ROE High-Flow Cats Questions

[pocketAA]

I have a couple of questions.
1) Is there any cutting/weilding when removing the stock cats?
2) Do I have to do anything special before removing the stock cats (disconnect battery, etc)?
3) Is there any weilding required when installing the ROE cats?
4) Do I have to get the CPU recalibrated to account for the high-flow cats?
5) Any other tips?

Thanks!

 

[jdoc7]

I have a couple of questions.
1) Is there any cutting/weilding when removing the stock cats?

Yes, you have to cut the cats at the inlet side

2) Do I have to do anything special before removing the stock cats (disconnect battery, etc)?

No

3) Is there any weilding required when installing the ROE cats?

Welding is not mandatory but when you cut the cats at the inlet, it is close to the turn-out elbow and clamping at this point was not sufficient for a good seal, at least on my setup.

4) Do I have to get the CPU recalibrated to account for the high-flow cats?

I have a 98' and did not have to do anything. Later models may require modifying 02 sensor.

5) Any other tips?

Enjoy the new sound!

 

[ViperJoe]

I see you are using the Random Tech cat back.....3" system I assume?

Are the cats 3" in/out?
If so you will need an adapter to transition from the stock header pipe (2-1/2?) to the 3" of the hi-flow cat.

On my RT hi-flows I have the adapter welded to the header pipe and welded into the inlet side of the cat. The hi-flow outlet to the cat-back inlet joint has a muffler clamp, as do all the other joints.

I used a Sawsall to cut the stock cat out.

Good luck!

 

[pocketAA]

The cats on the car are the stock cats. I am also assuming the Random Tech cat-back is the 3" system, but not sure when I bought the car that is what the orig. owner put on.
So are the cats attached right after the header ends?
I do not feel like spending a ton for someone to do this, when I am sure I can do it my self, but I need some help, is there any do-it-yourself guide for installing the ROE cats?

Thanks

 

[ViperJoe]

Here are my RT's on the 98, you can see the adaptor welded to the header pipe and the adaptor welded to the cat.

 

[jdoc7]

Hey ViperJoe, that's a great picture to illustrate the weld between the header turnout and inlet adaptor. As you can see, that weld is still very close to the bend and putting a clamp around that area would be insufficient to prevent leaks. Mine looks similiar except I used a Roe metallic substrate cat. (oh, and my welds don't look nearly that nice!)

 

[pocketAA]

Thanks for the image ViperJoe. It says on Roe's website that the cats can just be clamped in, is this a misprint, or welding would be the optimal way to go? Anybody have this done by a shop and does anyone know of a cost to get these cats installed?

Thanks

 

[Asp Man]

If you are worried about Viper tax on the exhaust work you could take the flex pipe/cat inlet pipe off of the car to have either the adaptor or the cat (or both as in the above pic) welded on. (Measure everything three times!) It is more work, but you'll avoid the V tax for sure.
If you don't and get it done while on the car make sure that they know what they are doing at the exhaust shop. Disconect the battery before doing any welding, protect the painted areas, don't leave it at the shop, don't let them "test drive" your car, etc. All the common sense stuff that may be forgotten at times.
Or, you may be surprised at how little a good, honest exhaust shop may charge to do it. Chech around, you'll probably get a different price from every shop you visit.

 

[ViperJoe]

After lining up everything like a gazzillion times, check, double check, triple check, I marked the header pipe, adaptor, and hi-flow.

I marked them vertically and all the way around and also put aligning marks horizontally across all pieces in different places.

Then I pulled off the header pipe adaptor and highflow and took all the pieces to a friends machine shop.

Re-installation was perfect