Spent a day welding exhaust - Pics

[IsaacHayes]

Yeah the orange care isn't a DD so no worries there. It's a toy, so it will be taken out on sunny weekends for some excitement. Race car thrills! Loud and nasty!

Did the exhaust valve ever burn up on that moped with no manifold on there? Not sure how 2-cycle "valves" take to that kind of thing but 4 stroke doesn't like that.

[Schmieder]

Might want to put a flange or some way of disconnecting the exhaust from the DP.

How big is your DP? 3" or 2.5" ?

My orange car will be loud as hell, cammed, high compression, then headers with no cat and a straight through muffler... hehe.

I have a 3-bolt flared joint just behind the cat and one in the engine bay. I replicated the OEM exhaust flanges so as you said, can seperate the dp from the exhaust.

DP is 2.5". The entire exhaust is 2.5" tip to tip. Except for the cross-over, they are 1.75" as stock are to bolt up to the stock mani's w/o issue.

I don't think I need a larger chamber as the turbo will put out a steady swirling exhaust versus the stock pulses w/o turbo.


Your orange car, hehe, loud is fun. Sounds like a bad ass exhaust system
But I have a family, kids, and live in a nice neighborhood. The neighbors would hate me leaving the house at 7am with a loud exhaust.

Reminds me when I was 15-16 yrs old and I had a paper route. I also had a red Honda moped with no exhaust, lmfao. It was exhausting right out of the exhaust port. Well, the exhaust came off days before christmas morning. My bike happened to have a flat that morning so I had to use the moped. Here I am at 4am christmas morning zipping through the neighborhood loud as all hell. My Mom said she could hear me blocks away. When I had to collect days later, nearly everyone complained about that. Too funny.

It was that same moped I had duck taped starting fluid canister to the body and directed the spray needle into my air intake. A press of the foot on the nozzle with a block of wood and it made a ghetto NOS. That moped would really wind up good. It actually worked quite well.

[IsaacHayes]

I was going to say as soon as I saw the outside of that "cat" that it was the siliconeintakes.com "fake cat". I will probably put one of those on my orange car. Since it won't be a DD and I might gain 2hp why not? LOL it's cheaper than another $90 cat and I can put my metallic core cat on my DD. Plus the orange car needs all the sound it can get, since it's a street rod... The orange car right now has 2.5" exhaust no cat and some muffler I don't know what kind but sounds damn good, better than my 3100!! My blue car has 2.5" mandrel stainless exhaust so they are going to get swapped between the two cars sometime.

I've had 201 stainless (your fake cat) welded with 304 rod, and 304 rod with unknown stainless sheet metal welded to normal steel. All done with TIG but shouldn't be an issue. Might want to put a flange or some way of disconnecting the exhaust from the DP.

How big is your DP? 3" or 2.5" ?

The exhaust should be pretty quiet with turbo, resonator, and flow master. The resonator should kill some of the high frequencies, the flow master some of the deeper ones, and turbo just make it quieter all around. You should be able to get on it without attracting much attention.

My orange car will be loud as hell, cammed, high compression, then headers with no cat and a straight through muffler... hehe.

[Superdave]

I've done it several times welding stainless tips on, you shouldn't have any problems.

[Schmieder]

please tell me that clamp for the "cat" is just temporary... you did the rest right, i don't see why you would want to cheap out there and potentially leak...

If mild steel welding wire will bond correctly to stainless steel, then yes it is temporary. But as far as I know, I can't weld aluminized steel to stainless steel.

And if the welding option is out, won't a carefully used red rtv seal up with a clamp?

Would you happen to know if stainless can weld to aluminized (basically mild steel with alum coating I can sand off)?

EDIT: I found out I can grind the edges well on the stainless and it should work out well. So, tomorrow I have some more welding to do.

[robertisaar]

please tell me that clamp for the "cat" is just temporary... you did the rest right, i don't see why you would want to cheap out there and potentially leak...

[Schmieder]

nice work!


make sure to wire brush those welds, use a scouring pad then paint thinner to degrease the whole system and give it a few coats of high temp exhaust paint. It'll last much longer that way.

You're right, I should do that to prevent rusting.

Notice I didn't care about dual exhaust. Seems trivial as it doesn't aid in flow really. If I had stock mufflers then I would but flowmaster 40's flow very well as is.

It will be loud, but not obscenely loud. The turbo will kill a lot of noise off the bat. The new resonator and flow masters will take care of the rest.

I am going to use a tip that points downward so the ground absorbs some of the higher frequencies and reflects the lower frequencies. The 2.5" exhaust will definately aid in exhaust sound quality.

[Superdave]

nice work!


make sure to wire brush those welds, use a scouring pad then paint thinner to degrease the whole system and give it a few coats of high temp exhaust paint. It'll last much longer that way.

[Schmieder]

Several hours today, not bad. From ripping it out to measuring, cutting, welding, leak tests and double checks.

Used a level and carpenters angle device.

Here is the entire exhaust under chassis w/o down pipe.


Here is the catalytic converter. I still need to weld in the O2 Sensor for emissions. Looks like it will pass visual inspections.


Here is the internals to the catalytic converter. The turbo will love this. It isn't just gutted, it's a clean pipe so there is no turbulant edges.


Here is a close up of my welding. Not bad for a gasless flux mig welder.


Tomorrow I will jack up the car, mark off my supports and weld them onto the exhaust pipe. I have raw 1" x 3/4" x 1/8" steel bar for the supports. Will be using rubber between the mounts and the chassis for no rattling.

Will also finish the downpipe if I have the time.

I hope you all enjoy the pics of my progress so far.