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Old 09-20-2011, 02:18 PM   #1
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Las Vegas , Nevada
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Posts: 609
Smog Legal Headers- Q's

Below is pic of exhaust manifold, with air tubes, that is exactly what is on my 89/90 345LE, 454, carburetor, dual air pumps, dual exhaust.

I'm considering headers and have to keep it smog legal so I'm asking anyone that has exactly the same set-up will share their experience.

1. Which headers did you decide to go with and did your new headers come with a new air tube assembly as a kit?

2. Did you just eliminate the stock heat riser? (mine is factory, slides on the 3 studs at L manifold where it meets the L front pipe)

3. Can you still remove & re-install the starter motor without interference of header?

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Old 09-22-2011, 12:16 AM   #2
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1984 34.5' Airstream 345
Foothill Ranch , California
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Whilst I dont have the same setup as yours, I do have some experience with 454's and the smog stuff.
My 1987 454 powered Suburban is TBI, but similar, and I can tell you that you will never get the old AIR Injection Tubes out, so dont even try!
None of the After Market Headers will have them, but they are not super expensive... I got the pair from Rock Auto for less than $50.

Whatever Headers you decide on, if you can stretch to it I would get Ceramic Coated... the last forever and remove much more heat from the engine bay..

The obvious choice would be Banks, but weigh the cost of the whole kit at about $1900 against the headers alone at $800.
There is a used set of headers on Ebay from an '84.. he says they are SS, but I dont think so...

My '84 has the Banks Power kit on, and I can confirm that the sound is mellow, and the darn thing flies!

Next to consider, is Doug Thorley Headers... They come in around $700.

Check out Hedman, Hooker, Flowtech, JBA, and even Summit and Jegs, although not all of them do Smog Legal stuff.
The tricky bit is figuring out what will fit, as the is no direct parallel between Trucks, and Motorhomes, and emissions years... For example, My 87 Suburban has TBI, a single AIR injection Pump, and Cat, yet was made before your M/H!

My name is Steve.... and I am an Alumaholic!
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Old 09-22-2011, 05:28 AM   #3
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1994 30' Excella
alexandria , Kentucky
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I have a pair of Doug Thorley headers on a Jeep. They have a nice sound and the flange is thick where they bolt to the cylinder head. I would also get a set of REMFLEX exhaust header gaskets. You can torque the bolts and forget about them. If you buy cheap headers/gaskets you may find yourself retorquing bolts on a regular basis.
You will loose the heat riser but that's not the end of the world. It just helps the engine warm quicker for emissions.
Steve, Christy, Anna and Phoebe (Border Collie)
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2009 Dodge 2500, 6 Speed Auto, CTD, Quad Cab, Short Bed
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Old 09-22-2011, 10:01 AM   #4

2003 25' Classic
Zanadude Nebula , Milky Way
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Had a Banks Power-pac on our 95 454 Burb, put it on at 5k, 175k and no corrosion problems at all,(stainless). Quite a power boost and improved mpg by about 2.5 towing. Not towing, not so much....hard to keep 'yer foot out of it.

Can't comment on smog legal, NYS has no smog test requirement, but it never caused an SES emission light.

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Old 09-23-2011, 08:48 AM   #5
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1988 32.5' Airstream 325
Groveland , California
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Doug Thorley Headers

I'm in the process of installing a new 454 crate engine with Edelbrock EFI and a 4L80E transmission behind it. I have a set of Calif. CARB legal headers you can have if you want to pick them up in Turlock,CA. They have the air injection orafices, the starter is easily replaced with them in place. I found it necessary to wrap the tubes adjacent to the starter as well as a thermal planket for the starter motor itself.
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