New exhaust questions

[White Lincoln]

I got my resontators in last night. I have a few questions about how to weld them and how to stretch the CAT exhaust pipes.
1. The current CAT pipes come together at the Y pipe they came with, but are too close together to fit 2 resonators.
a. Do I cut off the exhaust mounts to the tranny and weld them back on to widen the CAT pipes?



b. Do I heat and bend them out more so the ends of the exhaust are farther apart?
2. When connecting the CAT exhaust or Y pipe to the resonators:
a. Do I use a 2.25" x 3" sleeve to weld the pipes together?



b. Weld the exhaust pipe and resonator together?



c. Cut slits in resonator and expand the resonator pipe so the CAT exhaust slides into the resonator then weld?

Thanks!

 

[KevinVarnes]

That is the beauty of having a welder and various cutting implements. I would probably just butt weld the glass packs to the Y merge.

For the downtubes, I don't know if you are going to be able to bend them very well. You could cut them on the angled portion of the tube and shorten them there to get the width you need. You may have to weld extensions onto the tips then to reach back to where they originally were. Hangers you will probably have to do last once you get everything else sorted.

 

[White Lincoln]

Thank you Kevin for the input, it is much appreciated.

I did fail to mention that the CAT pipe is smaller than the resonators, so the resonators slide right over them and won't be a problem to weld the resonator and exhaust.

As for the hangers, that is a good idea. Wait till everything is together and and deal with those last. Hopefully, I get this wrapped up this weekend.

 

[Zep5.0]

Could you stagger the resonators one 10" back from the other? That would gain you an inch or two

 

[White Lincoln]

I pulled the CATs off, cut off the hangers and put them back up (loosly). I put the resonators on the CAT's and can move them out about 1" each to gain the access I need. I got the resonators welded to the Y pipe, I just need to put the coupling on the Y pipe so it can mount to the exhaust.

Tomorrow I should be able to cut the excess off the CAT ends and weld the resonator / y pipe to the cats and mount. Then tack on the hangers to hold them in place.

Of course RockAuto sent me mismatched resonators. Looks like Cherry Bomb was having some issues that day...

 

[White Lincoln]

Oh, I forgot to mention I cut slits in the Y pipe to resonator ends, hammerd the slit areas in a bit, then pounded the resonators onto the Y pipe ends. While welding, I had to fill some holes from the slits. I cut out some slits of pipe from scrap I have and used that to fill the holes. It turned out okay and the large blobs in the weld are the holes i filled. I am getting better at seeing what I am welding and making a nice flat weld bead on the seam of the joint. I know the pic does not show it well, but its better than when I first started.

 

[White Lincoln]

I got most of the work done today and I am down to the last two welds of the resonators to the CAT's. There is quite a gap between the 1 7/8" id of the resonators and the 1.5" of the CAT's.

I made a hole in one of the CAT pipes while removing the hanger, but patched that up today.





I also got the coupling from the old Y pipe cut and welded onto the new Y pipe.



Got a coupon from Harbor Freight for 15% of anything. I bougth some .35 gauge Flux Core wire (they were out of the .30 and half off sale I did not know about) and also bought a welders apron with a clip on rod handler and gloves. I wanted to get several other items, but they were wiped out. I guess last weeks mid-west storm delayed shipment.

Anyway, two welds left, as mentioned, the CAT's to the resonators. I will have to cut slits in both and expand the CAT and compress the resonator. I also need to cut back on the pipe for both. I already took 2" off the CATs pipe and that did not help. Another 1" for both should get me in the size I need so there is no pulling or pushing the parts to get everthing to fit.



Anyway, that is where I am at with this Cougar project.

 

[Zep5.0]

Not sure how close those resonators are, but if within 1/4", I'd be tempted to weld in a piece to hold them apart so they never rattle.

 

[White Lincoln]

Not sure how close those resonators are, but if within 1/4", I'd be tempted to weld in a piece to hold them apart so they never rattle.

Thanks Zep. I did ask about that earlier. I think the width is 1/2". Let me go check.

Update: Good eye Zep, they are 1/4" apart. But they are so short and the Y pipe weld is very stout so I would be suprised if there was any rattle from the resonators.

 

[White Lincoln]

For the downtubes, I don't know if you are going to be able to bend them very well. You could cut them on the angled portion of the tube and shorten them there to get the width you need.

I did consider cutting an inch or so out of the pre-resonator pipe (see pic, red square area) to shorten the pipe and widen the space of the CAT's. That still may be a better way to seat the CAT exhaust to the header rather than having them seated crocked in the header (the don't bolt up as well).

 

[KevinVarnes]

Just my opinion, but I would install the down tubes onto the manifolds and get them straight/in position and then fit everything to them from there. I know it isn't as nice as laying everything out on a workbench, but I think the end product will be nicer to work with. I have a Magnaflow Y-pipe on the '97 and it did not fit well onto the manifolds at all. It took a lot of force to get the pipes to bolt onto the manifolds with the hangers engaged at the transmission crossmember. I ram-rodded it into place regardless. A few months later one of those hangers broke off. The other one broke off several months later. I hate exhaust work as it is. Improperly fitting exhaust is just that much worse.

 

[White Lincoln]

Just my opinion, but I would install the down tubes onto the manifolds and get them straight/in position and then fit everything to them from there. I know it isn't as nice as laying everything out on a workbench, but I think the end product will be nicer to work with. I have a Magnaflow Y-pipe on the '97 and it did not fit well onto the manifolds at all. It took a lot of force to get the pipes to bolt onto the manifolds with the hangers engaged at the transmission crossmember. I ram-rodded it into place regardless. A few months later one of those hangers broke off. The other one broke off several months later. I hate exhaust work as it is. Improperly fitting exhaust is just that much worse.

Well said and your experience with these issues enspires me to do better. Now, with that said, the original position of the down tubes was about an inch in too much for the resonators at their current width. And as I recall, when I put it all together last night under the car, that 1" of difference made all the world of difference with how the CAT exhaust mounts to the manifold.

Maybe I should ask Grog if he could figure out how much I should cut off of the CAT back exhaust at the squared out locations in the pic above to make the ends widen out to meet the resonators correctly.

My whole reason for doing this was because the bass-acwards way I had this exhaust setup. The wife noticed right away the car had no resonator, and the mufflers never fit right. So now she gets a resonator and I get my exhaust done right.

 

[White Lincoln]

Update:
I layed the old Y pipe over the current exhaust and I think I can leave everything the way it is except cut an 1" off the resonators and CAT pipes.

The pic below is the old Y pipe exactly on top of the resonators. You can see the distance is not much between what I need and what I had.



This pic is the old Y pipe up against the resonators. That is how much I opened up the distance between the CAT pipes. I really don't think its that much to worry about. I don;t know how much Kevin had when he added a new Y pipe, will wait to see if his was the same or larger. That would help.

 

[White Lincoln]

Update:
It's all done. The pipes are all welded and mounted, including the mufflers. I took it for a test drive (it was like 35 deg outside) and the cars rattles are almost gone. i have a few left, not too noticable, but I think I know where they are and will get to those when it warms up outside.

Thank you to everyones suggetions and assistance with this project.

Here's a pic of my cat back exhaust (excuse the crappy welding):



I don't have a pic of the exhaust, but it is all welded and in place correctly,



And proper flange bolts with springs (I did tighten them some more after this pic):

 

[Rodeo Joe]

How does it sound?

Joe

 

[Grog6]

If you ever need calcs done, add a 12" ruler to the pic, and I'll help. Worst thing about my stroke was losing math for awhile.

 

[Kenz]

Looks good! What engine is in your Cougar? I see it says 3.8 but not sure if it a supercharged

 

[White Lincoln]

How does it sound?

Joe

Hi Joe, honestly, it sounds about the same with a deeper rumble, not as loud, but I did not drive it that much. I was listening more for exhaust leaks. I will let you know after I drive it on the freeway to see if I notice a diff.

One reason for the resonators is because the wife did NOT like the sound of Y pipe and OEM mufflers. The OEM resonator was huge and really cut down the sound. Another reason was the rattles from having a mounted exhaust instead of welded exhaust.

 

[White Lincoln]

If you ever need calcs done, add a 12" ruler to the pic, and I'll help. Worst thing about my stroke was losing math for awhile.

I'll hold you to that Grog!

 

[White Lincoln]

Looks good! What engine is in your Cougar? I see it says 3.8 but not sure if it a supercharged

Hi Kenz, it's the 3.8l "leaks like a sieve" engine. It would be nice to have a supercharger or even turbo charged, but has its own hassles too.

 

[White Lincoln]

One thing I meant to ask, do I NEED the CAT forward hangers? The one's that mount to the tranny brace? After installing the exhaust for the last time, I questioned needing the hangers because the exhaust is so stiff now, it is not moving anywhere, anytime soon.

Thoughts?

 

[KevinVarnes]

I think they are nice to have to keep stress off of the joints. The next hanger after the manifolds is way back behind the gas tank isn't it?

 

[Kenz]

The next hanger after the manifolds is way back behind the gas tank isn't it?

One at each muffler and another near location where stock exhaust splits.

 

[White Lincoln]

I think they are nice to have to keep stress off of the joints. The next hanger after the manifolds is way back behind the gas tank isn't it?

Next hanger from the tranny is the hanger at the differential.

 

[XR7-4.6]

With the ball & socket flanges at the manifolds and resonators a strong enough bump or dip may cause the exhaust to sag in the middle without those hangers. I don’t have them on my current exhaust which is from a New Edge mustang but the difference is that exhaust mounts rigidly to the right exhaust manifold which supports the pipes on its own. When I build my new exhaust with the headers I’ll be using those hangers again