Magnaflow cat pipes and 96-98 vs 99-01 cat pipe differences?

[JoshT]

Yes, the thread changed. Was originally asking about collector exit size, but found other posts around the forum that confirmed what I thought I'd found in the past. TM headers use a 2.25" ball type collector. I've got OBX, but they SHOULD be the same since both are made to connect to stock pipes. Finding that answer created new questions, so why not revamp the thread to make more sense.


Getting full new exhaust put in my 99 Ranger V8 swap. I'm planning to go header back 2.5" with forward cats in place. Don't particularly care about rear cats since everything behind the transmission crossmember is going to be custom and they can be added back if I ever needed. In my searching for information I discovered the mandrel bent Magnaflow cat pipes.

Are the Magnaflow cat pipes actually 2.5" pipes behind the header extension?

I can't find any measurements listed online for the magnaflow pipes except for 2.25" inlet which matches the collector, but the pipes look like they step up behind the collector extension. Honestly even if they are only 2.25" they'll probably be flow good as the crush bent 2.5" I'll find at the local exhaust shop. I've seen the threads talking about the poor welding on them, but again I think it is as good as I'd find at the local exhaust shops, or atleast the ones I'm willing to pay for.

The guy that quoted a starting price of $1600 without cats is not getting my money, but with that number I don't think that he wanted it. He also tried to tell me that there isn't room for them without looking under the truck, and that I was already breaking federal emissions laws from just doing the swap. That's a story for another time, or never.

There seem to be two different cat pipe styles on the 5.0 Explorers, what I find onlines says 3 piece for the 96-98 and 2 piece for the 98-01. My 2000 donor had the 2 piece, but then my old 98 donor did too. Anyhow the two piece splits left and right bank with each side containing both cats in an assembly. The three piece has the left and right primaries separated, then the secondaries combined into a third piece. Not that y'all needed the explination, but it's leading somewhere.

2 piece setup is around 800 per side. Three piece I can find for 200 right, 500 left, and I wasn't planning to use the rear cats anyway. So about 1600 vs about 700. I think you know where this is leading.

Is the layout of the 96-98 cat pipes similar enough that it will fit on the 99-01 explorers without issue?

If I have to have an O2 bung relocated it isn't an issue since I need to have one added for wide band anyway. I'd much prefer to start with that, over buy the 98-01 pieces and tossing the rear half.

Even if I bought the 98-01 and kept the rear cats it was propably going to have to be reworked to clear the next crossmember behind the transmission. When I installed the two piece setup into my 99 Ranger the rear cats were going directly into that crossmember, since a full exhaust was coming they got deleted rather than spending the effort to reposition them. I also wanted to have flanges or clamps put near the transmission crossmember anyway to drop out the forward section for transmission work, so that would have been another modification to the later pipes.

 

[JoshT]

starting over on thread, post not needed

 

[JoshT]

Spoke with another exhaust shop today, this one was talking a lot closer to my language. He was rattling off things that I was thinking before I could ask. He was also favorable to using the Magnaflow cats, thinking that it was a better and cleaner option than trying to fab them.

So basically worked out to $400 plus materials to do dual "cat back". That is using 2.5" pipe, connecting to the "factory" flanges at the crossmember, and a dual in/out muffler instead of a separate crossover, and flanges at the back of the cat pipe to bolt that secti in and out. Probably around $600 at the exhaust shop, plus around $800 for the Magnaflow cats.

I've can actually save about $150 on the cats if I buy soon. I've got a 20% coupon for a dealer that also has free shipping, but I'm not sure how much long it's going to be good for.

@410Fortune

I know you're busy trying to put out fires on Eddie's truck, but you've probably stripped more V8 explorers and built more V8 rangers than any one else I know. What do you think about using the older 96-98 cat pipes in place of the newer 99-01 pipes? Think that there would be any isues with fitment?

I know you'd likely ditch them both and whip up something in house. I don't have that luxury and it seems like it'll work out better to buy cat pipes than have them fabbed locally.

 

[boominXplorer]

The main difference is the mounting flages between the cats on both sides near the cross member. The complete systems should swap but you can't mix and match different year pipes. Look at the pictures on rockauto.com and you'll see. I modified my cross member on my ranger to get the pipes to fit.

 

[JoshT]

Yes, swapping out the complete system was the question. I knew you couldn't mix and match. The 98+ the banks are separated with the rear cat made into the same pipe as the front cat. On the earlier systems the rear cats are combined into one assembly and separate from the front cats with flanges.

When my current exhaust was scabbed together the shop removed the rear to route pipes around a crossmember, and of course they didn't return the removed cats. Even reinstalling all 4 cats with the new system, I think the earlier assembly would be preferred because of the flanges before the rear cats. The shorter pipe sections will make it earier to manhandle the pipes and work around the transmission crossmember. They'll also allow for easy removal for the forward section of of pipes for servicing the transmission.

It makes sense that the systems would interchange. The manifolds are different, but interchangeable and the frames are prectically the same. I wasn't sure about the mounts at the back of the transmission, but they appear to be the same. I know that O2 sensors changed some time during the run, but it looks like that may have just been connectors and that their location in the pipes stayed consistent.

I'm thinking that the earlier system is going to be the best fit for my application, primarily because of the shorter sections to work with.

 

[boominXplorer]

I ran the earlier style on my ranger build. Even put all 4 cats on it just incase emissions ever became an issue.