madman
Enthusiast
You can't install CT and leave crossover. It comes in one piece per side. They have other exhaust which accommodates crossover. But I don't see a point of leaving that radiator in the car.
Aftermarket Exhaust
- Thread starter Flash1034
- Start date
YellowViperSRT10
Enthusiast
Yes, one main reason i want an exhuast is to get rid of the crossover. But the only reason i asked was people said if you retain the crossover it sounds better? is that true or what?
YellowViperSRT10
Enthusiast
So i am assuming you did not like the sound of the Corsa?
Maintaining the crossover makes the sound more even, not necessarily better. For many of us the added performance was the objective. Sound quality was still important but secondary to performance. Therefore keeping the crossover was not a possibility.
Racer Robbie
Enthusiast
"would that make it sound less like a UPS truck?"
yes
yes
valentine_viper
Viper Owner
Seems like most people are replacing stock exhausts for better sound and/or less heat. I haven't heard much about prformance gain. All BS aside, is there any performance gain to be had from an aftermarket exhaust on a stock motor?
Racer Robbie
Enthusiast
Here are the number from our AtRo racing exhaust system with hi flow cats vs stock.
STOCK
523.65 EHP & 572.00 ETQ @ 5400 RPMs / 445.1 RWHP & 486.2 RWTQ @ 5400 RPMs
ATRO RACING STREET / TRACK EXHAUST SYSTEM
541.18 EHP & 588.94 ETQ @ 5400 RPMs / 460.0 RWHP & 500.6 RWTQ @ 5400 RPMs
INCREASE OF = 17.49 EHP & 16.94 ETQ @ 5400 RPMs / 14.90 RWHP & 14.00 RWTQ @ 5400 RPMs
I am redoing our web site and it will have more dyno numbers by the end of the day.
Robbie
AtRo racing Products
http://www.members.aol.com/AtroRacingTeam/PRODUCTS/AtRoRacingsProductCatalog
If you are not doing any changes to the headers or the cats, there is so much the cat-back exhaust can do on a SRT-10. Mopar Street & Race Exhaust and Corsa Track seem to be the popular options with Mopar Race being the louder and better flowing.
However, I'd look into having an exhaust shop make you a custom exhaust. It would save you bunch of money and you can tune it down or up anyway you want.
I have a custom 4" exhaust system on my car and it sounds awesome but I wouldn’t put it on a N/A or Paxton car. It will be just too loud. It’s little tricky to make the 4" system fit in there but once it fits it doesn’t move at all...
However, I'd look into having an exhaust shop make you a custom exhaust. It would save you bunch of money and you can tune it down or up anyway you want.
I have a custom 4" exhaust system on my car and it sounds awesome but I wouldn’t put it on a N/A or Paxton car. It will be just too loud. It’s little tricky to make the 4" system fit in there but once it fits it doesn’t move at all...
viperbob
Enthusiast
I just read that if the Mopar Race Exhaust is installed, the Race Controller and Camshaft are needed - really????
How about the Mopar Street Exhaust?
How about the Mopar Street Exhaust?
No. You don’t need the Mopar Race controller or Mopar camshaft if you install the Mopar Race exhaust but because the race exhaust eliminates all the cats, you will need some sort of tuning to get rid of the error codes and tune the car to run without the cats. Otherwise, you will get codes and the car will run very rich.
Sorry but you are incorrect my friend.
The A/F mixture is controlled by the first O2 sensor (upstream), therefore it makes absolutely no difference whether you have one cat, no cat or ten cats.
Yes there will be a "check engine light" when the O2 molecule % in the exhaust is the same in the upstream and in the downstream (after cats) sensors. That is why an O2 simulator is needed (or reprogram) on the second (downstream sensor) when the cats are removed.
Cheers!
Sorry but you are incorrect my friend.
The A/F mixture is controlled by the first O2 sensor (upstream), therefore it makes absolutely no difference whether you have one cat, no cat or ten cats.
Yes there will be a "check engine light" when the O2 molecule % in the exhaust is the same in the upstream and in the downstream (after cats) sensors. That is why an O2 simulator is needed (or reprogram) on the second (downstream sensor) when the cats are removed.
Cheers!
Don’t think so.
First of all, you don’t need the Mopar Race controller if you install the Mopar race exhaust. Period. That’s the answer to the question.
If you eliminate the cats, check engine light will come on. You may use 02 simulators or you can delete the rear 02 sensors by tuning.
If you don’t have 02 simulators and if you have not tuned the ECU for running without the cats, the check engine light will be on. The higher flow due to not having the 4 flow-cutting cats will lean you out a little and the ECU will see this and counteract, causing the car to run rich. It won't be running pig-rich but still it will be running a little rich. Again tuning will take care of this.
Cheers.
If you don’t have 02 simulators and if you have not tuned the ECU for running without the cats, the check engine light will be on. The higher flow due to not having the 4 flow-cutting cats will lean you out a little and the ECU will see this and counteract, causing the car to run rich. It won't be running pig-rich but still it will be running a little rich. Again tuning will take care of this.
Cheers.
[/b]
Ok I didn't say everything was wrong. We are both in the same page regarding the O2 sims.
Your statement above is off. There is no reason why the ECU will "counteract". Engine Control Unit is there just for that, to control the engine function. If your car is running lean, the injectors will fire longer until this misbalance is fixed. Of course, we are talking about an otherwise stock car, not a monster that needs extra fuel pumps, bigger lines, bigger injectors, etc.
Bottom line. Take out the cats and install O2 sensor simulator. Reset computer, and the car will run just fine.
Cheers!
Carleton
Viper Owner
ViperBob
I do have the Mopar Race Exhaust (no cats) w/K&N filters. The engine was running rich but after a DC performance reflash of the ECM the car ran noticeably smoother/faster.
Carleton
I do have the Mopar Race Exhaust (no cats) w/K&N filters. The engine was running rich but after a DC performance reflash of the ECM the car ran noticeably smoother/faster.
Carleton
Bob K
Enthusiast
I have the race exhaust and the race engine controller with no O2 sims and I have gotten no check engine lights and all of the accessories work. I have misplaced the dyno sheets so I can't comment on the A/F.
Bob K
Bob K
If you don’t have 02 simulators and if you have not tuned the ECU for running without the cats, the check engine light will be on. The higher flow due to not having the 4 flow-cutting cats will lean you out a little and the ECU will see this and counteract, causing the car to run rich. It won't be running pig-rich but still it will be running a little rich. Again tuning will take care of this.
Cheers.
[/b]
Ok I didn't say everything was wrong. We are both in the same page regarding the O2 sims.
Your statement above is off. There is no reason why the ECU will "counteract". Engine Control Unit is there just for that, to control the engine function. If your car is running lean, the injectors will fire longer until this misbalance is fixed. Of course, we are talking about an otherwise stock car, not a monster that needs extra fuel pumps, bigger lines, bigger injectors, etc.
Bottom line. Take out the cats and install O2 sensor simulator. Reset computer, and the car will run just fine.
Cheers!
Still wrong..
I don’t know how to tell this to you but when the SRT-10 engine flows much more exhaust due to getting rid of 4 restrictive cats or installing high flow headers, this will lean out the engine little bit and the ECU will counteract by dumping more fuel and therefore making the car run rich.
Ask any reputable tuner and you will get the same answer.
Any otherwise stock SRT-10 with cat deletion or high flow headers will run rich unless the ECU is tuned.
Bingo!! Exactly what I’m talking about..
SRT-10’s will benefit a lot, not only HP number wise but overall ride quality wise from a custom tune after bolt-on mods like exhaust, intake, cam, etc.
Now all we need to do is convince zorroespanol...
How do you know? Not challenging you, just wondering.
I am not debating the benefits of a computer remapping, That'd be foolish.
Insomniac. I understand completely the increased flow with the removal of cats, of course, I've been around engines for a bit. quite a bit!
the ECU's job is to work in conjunction with the O2 sensor to regulate the AF mixture. The same way that it does when the weather is cold, or when you drive at an altitude. Otherwise we'd just have mechanical fuel injection, not electronic.
If the enrichment in AF mixture after the removal of cats is in fact correct, Then it maybe an innate defect from the SRT's ECU. But no ECU is supposed to work like that, period.
Cheers!
Carleton
Viper Owner
Z
When I took my Viper to DC Performance, at the dyno pull it showed it was running rich. I believe they said this was because of the Mopar Exhaust/no cats, but I could be mistaken.
The problem was corrected with the reflash.
Carleton
When I took my Viper to DC Performance, at the dyno pull it showed it was running rich. I believe they said this was because of the Mopar Exhaust/no cats, but I could be mistaken.
The problem was corrected with the reflash.
Carleton
AMAZING !
Our first testimonial that an exhaust / intake can improve the RIDE quality.
This thread clearly illustrates why EVERYONE here is an expert. Newbees beware, "I read it on the VCA Board" is NOT the gospel truth you may think it is.
Grunt
Enthusiast
I'm learning that. I'll ask, Who do you believe?
First of all, I didn’t say an exhaust / intake can improve the ride quality, I said a CUSTOM TUNE after bolt-on mods like exhaust, intake, cam, etc will improve the ride quality.
By ride quality, I meant how the engine performs throughout the power band, at idle, part throttle, WOT, etc. and how the car drives overall.
It’s obvious that I wasn’t talking about suspension, springs, wheels, tires, etc.
I’ll repeat, “Any otherwise stock SRT-10 with cat deletion or high flow headers will run rich unless the ECU is tuned.”
It’s obvious that I wasn’t talking about suspension, springs, wheels, tires, etc.
Yes, it was pretty obvious, nobody here thought that you wre refering to the actual suspension.
But I still disagree on the engine running rich after installing off-road exhaust...
Let's agree to disagree!
It’s obvious that I wasn’t talking about suspension, springs, wheels, tires, etc.
Yes, it was pretty obvious, nobody here thought that you wre refering to the actual suspension.
But I still disagree on the engine running rich after installing off-road exhaust...
Let's agree to disagree!
We already have one Viper owner saying that his car was running rich on the dyno after cat deletion and race exhaust with no tuning.
You don’t have to agree with me. Just believe in the dyno.
Put any otherwise stock SRT-10 with cat deletion, race exhaust and/or high flow headers on the dyno and look at the graph.
We already have one Viper owner saying that his car was running rich on the dyno after cat deletion and race exhaust with no tuning.
You don’t have to agree with me. Just believe in the dyno.
Put any otherwise stock SRT-10 with cat deletion, race exhaust and/or high flow headers on the dyno and look at the graph.
Ok, I thought about it and now I figured it out (BTW, you are wrong
)What happens is this: When you have CATS, the unburned fuel is burned at the cats (that's what they are there for!).
Therefore, when the cats are removed, this unburned is expelled through the exhaust.
But the original AF mixture (inside the combustion chamber) stays the same. There is no "over compensating" or anything in that matter. I just did not make any sense, if you know how an ECU works in closed loop.
Plus, at the dyno chances are you are running OPEN loop.
Capisce? I hope so! Read up on this somewhere else and you will understand.
Cheers!!
At WOT, the cal provides a measured fuel and spark based on the inputs. Exhaust back pressure or f/a ratio are not included. Thus there is no WOT adjustemnt to fueling resulting from improved flow. Thus improved flow decreases the f/a ratio.
Headers or cat delete should both result in increased exhaust flow and decrease the f/a ratio. Any other result is illogical. The fact that at WOT the stock cal is quite rich, and therefore still rich after minor flow improvements does not change the physics. More air flow, same fuel equals lower f/a ratio.
Headers or cat delete should both result in increased exhaust flow and decrease the f/a ratio. Any other result is illogical. The fact that at WOT the stock cal is quite rich, and therefore still rich after minor flow improvements does not change the physics. More air flow, same fuel equals lower f/a ratio.
Yes, I know. But read the thread and you won't see "WOT" being mentioned anywhere.
But you are definitely correct in what you are saying.
Grunt
Enthusiast
The ******* contest is getting old.
