[BMFH]

Hello All

Will the Long Branch Manifolds fit a 70 Firebird 400 Engine/Frame?

Everything I have seen says up to 69.

Can anyone give me any information as to will they fit or not, if so are there any modifications that need to be made?

Thanks in Advance

Dusty

[A Schab]

No,they won't fit any F body after 69.

[rexs73gto]

No they don't but they fit real nice on the A&G body , & work very good on them . They look really good to.

[BMFH]

Hello All

The 70 Firebird subframe is about the same as the 67-69 subframes except it has front steer, correct me if I am missing something on this.

What are the problems encountered with using the long branch manifolds and the 70 Subframe? can it be worked out or around so that they can be used??

Forgive my ignorance on the subject, I am sure there are allot of you that know all about this subject, and I would value your input on this.

Thanks in Advance on this subject.

Dusty

[b-man]

Dusty,

The interference point is mainly at the engine crossmember, and likely the inside of the frame rails as well.

The long-branch manifolds won't fit an A-body chassis either, it needs the same mods to the front crossmember (heavy notching involving cutting, welding and hammering).

If the long-branch manifolds were a slam-dunk into the A-body and '70-'81 F-body cars then it's likely anyone looking for the best performance would be using them instead of the short-runner style Ram Air manifolds. The long-branch manifolds are superior to the other Ram Air manifolds, probably worth 10 to 15 HP over the short runner RA manifolds on near stock builds and even more on hotter engine builds.

I'm not saying you can't make them work, just far from a bolt-in operation.

Bart

Related thread with links to other related threads:http://forums.maxperformanceinc.com/...ht=long-branch

[Half-Inch Stud]

oh, i've got the Long Branch to fit the 68 GTO A body, but i' d be misleading on easy or practical. engine needs lifted 1/2 to 1" with mount bracket spacers, grind manifold and frane cradle.

A promising opportunity exists to re-cut the Manifold's head flange ever-so off-proper to hike-up-&-in the manifold's branch away from the cradle. nearly an impossible cut to predict. add to that taking little off CYL1,2, Take more off CYL, 7,8. so, a skew flat-cut would be specified. I never did such cuts in the flanges, yet that would provide relief.
That said, it takes bravery, determination, foolishness, lot's of floor jack tweaks on engine position, HEI to firewall concerns, sterring lockout rod to head concerns, and just plain narrow-sightedness to install Long Branch into the A-body.

When done successfully, the engine can shake at idle, or lean under load and not knock the frame. when done unsuccessfully, they make the bird-call ( or dog whistle) sounds of rod-knock. HIS