Hot Rods Building my entire exhaust system / Question

Make sure you size your system for the engine your using. Most tend to want to use too large a diameter pipe. Bigger is not always better when it comes to exhaust. Search, plenty of good articles. Not hard to do if your patient. 2x you can buy u and 90* bends from Jegs or Summit....mufflers and stright pipe from local shop.

 

Guess we are lucky around here. Have two real good muffler shops fairly close.

 

Not all muffler shops are equal.
But you can't expect quality work out if a hack no matter how much you pay them.
Most shops around here have squish benders.

 

my biggest pet peeve with muffler shops, is that they don't seem to understand that the axle moves up in the chassis, when you go over a bump in the road. They just will not make the U over the axle, tall enough.

 

One of the reasons I decided to do my own. My car sits pretty low already. Don't need the axle hitting pipes and wrecking them.

 

I recently built the Exhaust for my '35, and knowing that I was going to weld it I did not want Aluminized Pipe, so I bought my Pipe here:

http://www.mandrelbends.com/mandrel-bends.html

Prices were good, Shipping on time and they carry everything to build Exhausts, whether Steel, Aluminized Steel or Stainless (in about any Gauge you want it)-

I then had it Ceramic coated inside and out,and am very happy with the results-

 

Higher end stuff I always built my own out of tig welded stainless using mandrel U bends and straight pipe. I order the pieces pre polished then go back and touch up the polish at the welds if I want shiny, too much work to polish the whole thing. Had a friend with a muffler shop, did great work so he use to do all my mild steel tailpipes but unfortunately we lost him to a heart attack. Got another shop does OK but lately been doing all myself.
Your first one you might find challanging but once you get the hang of it it gets easier.

 

Any pictures of your bare rolling chassis with everything but the body in place ?

 

As far as H ans X pipes go, the debate will continue forever.
I can tell you that where the X pipe goes changes the tone, kinda like a trombone does.
If you study how sound waves work, when Identical frequencies on different waves collide they cancel each other out. Just from screwing around and trying things like building an exhaust system 40 different ways with a pile of mufflers. That was a fun experiment I'll likely never do again.

I can also tell you that perfectly symmetrical dual exhaust will drone like crazy at its resonance frequency. Non symmetrical can't establish a resonance frequency so there's no drone.

 

X and H pipes will usually lower the sound levels.....but hot rods are supposed to be loud!

 

I built mine on my Buick roadster out the back, including the headers. I bought the tubing locally, and had to make the head flanges. You can do it.

 

An X pipe does not reduce the exhaust noise it just changes the exhaust note.

Around here most of the real high zoot guys actually use what they call a Daytona Cross which is a pair of U bends (long radius) back to back. There is a science behind them actually making any more torque and placement will make a difference in where they develop the added torque. Some guys use the crayon stripe method to determine placement but there is an *actual formula that is exponentially more accurate. You want the crossover to be placed so that it develops more torque where the engine develops its torque and more often than not it is a dyno measurement and not a seat of the pants measurement.

*don't ask I don't know the formula that in itself is a @hotroddon question.

 

This cannot be emphasized enough, yet it is not.

There sure are a lot of pickup trucks where I live, with stock motors, sporting exhaust systems that can properly support ~740hp.

 

I don't have any "good" finished chassis pics with the exhaust in place but I have an early shot.
Also I agree with DdoubleD and gympyshotrods on the size of the tubing, on a street driven car velocity is better with smaller pipe.

 

I did the exhaust for my RPU using Porter mufflers and 2 1/2 " pipe. That's small enough for me and it will sound nice with the Y Block

 

I'm using 2 1/4" all the way to the axle and going down to 2" for over the axle and tailpipes. Why? It's what I have available.

 

I use bare steel tube and u-bends, tig welded and high temp coated.

 

Made my own by cutting up 180 degree 2.25" U-bends. It's not difficult just time consuming. Plan the route starting at the engine and work your way back. Tack entire system before final welding. ATTACH]

 

lots of very nice exhausts..... I for some reason wanted to use wrinkle bent tubing. all shipped from rock auto, cut up and pieced together.

 

This is a great thread. I just started building my own exhaust on my roadster today. Bought some bends from Summit and off we go.
I'm doing my own because I have more control over how, why and where. Actually have a pretty good shop down the road and at the time I didn't have my garage built so he did my 63 with very good results but the roadster is my retirement project.
I read in someone's post " its a lot of work". Maybe I'm abnormal but to me building this car is therapy. I cant imagine what I would do if I couldn't play with cars or be in my garage so the more I can do the better. I may not build show cars but most people seem to like my work. Guess I'm just carrying on the tradition of all those Hot Rodders who have gone before me. Thanks Guys

 

Seems like most guys with normally aspirated sub 400 CID engines think dual 3" exhaust is best.

 

Speedway sells a mild steel kit, don't think its coated. The cost difference between HPC coating mild steel, vs stainless material cost is about a push. But, you need a TIG

 

Just me, but I've been happy having a local muffler shop here in Kalamazoo do mine. Big cars, complicated, tucking through X members and so on. I don't have a lift, I'm not that clever, and I've never paid more than $350 for a complete system, with mufflers and tips, front to rear. That said, a buddy of mine here goes to Lowes and buys 2" conduit and builds his own, so, maybe I'm just lazy...;-)

 

Lot's of good conversation here about should or shouldn't you do it and clearly have some talented pipe fitters in the crowd. For the guy that wants to do his own but hasn't yet can we, the ones that have give them a little coaching on getting good round cuts in the middle of bends? I seen it mentioned a few posts back to use a disc sander. To me, that's Taboo. But then how do "YOU" do it? Maybe this is for another post. If so I'd be glad to start it.
The Wizzard

 

I built the exhaust for my 55 F100 using an exhaust kit from Speedway. I checked with a local muffler shop on my system and they quoted me $100 each just for the stainless flex joints, so I decided to build it myself. I don't have a lift and it was quite a bit of work for a guy in his mid 60's crawling back and forth under the truck fitting the pipe. My exhaust exits through the running boards, so I didn't have to pass over the axle.





As for cutting the pipe, I used a lot of masking tape setting up my cut lines. I made my cuts using a 4 1/2 " grinder with a cut off disc.

I did a layout on poster board to match the radius of my bends.



I used tape mark where I needed my cuts to occur.



Once I had my cuts made I would join the pipes together by tightly wrapping masking tape around the joint and cut away a small section to give access for my spot welds.


The use of masking tape may seem mickey mouse, but it held the joints tightly together for spot welds. As far as the X pipe, don't know if it does anything noticeable as far as power, but it definitely has a different sound at upper rpm for a sbc.



This may be totally useless information.......... just my approach.

 

Something I made to help keep the cuts on a true radius line. Also lets you keep track of the number of degrees in case you have to make ab 'S' bend with the legs parallel.
As you can see, the large radius bend locates on the outside of the fixture. The small one is located by the inner block. The intermediate one requires shimming from the sides to keep it centered.
The degree wheel is centered and has a pin to locate it radially (clocked).

This one is dedicated to 2 1/4" pipe. Would't be too hard to make one for multiple sizes.

 

There's a really good tech week entry from OUR last tech week on cutting bends. There's a few others too.

 

I just saw a truck today with a SBC 400, and dual 3-1/2" exhaust. I asked the guy how close to 935 horsepower he was, he said it was stock. Heaven help him when it is time for a smog check.

 

conduit for exhaust? fun.... I hope he's careful when welding it, the zinc fumes are not good for you. And it's an oddball size.

I just cut the tubing off with either my chop saw or a hacksaw, and wiggle and grind until it fits. The degree wheel, etc are neat ideas.

 

Pretty useful info here. Bump for any other ideas.