CAT delete on a GenIV ACR?

[TexasTonka]

I am in one of the last 'free' cities in Texas and we don't have emissions check for our inspections so I can delete the cats in my ACR if I choose. Questions is should I? The car is a Hennessy 650R so it has their in house made headers, 3" cats and 3" exhaust. I do not know who made the mufflers or cats.

I was thinking of deleting the cats to give me a better flowing exhaust and a bit more HP in the higher RPM band. From those that have done this, do you recommend or what is your advise/comments?

As far as sound, my RT/10 had no cats with headers and B&B- no issue with sound or smell. My GTS had no cats with B&B- loud inside but otherwise fine. My SRT10 Ram has no cats and can't tell- its fine. Not worried about it being too loud outside, but if it has stupid drone inside or any other ill effects that is what I am looking at finding out before spending the money on cat deletes.

As far as O2 sensors, with the MOPAR PCM do I need to use simulators or does the PCM take care of that?

Appreciate the input!

[Shooter]

Flatout had MM Headers, with no cats on his 08 ACR and it sounded pretty good. Made good power too.

[FLATOUT]

Mopar ECU will take care of the code issue. I am taking them off my TA soon.

[TexasTonka]

Great- looks like the ACR will be louder very soon. How did you guys do the delete? Modify the factory pipe and have a local shop weld in a straight pipe or buy a specific part?

[FLATOUT]

I just ordered my headers without cats. For my Gen V I am fabbing something up.

[JonB ~ PartsRack]

It will be VERY louder very soon! all the sound and any drone you have now will just be louder.

Smelly too while idling, traffic stalls....

Mopar PCM stops the CELS, and stops the burble/backfire of catless sidepipes.

Catless on a RAM does not compare, du to 12 extra feet of tailpipes.

[98intrigue]

I have a set of OEM cats that you can use to gut the cats so if you don't prefer the noise, you can just go back to your high flow cats. Both of my Vipers didn't have cats, but I prefer loud noises!

[TexasTonka]

I have a set of OEM cats that you can use to gut the cats so if you don't prefer the noise, you can just go back to your high flow cats. Both of my Vipers didn't have cats, but I prefer loud noises!

Appreciate it! Does the OEM Cat set up have 3" in/out connections?

[venomous08]

Appreciate it! Does the OEM Cat set up have 3" in/out connections?

No they don't.

Downstreams are turned off with the mopar controller. To avoid them eventually getting chaffed or burned out, don't install them.

[TexasTonka]

Anyone have experience with no cats and Corsa cat back with long tube headers? Granted loud, but windows up on highway do you get the drone still?

[noisy]

Mine is literally straight pipes. No cats and mufflers. I will look for some audio. No fire either unfortunately so don't expect one.

[XSnake]

I have a 3" X exhaust for sale in the classifieds

[noisy]

https://www.youtube.com/watch?v=iVsoi9QrWME

[TexasTonka]

Nice ride but I need the mufflers for a few tracks around here. Cat delete should be more than enough sound, looking for better flow & breathing ultimately. Mufflers are a straight through design.

[Roddy]

I have no cats, the sounds is awesome, the smell is not awesome, worse with side pipes... I'm planning to install High flow cats.

[FrgMstr]

Anyone have experience with no cats and Corsa cat back with long tube headers? Granted loud, but windows up on highway do you get the drone still?

Belanger headers, no cats, 2.5" Corsa. Car sounds great. I don't get any drone with the Corsa that bothers me at all.



Had to get rid of the straight pipes.....holy mother of god that thing was loud. Might be OK in a coupe, but long road trips in a vert did not go together.

[TexasTonka]

Notice any difference at all in dyno numbers going from straight to the corsa? I would assume you would gain a bit of torque with the corsa with the added back pressure.

Think I am going to start with cat delete and if the Hennessy exhaust is too loud then move to a Corsa 3"

[FrgMstr]

Notice any difference at all in dyno numbers going from straight to the corsa? I would assume you would gain a bit of torque with the corsa with the added back pressure.

Think I am going to start with cat delete and if the Hennessy exhaust is too loud then move to a Corsa 3"

I never did a direct dyno comparison to see the different between straight and Corsa. But ran straight pipe at 2.5" as well except for the tip.

[Late Apex]

On my 09 ACR I did hi flo cats with amazing results and NO CEL as I had one of the best Viper techs do the install along with Belanger headers and NO PCM either. Unless strictly a track car I would not do total cat less.

[Viper.954]

I just ordered my headers without cats. For my Gen V I am fabbing something up.

I am under the impression that headers don't do anything for a Gen V with out a tune. I'm also under the impression that there are no tunes available for Gen V's. I never even considered removing the cats because of the no tune option. Am I wrong on all three points?

[2010.Blue.White.ACR]

Mopar makes a set up

[FLATOUT]

I am under the impression that headers don't do anything for a Gen V with out a tune. I'm also under the impression that there are no tunes available for Gen V's. I never even considered removing the cats because of the no tune option. Am I wrong on all three points?

You are right about point one and incorrect about points 2 & 3. HPTuners has been very successful at tuning both gen IV's and V's. I will be doing this at the same time.

[TexasTonka]

Well surprise, surprise, surprise!

I was only going off the build sheet of the car and that a full Belanger with cats seems louder than mine. We stripped off the side sill today to take a gander at just what we were working with and voila! There are no cats. Goes straight from collectors to a smooth elbow to a small muffler(looks to be magnaflow) to a straight cut tip. All 3" stainless.

This system is not as loud as a Belanger with cats, and there is absolutely no smell or flames shooting out the side. I guess every car is different.

Thanks for the advise on everything. Every question asked and answered helps every member here.

[Bill Pemberton]

Harder to sell, smells to high heavens, and no real advantage -- Snake needs some back pressure.

Personally think it is a waste , and most of us see good HP gains with high flow or stock cats. The odor bugs the heck out of many , and it can really affect selling it later. Mopar PCM, ACR-X Headers, factory cats , polished intake and my ACR is hitting 670hp with nothing else done. Like the solid torque curve and she doesn't have the unburnt fuel smell on the track or cruising - just my humble opinion.

[TexasTonka]

Harder to sell, smells to high heavens, and no real advantage -- Snake needs some back pressure.

Personally think it is a waste , and most of us see good HP gains with high flow or stock cats. The odor bugs the heck out of many , and it can really affect selling it later. Mopar PCM, ACR-X Headers, factory cats , polished intake and my ACR is hitting 670hp with nothing else done. Like the solid torque curve and she doesn't have the unburnt fuel smell on the track or cruising - just my humble opinion.

670?? I assume to the crank. If you are 670 to the wheel TAKE MY MONEY and teach me!

I was looking into cat deletes because I thought my car had high flows on it, per the Hennessy invoice. I have zero smell, zero odor, zero flames, zero issues. I was VERY surprised to see my car did not have cats when we took the side sills off today.

All I have is GenV intake, Hennessy headers, cat delete pipes and small magnaflow muffler. Car is quite to me with no unburnt fuel smell to it, or any other negatives I have been warned about. As said before I fully thought it had a restrictive cat and muffler set up.