[78w72]

Originally Posted by 70KGOLD

Does anyone make a 2" roundport headers for a 1975 Trans Am? Dougs offer a set from 70 to 74. Only a 7/8 for 75 up.

As mentioned hooker super comp #4202 fit 70-81 Firebirds, they are listed as 70-74 due to the O-port shape but fit all 70-81 with O-port heads.

I have them on a 72 Firebird with an E-head 400 block stroker, fit great overall with no problems getting a full size pontiac oil filter in/out.... only complaint is that they do hang down lower than most other headers due to the big tubes & collectors.

[R 70 Judge]

Originally Posted by 78w72

As mentioned hooker super comp #4202 fit 70-81 Firebirds, they are listed as 70-74 due to the O-port shape but fit all 70-81 with O-port heads.

I have them on a 72 Firebird with an E-head 400 block stroker, fit great overall with no problems getting a full size pontiac oil filter in/out.... only complaint is that they do hang down lower than most other headers due to the big tubes & collectors.

I wish mine looked that nice!

I have Hooker 4202’s on my 70 TA with Flowmaster 4-2-1 collectors. They seem to work well and they give the car a very unique sound. I don’t think Flowmaster makes them any longer. The set on my car are 2” primary. I have a NOS set of Flownaster 4-2-1 in 2 1/8” that I bought new years in my garage. I planned on using them for a previous build and never got around to it.

[Steve C.]

http://www.wallaceracing.com/header_length.php

A tid bit. Some calculators, formulas and performance recommendations use the tube's INSIDE diameter. If that's the case you would need to subtract twice the tube's wall thickness from the outer diameter.
If so that header material might be 16 gauge (.062") or 18 gauge (.049").


One example here: https://www.discountmags.com/magazin...is-issue/12912

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