Custom Stainless Downpipe using RJC Flange

[liquidh8]

I have a hybrid Buick/Olds/Pontiac G Body wagon. I decided to build my own downpipe, ensuring there are no clearance issues or things banging/hitting. I had a used SS Magnaflow exhaust system from a friends 04 Chevy 2500 from a few years ago, nice thick pipe and a lot of bends to choose from. I bought the SS flange with the giant puck from RJC racing. The car has new body mounts and already had the seam where the floor and firewall meet. I have a build thread of the frame off on gbody.

My TIG welding is a little rusty, so be nice.

Starting with a bend on the flange




Test fit in place. Plenty of room for the AC box and the upper control arm. I will be using the stock control arm heat shield.


Nice and tight to the engine.





All welded up.


Wrapped in DEI titanium wrap. This is really nice stuff, and super easy to get real tight!








This leads to ceramic coated 3 inch exhaust. I just have to make the "test" pipe. I'll need a new flange and I will be using a SS flex joint in there. The exhaust hangers/mounts are SS with the little round poly bushings, so it is pretty solid. This is the reason I want to run the flex joint.

 

[wantattype2]

Nice Work !

 

[liquidh8]

Thanks! I was just going to use a stainless band clamp like i did with the mufflers, but, the intermediate pipe still moves around with the clamp torqed down. So, I will be welding 3 bolt stainless flanges to the downpipe and test pipe.

 

[turbo89]

Thanks! I was just going to use a stainless band clamp like i did with the mufflers, but, the intermediate pipe still moves around with the clamp torqed down. So, I will be welding 3 bolt stainless flanges to the downpipe and test pipe.

Ditch the downpipe wrap if that's 304 stainless

 

[liquidh8]

Ditch the downpipe wrap if that's 304 stainless

Out of curiosity why?

 

[turbo89]

Out of curiosity why?

IT promotes cracking from the inside out

 

[liquidh8]

I appreciate the insight. I don't remember what grade stainless it is, but is was free, and only took a few hours to fab a DP that has absolutely zero clearance issues. If it lasts for a few years, I build another using the same RJC flange.