayee here.

I loath the notion of equalt tube-length headers being the best, and further loathe the "hot-bends" in primary tubes.

Car Headers with Equalazied pulse timing will allow all 8-CYLs to make the same CYL-HP vs rpm. This means equal-length Header do not have equalized CYL HP.

Therefore, start sketching, and yea it APPEARS to be a physical layout bummer for CYLs 1 &3, and CYLs 6&2. Maybe not, because perfect pulse timing is the enemy of better pulse timing.

As for my 68; bummer replacing my roundport headers with Iron manifolds due to ground-hit. DS done. PS awaits iron. Yet this does make an opportunity to implement a best header later on. Doesn't it.

[mpmsmuscle]

Thanks for the info. 😎