Exhaust pipe expanding

Rat Rods Rule

Help Support Rat Rods Rule:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

offroadrolls

Well-known member
Joined
Mar 20, 2012
Messages
1,343
Location
North side of Deer Mountain
Does anyone have a trick for expanding steel exhaust pipe? I've never been a fan of those expanding tools with all the fingers held together with o-rings. I do have a couple though......just don't like em'.
 
If you had a good tool, they work ok. I bought a Harbor Freight close out tool, it didn’t make it through expanding one use on a piece of 2.25” exhaust pipe. I ended up butt cutting and welding.
 
I'd imagine if you put some heat to the pipe while using that expander it would work better. O-rings will cook but you'll get 1 shot and will have to replace the o-rings for the next
 
That's the bomb! I might have to get one of those. We ended up turning a 2 degree taper on a piece of 3.25" round stock. Then with the help of a BFH we were able to expand the 3" pipe enough to insert the other pipe about 3/8". Next, we welded it up. Turned out nice.

'
so , why do you want to have one inside the other if you`re gonna weld them any way?
 
I would think lubricating the tool before putting inside of the pipe would be effective and less damaging than applying heat.

As per the instruction sheet and what I read on the web, I greased the crap out of mine. It broke the cast expansion pieces when I put pressure on it.:eek: It might have worked on a piece of swing set pipe, but exhaust tubing was too much for it. Granted, it came from Harbor Freight, so it wasn’t exactly what I’d call high quality. There are good expanders on the market, but not for $25 like mine was.:(

The reason to weld it with only 3/8” overlap is that some people don’t weld as good as others. Easier to weld a lapped joint versus a butted one. I got lucky butt welding mine, it was thick enough I didn’t burn through ( much) :D.
 
If you want to do this one or 2 times in your life, I would grab an anvil / solid bar or whatever fits in the pipe and start hammering. Just stretch the tube wall gradually until the other one fits in.
 
If you want to do this one or 2 times in your life, I would grab an anvil / solid bar or whatever fits in the pipe and start hammering. Just stretch the tube wall gradually until the other one fits in.

That's essentially what we did but, without an anvil. Funny too, there's a bit of an anvil on the back of the vise and it didn't occur to me to use it.

'
so , why do you want to have one inside the other if you`re gonna weld them any way?

If I could TIG as good as the guy's on TV I would butt them together but, when you're just cobbling straights and elbows together the lap joint helps in getting all the sections aligned plus to me it just seems stronger.

To take this thread sideways a bit here's the story. This guy stops buy the shop with a 1965 4WD F250 that's sitting on a 1973 F250 Highboy Frame but still has the 352 under the hood...well used but cool just the same. Anyway, the 2.5" dual exhaust system is at least 30 years old and literally falling off the truck. He asks me if I can do an exhaust for him and I tell him the best I could do is cobble something together out of sections and elbows like I did on my Suzuki. I did my best to talk him out of it but around here there's just nobody doing custom exhaust work anymore. Even in Denver it's tough to find anyone. So we strike a deal on a 3" single exhaust without going over the rear axle. It turned out pretty good but gosh, it doesn't seem like it was that long ago a good muffler shop could've done twice the job for 1/3rd the money in 1/2 the time.

From this point I had to heat an bend the pipe to move the muffler away from the frame. Also, installed a couple hangers.
attachment.php
 

Attachments

  • IMG_9355.jpg
    IMG_9355.jpg
    123.3 KB · Views: 20
Not many muffler shops around here anymore either. With the better quality tubing, a lot of it stainless, cars don’t need new exhaust systems every few years anymore. My 94 Ranger and my 99 F150 are still using the factory pipes all these years later!

Another thing, not many V8 cars around, mostly pickups. And most of that stuff is cat back systems, you can buy a pre bent system for the popular models and bolt it on yourself cheaper than the muffler shops can bend you up on a lot of the time.
 
Not many muffler shops around here anymore either. With the better quality tubing, a lot of it stainless, cars don’t need new exhaust systems every few years anymore. My 94 Ranger and my 99 F150 are still using the factory pipes all these years later!

Another thing, not many V8 cars around, mostly pickups. And most of that stuff is cat back systems, you can buy a pre bent system for the popular models and bolt it on yourself cheaper than the muffler shops can bend you up on a lot of the time.

I think you hit the nail on the head there Bama. Sometimes I wonder if a guy could earn a living just doing jobs on vintage stuff that shops now days don't wanna mess with. I'd guess most guys that have vintage stuff, service it themselves.
 

Latest posts

Back
Top