[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.

[johnta1]

I wouldn't know why they wouldn't work in 75 and up?
If wanting pipes all the way back to rear it may be hard to do.
But if open headers, should work?

[PAUL K]

Hooker does, they advertise them as 70-74 due to the round port heads. I think the PN. is 4202

[Skip Fix]

As Paul said Hooker 4202. Fit my 78 and the 79 Camaro with the IA motor in it. And IA block needs a little massaging esp on #1 to clear the block and freeze plug area.. May need a dimple near the rear lower A arm bracket on the frame. Some sets near the oil filter. one set i had was real bad at the oil filter.

[steve25]

Why do you need 2" headers ?
To make good use of such and produce the highest average torque numbers your Exh ports would have to flow 225 cfm@ 28".

[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

.

[Skip Fix]

I had GP headers copy a set of the Hookers in SS!

[Skip Fix]

http://forums.maxperformanceinc.com/...ght=GP+headers
Mine

[R 70 Judge]

Originally Posted by Skip Fix

http://forums.maxperformanceinc.com/...ght=GP+headers
Mine

Wow! Those are super nice!

[70KGOLD]

Originally Posted by steve25

Why do you need 2" headers ?
To make good use of such and produce the highest average torque numbers your Exh ports would have to flow 225 cfm@ 28".

My heads flow a tad better than 225.

[Don 79 TA]

Dougs makes a 2" round port as well
i dont know if they make it any larger, as i thought there was another size as well
i have the 1 7/8 and they are nice, especially for bolt access and everything else

[Skip Fix]

The Hookers also clear the ignition key/trans locking rods!

[421 Bird]

I have a set of the Doug's 2" headers that fit on my 1981 Firebird with a 421 motor.

Joe

[grandville455]

Originally Posted by 421 Bird

I have a set of the Doug's 2" headers that fit on my 1981 Firebird with a 421 motor.

Joe

How’s the fit? Pics?Do they hang low like the hookers? They look identical to hookers 4202!

[421 Bird]

Originally Posted by grandville455

How’s the fit? Pics?Do they hang low like the hookers? They look identical to hookers 4202!

They actually fit pretty good. I did not have to make any modifications. I don't have any pics. The motor and car are sold. They didn't seem to hang low to me. I have not seen how low the Hookers are so I really can't compare them.

[grandville455]

Originally Posted by 421 Bird

They actually fit pretty good. I did not have to make any modifications. I don't have any pics. The motor and car are sold. They didn't seem to hang low to me. I have not seen how low the Hookers are so I really can't compare them.

These are hooker 4202, they hang below my canton pan

[421 Bird]

I don't remember them being that low, but I can't say for sure. I sold the motor a couple of years ago.