pros and cons on removing cats

[terry5357]

Just buy some hi-flow cats they’re not expensive and you stay legal and no CEL

 

[Pentalab]

How do you re-use OEM cats... with LT's ??

 

[06 T-RED S/C GT]

Just buy some hi-flow cats they’re not expensive and you stay legal and no CEL

If they pass OBDII emissions test, then hi-flow cats are legal. If they don't pass OBDII? they fail emissions and are not legal. Adding mini cat/non-foulers to the rear 02 sensors help get past OBDII emissions testing on the older 4.6L 3valves, but are hit and miss on the 11-current Coyote 4valves.

How do you re-use OEM cats... with LT's ??

Cut the OEM mid-pipe section and clamp the OEM cat pipes to the LT mid-pipe crossover. Personally, I wouldn't bother going through all that hassle. IMO you're much better off just getting the complete LT header exhaust that includes the shorter LT mid-pipe with high-flow cats

 

[Norm Peterson]

How do you re-use OEM cats... with LT's ??

Like most any other non-OE and non-prefabricated exhaust system modification.

Norm

 

[MrAwesome987]

You can do a lot with those two tools lol

 

[fdjizm]

No duct tape?

 

[Dino Dino Bambino]

Can't use regular duct tape. Need high temp duct tape.

 

[Norm Peterson]

Regular duct tape finds opportunities that aren't under the car.



Norm

 

[Pentalab]

IMO you're much better off just getting the complete LT header exhaust that includes the shorter LT mid-pipe with high-flow cats

I had the LT's installed, including a new pair of gaskets. The (much shorter) mid pipe + hi-flo catted H seemed like a no brainer at the time. Without a lift, you would have a helluva time installing the entire mess. The hi-flo cats reside below both seats. Back end of the new catted H section bolts to aft oem section... which goes up and over the axle. FRS-500 mufflers used, way too loud, + drone, so a pair of SS pypes M80's welded inline.... just b4 axle.

I bought 2 complete systems, one for a local buddy.... so we got an excellent price. The oem H section, sometimes has a disc, dead centered, with a 3/8" puny hole in disc, sometimes 1", sometimes 1.25".... and no disc at all..and a 2.5" hole.... go figure.

 

[fdjizm]

Regular duct tape finds opportunities that aren't under the car.
View attachment 70134


Norm

It looks... excited...

 

[Dino Dino Bambino]

The hi-flo cats reside below both seats.

At least they'll keep your ass warm in the winter.

 

[06 T-RED S/C GT]

I had the LT's installed, including a new pair of gaskets. The (much shorter) mid pipe + hi-flo catted H seemed like a no brainer at the time. Without a lift, you would have a helluva time installing the entire mess. The hi-flo cats reside below both seats. Back end of the new catted H section bolts to aft oem section... which goes up and over the axle. FRS-500 mufflers used, way too loud, + drone, so a pair of SS pypes M80's welded inline.... just b4 axle.

I bought 2 complete systems, one for a local buddy.... so we got an excellent price. The oem H section, sometimes has a disc, dead centered, with a 3/8" puny hole in disc, sometimes 1", sometimes 1.25".... and no disc at all..and a 2.5" hole.... go figure.

Without a lift, I wouldn't even consider going through the hassle of trying to install a LT exhaust system nor the patience for that matter lol. I'd rather just have a performance-oriented shop that has a lift do the installation and know that it's done right the first time. I actually considered looking into ditching the OEM cats towards splicing in a pair of Magnaflow high-flow cats to my set of cat delete pipes from the Mac o/r ProChamber I ran before adding the Pypes cut n clamp X pipe to the OEM catted downpipes but was concerned that running high-flow cats paired with Borla ATAK mufflers would be way too loud and end up droning like a bitch. Plus I didn't want to cut any portion of the ProChamber o/r downpipes as I intend on selling my o/r ProChamber. Therefore I decided that taking the cut n clamp X pipe to OEM cat route would be the best option for my particular application and also have a piece of mind knowing that my car will pass OBDII emissions if necessary. Anyhow at least for the time being, I'm satisfied with my current exhaust setup in which the Borla ATAK's produce a nice deep tone that isn't obnoxiously too loud inside the cabin and the X pipe along with the OEM cats in place provide IMO more of a refined V8 sound but still has that deep muscle car rumble of an H pipe when shifting through the gears without producing any rasp whatsoever

 

[hoyabob2003]

I learned my lesson a while ago when I tried to go catless and could not stand the highway drone and raspiness.

 

[06 T-RED S/C GT]

I learned my lesson a while ago when I tried to go catless and could not stand the highway drone and raspiness.

Same here

 

[fdjizm]

I learned my lesson a while ago when I tried to go catless and could not stand the highway drone and raspiness.

Mid-mufflers cures that

 

[Pentalab]

Mid-mufflers cures that

SS Pypes M-80's would also work... relatively inexpensive from AM + most other shops.

 

[06 T-RED S/C GT]

Mid-mufflers cures that

From my understanding, adding mid-mufflers to axle back mufflers IMO defeat the purpose of curing resonance drone caused by the majority of mufflers that are located after the rear axle. Therefore I'd recommend doing the mid-muffler setup that eliminates the axle back mufflers altogether such as the Pypes mid-muffler cat-back exhaust and Roush extreme cat-back with mid-mounted resonators that also include axle-back delete pipes.

SS Pypes M-80's would also work... relatively inexpensive from AM + most other shops.

The Pypes M-80 mid-muffler cat-back with axle-back delete pipes would be much more effective IMHO.

 

[fdjizm]

I have the pypes m80 mid mufflers, and SVE straight through axle backs. Not experiencing drone, probably chambered mufflers may have an issue droning then.

 

[06 T-RED S/C GT]

I've had droning issues with 3 different straight-thru axle-back mufflers. First was Magnaflow street mufflers, followed by Borla S-type (stingers) and now I'm currently running Borla ATAK mufflers which have striaght-thru multi-core tubes. From my personal experience, Borla S-type mufflers have the worst drone out of all straight-thru mufflers I've used and IMHO have just as many droning issues as most chambered mufflers such as Flowmaster and Mac Performance. The only straight-thru design axle back mufflers that I'm aware of that do not drone are from Corsa performance exhaust and the Ford Performance FR500 part#M-5230-S. Although I'm not very familiar with the SVE axle backs, you would think by adding them together with mid-mufflers would also reduce the overall volume and end up not being quite loud enough, unless of course your running either LT headers with high-flow cats or factory/shorty headers with an O/R mid-pipe

 

[07 Boss]

NO DRONE ZONE