Classic motor home exhaust

[MoundCreek]

Good afternoon everyone, has anyone upgraded their exhaust recently to headers on the 454 Chev. Mine is a 1986 classic 34.5 and banks no longer makes a kit for that year. Any recommendations?

[Waipio Rim]

I replaced the stock exhaust manifolds on our 1990 345 with Doug Thorley headers two or three years ago, paid about $700 and had to wait four months for delivery. I have not learned to weld and paid a shop to install them. I had the option of getting headers with air injection tubes like the original manifolds had or deleting that whole system.

[MoundCreek]

Thank you for the reply, I assume like mine you have the smog system with the air tubes on your exhaust. Thorley has the standard headers without the tubes however could be a long wait for the tube version. Not sure if I should delete air injection tubes. Any thoughts on this?

[bkahler]

Originally Posted by MoundCreek

Good afternoon everyone, has anyone upgraded their exhaust recently to headers on the 454 Chev. Mine is a 1986 classic 34.5 and banks no longer makes a kit for that year. Any recommendations?

If you can't find headers, I believe I have a set of factory exhaust manifolds that came off an 86 345 sitting on the shelf.

Brad

[Waipio Rim]

Originally Posted by MoundCreek

Thank you for the reply, I assume like mine you have the smog system with the air tubes on your exhaust. Thorley has the standard headers without the tubes however could be a long wait for the tube version. Not sure if I should delete air injection tubes. Any thoughts on this?

It won’t pass smog anywhere without the tubes, but that whole setup reminds me of a blacksmith forge and could explain why the stock setup has a reputation of cracking and leaking.

But, if I was you I would grab Brad’s set while the offer stands…

[hairyclive]

Originally Posted by MoundCreek

Good afternoon everyone, has anyone upgraded their exhaust recently to headers on the 454 Chev. Mine is a 1986 classic 34.5 and banks no longer makes a kit for that year. Any recommendations?

some info here
https://www.rvforum.net/threads/head...r-home.117376/

guessing you are on a P30/40 chassis

try these
https://www.sfxperformance.com/parts/JBA1822S-2.htm

https://www.sfxperformance.com/parts/HED69570.htm

https://www.summitracing.com/search/...SAAEgLZT_D_BwE

you might find a old VGC or NOS set set on eBay, or a race parts/4x4/RV forum
or maybe even search the RV wreckers

you can have the AIR bungs welded onto any set of uncoated headers so find something that fits

you can also buy "make your own header kits" that work fairly well if you can weld

https://www.google.com/search?q=make...t=gws-wiz-serp

[dadstoy]

You want long tube headers (also known as full length headers). Follow what Banks did...

[LM782]

After a fair bit of research, I purchased and installed Hedman 69821 that have fittings for the air pump connection in 2021. (They are long tube headers.)

I initially placed an order with Doug Thorley (installed on The Onion 30+ years ago), but was told they could not give me an estimate on when the order would be completed.

[MoundCreek]

Thank you all for your responses. I know this thread has been talked about many times however today it seems to be difficult to get headers for these older airstream motorhomes. Thorley could not give an estimate for the smog version of the headers and of course banks dose not make them anymore for this application. I would like to keep the anti smog system as it could help with resale someday in states requiring this system. My motivation for headers is to increase performance and cooling. Thanks for all the help, Bill.