SHO Source Y-Pipe Fittment-Tweaking

[myotis1134]

Ladies.

I currently have access to a nice big warm garage, so I'm trying to slam the rest of my y-pipe fitment issues before I'm working on my car out in the cold. And it's cold af in Alaska right now...

I'm getting the last piece of the y-pipe welded up tomorrow by a professional, so I'm not stressing (much) over those results, but the middle of the 180, on the rear to-manifold pipe contacts the transmission a little and I want it to not do that.



Before pulling the y-pipe tonight, I marked up the area of contact. I marked the approximate center line on the pipe (red), and figured out an area that would allow about 1/4 inch clearance (blue/green).



So my question for today is how to achieve that specific crush on that area without ******* the whole thing up?

The closest thing I've found to a tutorial on this particular subject was some random episode of engine masters (which was quite good actually - episode 4), and some halfass video on youtube - which I quit 30 seconds in because it looked more like some amateur blacksmith reality show than an automotive tutorial.

After thinking it over, my most reasonable-sounding plan consists of making a die out of wood or whatever to fit and support the opposite side of where the crush will be, then heating the contact area and using a bench vice to make the crush.

Alternatively, I could attempt to oval the immediate area - crush both sides equally with a die on each side. This method seems like it would be crazy complicated, and would cause a greater chance of ruining the overall fit.

Has anyone run into this problem before? I need advice - theoretical or hard-earned.

 

[yaycandy]

Yes the sho source pipe needs lots of tweeking. It was a pain slowly tightening and bending it out of the way. I think the shift area was close to the pipe also. Its do able just takes time. The pipe itself is good just the clamping areas and header area needs tweaked while tightening.
Ill ask my buddy to see what we did because i dont really remember but i know it was a pain to install on my 90

 

[yaycandy]

Only picture i have. I can go to the body shop its at and take more pics if needed. Clamp placement was a pain also

 

[zoomlater]

If the pipe is that close, is there enough space to remove the oil drain bolt. It supposed to close in that area, but you can install a shorter length bolt. It looks like that section of pipe is already welded. Did it clear when the test fit was done

 

[Irish Pride]

Mine comes down right next to the oil drain plug. Not close enough that it touches the oil pan but close enough that I needed to switch to a shorter plug.

I would look into all possible options before you start bashing the pipe in. Kind of counter productive to do that. I know it will fit without touching so something else can be done.

 

[yaycandy]

Mine is welded now also. Always get it clamped up good for a little bit. Then you can tack weld it at the seams to hold it to its shape. Then when removed it can be fully welded in the correct shape. I wouldnt say that every car is different but some fitment varies between cars.

 

[Irish Pride]

You might also look at other reasons it's not fitting correct. If you have bad mounts or worn mounts that will throw the fitment off. I have solid mounts in the front and rear.

 

[myotis1134]

The mounts are good - I inspected the **** out of them when I dropped the original y-pipe, and ended up replacing the studs, but the cup mounts were in good shape.

I replaced the oil drain bolt with one of these EZ valves some time ago, and it hangs out much further than the bolt-plug ever did, but it isn’t impeded in any way.



The front bend sits close to the frame in one spot but doesn’t contact anything - the rear bend is the only place where that is happening.

I know that I had clearance everywhere when I clamped it in place. Perhaps the welding tweaked the orientation a little.

Anyways, the rear 180 is the only spot that needs tweaking.

 

[Irish Pride]

I was referring to the engine mounts, not the subframe bushings.

If it's already welded then you don't have much option now. If you removed it from the car and then welded it, yeah, it probably tweaked itself.

 

[Old Stang]

Just thinking out loud here...
If all else is aligned and that area at the apex of the 180 is still a clearance issue, you could grind or plasma cut the oval area out and weld in a flat piece to maintain the clearance.
,,, I haven't had to deal with this particular issue, but I do have some DIY experience with taking a hammer to metal and it typically deforms in more areas than intended... less dramatic, but somewhat like trying to contain a water balloon with just your hands. My $0.02, food for thought.

 

[PaulTAutoX]

I think I saw the same Engine Masters. It goes on the basis that the total resistance to flow is a matter of all of the restriction through many feet of pipe, and losing even 10-20% cross section area over a very short length does not make that much difference to the total. (for compressible gas - liquids are different)
It is difficult to totally control the shape, but if you can pinch the sides where you are going to be banging on the top,
>0<----pinching with a vise
|^|
indenting here

then the circle won't change much, and you can just use a big ball pein or a much thicker segment of pipe across the axis of the pipe as the indenting tool. You have to reverse round the outer surface curve, you can't do this gently. You may end up with the section of exhaust pipe having a slight bend since you are shortening that side of the pipe. Cutting and welding will also put a little pull into that side but that's more dependent on workmanship.

 

[myotis1134]

@Irish Pride - Your engine mount comment has haunted me the whole week. Thanks for that... but if they are starting to give up the ghost, how can I fitness test them?

The engine rocks under throttle, but not a lot. I mean the things are only 30 years old and were only present for one catastrophic engine failure...

So pipe-crushing-while-preserving-bend-integrity procedure 1.0 was a slight success, but mostly failure. I think I'm on the right path though.

I locked it on the vice, and used a c-clamp with a section of 3 inch ABS on the "back side" to provide force.





In hindsight, it may have worked perfectly if I reversed the orientation and applied force directly onto the crush area.

So I applied fire from a bottle torch until red around the area, and gave it a turn. Give it a minute and repeat.

I placed the fixed jaw on the crush area, to place the most surface area on it. This turned out to be a mistake, as the amount of deformation I achieved was not impressive. Next time I'll flip it around with the movable jaw on the crush so torque can be applied directly.

I cut up a 3" ABS elbow to make a "bracket" that would contour to the 180 point of the crush, and drilled out a slot for the cup. The idea was again - surface area, and it actually worked pretty good except for catching on fire once.

I was thinking my next move would be to use a bench-vice, but the clamp may still work. It's a conundrum.

 

[yaycandy]

For anyone else, dont be afraid of this Y pipe from Sho Source. Its made very well, needs tweaked a bit when installing in pieces. Dont weld any Y pipes before test fitting, some you may get away with my most you wont on any car.