Frame rail as exhaust?

[justsomeguy]

So, it's pretty tight under the cab of my truck. I think the open headers will be a bit loud with a 7k RPM 383 SBC yellin in my face. I'm not willing to sacrifice exhaust flow for street manners, so baffles are out.

What about using the 2x4 frame rails under the cab as exhaust pipes to put the noise behind me? Anyone ever seen this?

 

[Sniper]

The only thing even remotely close that I'm aware of is the exhaust directed through the hollow dump box frame work of a dump truck. The idea there is to keep some heat in the load so it won't freeze to the box before it gets to the site. After a few years they would have problems with the frame work rusting and rotting out prematurely from the moisture in the exhaust.

 

[Snake Farm]

After a few years they would have problems with the frame work rusting and rotting out prematurely from the moisture in the exhaust.

That's the problem I would see......heating up and cooling down would sweat and cause rust problems. It sure would be cool though

 

[justsomeguy]

I wonder about coating the inside of the rail before welding it up to help prevent corrosion?

 

[Sam_Fear]

I'm thinking it is a impossible battle to win. You either couldn't have ANY corrosion or you would need to use double thickness tube for enough sacrificial material. 1/4" 2x3 stainless would last a long time - huh...I wonder how much that would cost?

....just my uneducated thoughts.

 

[skull]

roadster headers

can ya run roadster headers out and down the outside of the frame with mufflers.

that is how l solved my ride hieght problem on the 33 dodge sedan.

Later

 

[sneakysnake]

Could always make your frame from stainless.

 

[Bonehead]

You could use a powdercoat for the inside of the frame, or even a ceremic coat. but still no idea how long it would last.

 

[bob w]

Stick a couple 1 7/8" aluminized straight exhaust pipes inside each frame rail. Instead of using 2" by 4" rectangular tubing, have a fab shop bend 2" by 4" C-Channel, put the exhaust pipe inside and then box it.

Just an idea.

 

[zzrodder]

Stick a couple 1 7/8" aluminized straight exhaust pipes inside each frame rail. Instead of using 2" by 4" rectangular tubing, have a fab shop bend 2" by 4" C-Channel, put the exhaust pipe inside and then box it.

Just an idea.

Bob is a genius!! Best idea so far... What nobody has mentioned yet is the heat, this could re-define the term ' hot ride ' . Unless you live in Alaska, it could be hard to live with a roasting frame under your butt........

 

[RoddingRon]

Could always make your frame from stainless.

As soon as I saw this comment, I thought of this car...its got a stainless frame. The owner said there were only three or 4 sets of the rails made...I wonder why

 

[earthman]

Yep heat will be an issue.The heavy frame metal will heat up and stay hot.

 

[rainman]

I think the heat could be isolated!! You would have to leave some room between body and frame rails!!

 

[skull]

lizard skin

coat the top & bottom of the floor, frame rails and any where else ya think it might get hot with lizard skin or something along those product lines.

Later

 

[wendle]

Interesting.

I always run the coolant through the frame rails on my rock buggies. Generally from the engine back to the radiator on the passenger side, then forward to the engine on the drivers side.

Exhaust is a different thing though. I would think the heat to be more of an issue than corrosion. As long as it is always allowed to run long enough to dry out any moisture inside the rails a 2x4x0.125 would more than likely outlast anyone reading this.

The heat problem is interesting. Kind of hard to know if a rubber body mount or transmission mount is going to soak up enough heat out of the frame to break down? What about attaching brake and fuel lines to the frame? If you can do just one rail and keep the other one "cold" it might be feasible?

I'd try it!

 

[Sam_Fear]

Keep in mind ANY corrosion weakens the frame. It may last a long time as an exhaust pipe, but it would be compromised as a critical load bearing structure.

 

[pistolpete]

If you can do just one rail and keep the other one "cold" it might be feasible

Wouldnt there be a difference in expansion between the two rails. Slightly flexing the crossmembers over many hot/cold cycles and possibly tweaking the frame over time.

 

[Old Iron]

I'd kinda like to see it done

Jim

 

[ratrodney]

I think it could be done. Rail buggies n V8 trikes do it all the time. Coat the inside of frame rails with heat resistance paint then coat the exhuast pipes themselves. I think it would be kool and give you no issues. RR

 

[rainman]

The more I think about it, the more I think it could be done relatively safely!!
I'm not convinced moisture would be that big of a deal. But if I tried it I definately would try and coat the inside with whatever I could find that was the very best known!! About every two feet or so you could drill very small holes in the bottom to release any moisture that might build up!! Just a thought! Let us know if you try it!!