Colorado V8 / H3 V8 header compatibility

[ReconH3]

Anyone know if headers for a 5.3 Colorado are compatible with an H3 Alpha? Doug Thorley has just started making some, and I'm seriously contemplating a set. Had a set in my TJ after the cast ones cracked. Want to do the same in the H3 before they go.


"Ex Umbris Venimus"

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[TrailBreaker]

According to my Electronic GM catalog, the H3 Alpha and Colorado V8 exhaust manifolds are the same part number.

 

[ReconH3]

According to my Electronic GM catalog, the H3 Alpha and Colorado V8 exhaust manifolds are the same part number.

Awesome!! Thanks for the great info. Just out of curiosity, and for inquiring minds, has anyone actually tried a Colorado header on their H3?

 

[TrailBreaker]

Dont know why any one would, since it is the same part, there would be no differance, therefore no benefit.

 

[ReconH3]

I actually meant an aftermarket header. Some manufacturers don't say they make it for both models. Doug Thorley is one example.


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[TrailBreaker]

LOL, Gotchya. The part numbers are the same for both trucks, so as long as they bolt to the factory pipes after the manifold, I dont see where it would be an issue.

I ran into the same thing when researching seats for my 3T. Most companies offer tracks for a Colorado/Canyon but not the H3, but they are the same tracks so the seats would work.

 

[ReconH3]

That's also a great piece of info. You should start a sticky for this section of compatible parts.


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[Hunner]

Sounds like they would bolt up to the head but I wonder if as they go down if there is a difference in the frames that could interfere. Don't know if this would show that or not. Might have to call Thorely and see what they say and about the 02 sensor location.
I have noticed they do not indicate by color that front cross member added to the H3? Just some points I thought of back when I was looking at them for the I-5. Still might apply to the Alpha 5.3.

 

[TrailBreaker]

Hunner,

i dont think it would matter, as long as they bolted to the stock tubes. If the header is the same on both trucks, then at least where they mate to the pipe would be the same, then it wouldnt matter what truck it was used on. Now if he was to do a new cat or soemthing along those lines, then it might be an issue. But just headers should work ok.

 

[ReconH3]

Hunner,

i dont think it would matter, as long as they bolted to the stock tubes. If the header is the same on both trucks, then at least where they mate to the pipe would be the same, then it wouldnt matter what truck it was used on. Now if he was to do a new cat or soemthing along those lines, then it might be an issue. But just headers should work ok.

X2 Otherwise they wouldn't have the same part number.


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[ReconH3]

I was just informed by the Colorado owner that the exhaust was deigned for a 2WD Colorado. He says there may be issues with the torsion bars hitting. He said it was a simple fix. Just thought I'd let everyone know.

 

[Doc Olds]

FYI, the OEM exhaust manifold part numbers matching does not mean that aftermarket headers made for a different vehicle with the same LH8 blocks will fit (ie. the header is not patterned on the OEM exhaust manifold, it is proto'ed to link from the head to the exhaust pipe flange based upon the space provided by vehicle used for the proto). Fenders and liners are different between 4WD 355s and 345s, and the suspension is substantially different when comparing a 345 to a 355 2WD.

That is not to say it is impossible that the aftermarket header fits both vehicles with identical OEM exhaust manifolds, just not a safe assumption.

 

[05Mudiak]

:nothin: just wana sub:thumbs:

 

[Scarsman]

I would also agree with Doc. I would not count on the headers joining back up to the pipe under the truck in same spot. Even if the stock exhaust manifolds are the same part, headers are a much different animal. A lot f things to route around on the way down.

Someone get a set and try it out! :corn:

 

[Mr_Rich]

I surf the Colorado boards from time to time to see what mods could be compatible. One of the bolt-in interior upgrades was installing Hummer H3 seats in a Colorado pickup. I look at the H3/H3T as a much more robust and strengthened Colorado-sized vehicle. I wouldn't want a Colorado because I felt GM just went too cheap on a lot of the body and interior parts.

 

[amrg]

Bumping an old thread.

Does anyone know if something materialized for the Alpha?