[79 Phoenix]

I have a 76 400 500557 block with 6X heads. The engine was originally out of a 76 A or B body car with 2bbl carb as near as I can tell from the code charts I have seen. Most recently the engine has been in a 71 Firebird. I can't find the exhaust manifold codes in any of the charts I have. Does anyone have a way to ID these manifolds? Thanks

The Right hand code is 9779328
The left hand code is 490143 4

[johnta1]

1965 - 9779328 - GTO Right

1969 - 490144 PN; cast # 490143 - 350/400 - FB LEFT STANDARD

['ol Pinion head]

The LH manifold code 490143 was not used as early as 1969. That casting manifold is a LH usage 6 bolt flange rear dump manifold, used beginning in late '72. As a very common casting number LH manifold, it was used in all '73-74-75, poss 76 Pontiac V8 chassis EXCEPT '73 & 74 Venturas. As it has 6 bolt holes to the head, it can be used on earlier heads.

The LH rear dump style manifold that preceded the 490143 was of the 4 bolt mtg style, it's number is 480602.

Hanging in the racks I have literally dozens of clean early '70's through mid 70's Dport exhaust manifolds. Have sold many fold more.

[79 Phoenix]

Thanks guys! I couldn't find any listing and had no idea what I have.

This engine came to the previous owner in a 71 Firebird he bought from Second Generation Engineering --a Firebird builder in north NJ. He decided then to put an LS in the Firebird and that's how I got the engine.

I am assuming the engine is pretty much stock based on what he told me. I have a partial list of what was done to the engine but no info on cam or any head work. Sounded good in the video and he said it runs strong. I'm guessing maybe a mild cam... So, I'm also guessing these manifolds are nothing real special but quite adequate for what I have...

[steve25]

Indeed, the 9779 prefix was first used in 1965, but the 490 code was first used in 73.

[79 Phoenix]

It does look like a "C163" date code on the manifold... Could that mean March 16, 1973?

[steve25]

Yup!