Gen 3 Exhaust Cats question

[dreamcarviper]

I know this has probably been debated at length somewhere but can't seem to find the exact answer to my question.
My objective is to reduce cabin heat, get a better sound and increase power if i can. My 2003 will not be tracked. All this while being able to pass emisions (Ontario) and not have the dash turn into a Christmas tree.
I don't want to change the headers but will remove the cross pipe, change the cats and go with a Corsa exhaust most likely.
My questions is about the cats specifically. There are numerous cats available but from what I have noticed there are two designs, one with flex pipe and one without (ex Parts Rack versus ROE racing)
Is there one better that the other? I would think that the one with the flex pipe would move with the engine and prevent crakcs but I am not a pro and figured I would ask those with more experience than me.

thanks in advance

[shagsf16]

I just put in JonB's (Parts Rack) Belanger Hi-Flow Cat exhaust on my 2003 SRT and I absolutley love it. It will definitely meet your objectives of reducing cabin heat and getting better sound...and JonB's knowledge and customer service is just awesome. I have only had it for a couple weeks but no issues with triggering any lights. So while I can't speak specifically about whether it is better with/without flex pipe, I can give a strong endorsement for JonB's Hi-Flow Cat option!

[dreamcarviper]

Thanks I've heard good things about those. Anyone have had issues in the long term? I'm just trying to figure out if there woulds be any cracks without the flexpipe. Don;t want to have to reinstall anyhting

[Parmenion1_00]

How have you found the Hi Flo Cats? I am also in process of deciding (been a bleedin' headache..!) what Hi Flo's to get re: Flex or no flex.
Like you dreamcarviper, i was wondering if the solid cats would crack as no flexibility and after all.... there surely has to be some kind of 'movement' from the V10 ponies..... :-)
Looking to keep standard headers but have Hi Flo CATS and most likely Corsa system although mulling over keeping stock mufflers. Not sure on that yet.
Mine is a 2005 GEN3 Viper.

[Mopar'er no car]

Engine moves. Stock system has flex pipes. Not sure why you would want solid mount pipes. This has been a major bellanger design flaw since day 1. Ive heard all the reviews, "Ive had mine for 10 years and a million miles". Heard of 3 diffrent cars having issues based off this.(just this driving season) One gentelman tried getting this issue resolved only to have Lou Bellanger cuss him out over the phone. He wanted the issue resolved and never even mentioned that bellanger pay for it. All he got was a earfull on how smart Lou was himself and that his product was perfect in every way. Exact words

[Stealth78]

Engine moves. Stock system has flex pipes. Not sure why you would want solid mount pipes. This has been a major bellanger design flaw since day 1. Ive heard all the reviews, "Ive had mine for 10 years and a million miles". Heard of 3 diffrent cars having issues based off this.(just this driving season) One gentelman tried getting this issue resolved only to have Lou Bellanger cuss him out over the phone. He wanted the issue resolved and never even mentioned that bellanger pay for it. All he got was a earfull on how smart Lou was himself and that his product was perfect in every way. Exact words

I'm scratching my head right now and can't wait to get home from work to look at my stock pipes that I took off. I don't remember having flex on the factory mids???? I could be losing my mind. I have had zero issues with the solid mids!

[Stealth78]

Correction... Stock mids do have flex on them. My bad. Although I have not had issues with my solid mids thus far.

[Steve M]

Engine moves. Stock system has flex pipes. Not sure why you would want solid mount pipes. This has been a major bellanger design flaw since day 1. Ive heard all the reviews, "Ive had mine for 10 years and a million miles". Heard of 3 diffrent cars having issues based off this.(just this driving season) One gentelman tried getting this issue resolved only to have Lou Bellanger cuss him out over the phone. He wanted the issue resolved and never even mentioned that bellanger pay for it. All he got was a earfull on how smart Lou was himself and that his product was perfect in every way. Exact words

I too have been called an idiot by Lou, and I agree, it isn't the best design. I'm running them on mine, so we'll see what happens. Although you do get rid of the stock flex section, you also get rid of the front exhaust mounts. This gives the exhaust room to move around (and there's plenty of room). If anything, it'll put more stress on the stock exhaust manifolds...I'm curious to see if mine ever develop cracks from this.

[SlateEd]

I have RandomTech Hi-Flo Cats... they're what JonB had available something like 6 years ago when I needed to change out the stock. I have the Corsa cat-back system behind them and the stock exhaust manifolds in front of them.

on the topic of breaking.. I can't speak to Belanger, but the RT cats have been fine since installation. That's easily 25,000 miles ago.

to address your questions
- power, it certainly should make more, but honestly you're not going to feel 8-10 HP on 530 so I really can't tell you. Tuned the car after several mods, so the dyno numbers account for everything, not just cats. advice - don't get nuts over 5hp claims one way or the other.
- cabin heat - definitely lower with high flow cats, but not nearly as big a difference as the cat-back system alone (I did these in steps a few years apart) Getting rid of that Gen3 crossover pipe came first, and made the biggest difference
- sound - subjective here. The tone is great to me, and others have commented on how vicious it sounds from outside the car. It's aggressive and harsh at higher RPM, deep at lower RPM. But after 25,000 miles plus, it's getting a little loud and I'm missing the days of just a Corsa Cat-back with the rest stock. It's loud at mid-throttle and blistering at WOT.
- BONUS - with a (little rich) tune in the car I'm throwing 3' worth of flame out both sides if desired... great for getting left lane blockers to move especially at night. It would not do that with stock cats.

so more power - all of what you mentioned together will help
less heat - the cat-back makes the most difference there
sound.... outside the car, go for the cats... but for me, the sound inside the car was best when it was stock manifolds, stock cats, Corsa cat-back

[SNKEBIT]

I have sold many sets of headers, no cracking anywhere. AND I have the best warranty in the viper world. Plus, I don't call you a dumbass.

[Mopar'er no car]

I too have been called an idiot by Lou, and I agree, it isn't the best design. I'm running them on mine, so we'll see what happens. Although you do get rid of the stock flex section, you also get rid of the front exhaust mounts. This gives the exhaust room to move around (and there's plenty of room). If anything, it'll put more stress on the stock exhaust manifolds...I'm curious to see if mine ever develop cracks from this.

I had a simple question. It turned into, "ive been buliding Vipers for years". I said, you build Vipers, i had no clue.

After hearing others experineces combined with my own its quite clear that Lou is a welder and nothing more. Id have ray charles weld me an exhaust with his feet before id spend my money with that Clown.

[dreamcarviper]

thanks SlateED for the info.
I've delayed my purchase a couple of months but I've decided Cat Back.

[Parmenion1_00]

Interesting comments on this topic thread here :-) Plenty of food for thought for sure.....

But.... i am not entirely sure on the Hi Flo CATS...... i think Corsa cat back is a no brainer so i will avoid Belanger (offered a deal on belanger catback and hi flo CATS) But have decided if i get a catback it will be Corsa. That i am now 100% sure of.
But..... Hi Flo CATS? Should i get them? (Partsrack supplied at that)
1- Stock headers, Hi Flo CATS from partsrack (or any other Hi Flo suppliers/make you guys recommend..???) And corsa catback
Or
2- Stock Headers, stock CATS, Corsa catback

I need to get this nailed on right first time coz shipping to Australia let alone buying is very expensive indeed!! Pinged on import tax too :-(

[SNKEBIT]

Your stock manifolds WILL crack. Have changed out many sets of gen 3 manifolds. (factory hangars still intact)

[Stealth78]

I also have factory manifolds, RT hi-flo's and Corsa cat-back. Not sure if there is any added strength to the GenIV manifolds over GenIII but again so far so good for me. In regards to the lack of flexpipe and the motor moving, would it be beneficial to add Woodhouse motor mounts to stiffen it up to refrain from putting so much strain on the manifolds?

[Stealth78]

Additionally, I have heard controversial comments in regards to the Woodhouse motor mounts on a GenIV due to knock sensors. If true would I be okay to install them now that I'm on HPT?

[Steve M]

Additionally, I have heard controversial comments in regards to the Woodhouse motor mounts on a GenIV due to knock sensors. If true would I be okay to install them now that I'm on HPT?

Yes...you have full control over the knock sensors, and can decrease the sensitivity if necessary (I've needed to on mine even with the stock mounts).

The only thing I've heard is that it can lead to some pretty serious vibration in the cabin, so I'm going to hold off on poly mounts until my stock ones give up the ghost.

[Parmenion1_00]

Well.... i am none the wiser. Some say recommend hi flo cats, some say no trouble, some say avoid due to trouble.
Jeez........ smh.

Perhaps brand specific? Are ALL hi flo cats with flexi pipe bit? Is it high flo make/brand specific perhaps...?

[SNKEBIT]

I also have factory manifolds, RT hi-flo's and Corsa cat-back. Not sure if there is any added strength to the GenIV manifolds over GenIII but again so far so good for me. In regards to the lack of flexpipe and the motor moving, would it be beneficial to add Woodhouse motor mounts to stiffen it up to refrain from putting so much strain on the manifolds?

Gen 4 manifolds are a lot stronger. Gen 3's are junk. lol

[SlateEd]

Interesting comments on this topic thread here :-) Plenty of food for thought for sure.....

But.... i am not entirely sure on the Hi Flo CATS...... i think Corsa cat back is a no brainer so i will avoid Belanger (offered a deal on belanger catback and hi flo CATS) But have decided if i get a catback it will be Corsa. That i am now 100% sure of.
But..... Hi Flo CATS? Should i get them? (Partsrack supplied at that)
1- Stock headers, Hi Flo CATS from partsrack (or any other Hi Flo suppliers/make you guys recommend..???) And corsa catback
Or
2- Stock Headers, stock CATS, Corsa catback

I need to get this nailed on right first time coz shipping to Australia let alone buying is very expensive indeed!! Pinged on import tax too :-(

If I could do it again, I would probably stick with option 2, only because I need to be a little careful with my hearing for work. If you are okay with the car getting pretty loud, go for the hi-flo. You pick up a couple HP (really not much), you definitely get cooler sill temperatures, and if it's tuned a little rich you'll throw flames

[Mopar'er no car]

If I could do it again, I would probably stick with option 2, only because I need to be a little careful with my hearing for work. If you are okay with the car getting pretty loud, go for the hi-flo. You pick up a couple HP (really not much), you definitely get cooler sill temperatures, and if it's tuned a little rich you'll throw flames

Why would i want it to shoot flames?

Said NO ONE..

[Dan Cragin]

Long term I have not had the best luck with aftermarket cats. They often fail over time and sometimes wont pass the catalyst monitor. They make more power and reduce heat, but many times dont last the life of the car.

As long as you know that, the benefits are there. Most my experiences have been with modified cars, which are harder on cats.

To improve power and reduce heat, you can remove the secondary catalyst. The car will still pass the monitor. Of course this is for off road use only and is bad for the environment.

[Stealth78]

Yes...you have full control over the knock sensors, and can decrease the sensitivity if necessary (I've needed to on mine even with the stock mounts).

The only thing I've heard is that it can lead to some pretty serious vibration in the cabin, so I'm going to hold off on poly mounts until my stock ones give up the ghost.

Hey Steve, I can't say for sure about the motor mounts but I truly wonder if the majority of the vibration comes from the trans mount. As soon as I swapped in the Woodhouse poly trans mount last summer I instantly had a mean vibration between 2000 - 2500 rpm's. My factory mount was basically brand new at the time, I think around 4,000 miles on it, I simply swapped it out for a crisper shift and to see if it helped eliminate wheel-hop, in which it did aid with that. I am currently in communication with Doug (DSE), not sure if anything will come of it but I had asked Doug if there was any way to meet in the middle of the factory mount and the poly mount, stiffness wise that is.

- - - Updated - - -

Gen 4 manifolds are a lot stronger. Gen 3's are junk. lol

Perfect!