I took off my cats and when I drive it, I have a headache

[Qualitywires.com]

My GTS is a bit louder and things that didn't rattle before seem to rattle a tad bit.

I put on Sean Roe's Cat simms and they seem to work great! My only concern is that I smell exhaust fumes, but could be from the new pipe burning off the surface oil....maybe it will go away. I really like how my car sounds now. It's loud! I'm not sure if the sound is giving me the headache or if it's the fumes. Fumes don't smell like fuel, smells like exhaust. It could be from staying up till 3 am putting my car back together. heh!

I noticed my car will spin the tires more easily than when I had my cats on. I guess it's a bit torquer than before. I had the 2 1/2 inch pipes on it and it really doesn't sound much different than the 3" ones I heard before.

anyone experience my dilemma?

 

[Doug Supercharged Vipers]

Adam -
Did you weld all of the pipes? If not, I suggest you weld the exhaust tubes leading in/out of the cats. A rear cargo cover helps eliminate some of the resonance. If the sound and smell still becomes unbearable try some high-flow cats.

Good Luck,
Doug

 

[BlackACR]

My car did the opposite than you car. My car had less of a gas smell when I removed the cats. Also, there is no more black suet on the ground when warming up, and on the rear facia. 110% happy, best thing I have ever done to my car. Watch out, some people will say they are going to turn you in on here for not having cats!!!!

**** tree huggers

 

[AJ]

i would say that !cats and/or better headers normally lift your hp/tq curves in the rpm range.. so you should lose some bottom end tq, but gain some hp at the top...

exhaust fumes are bad. what you describe means you are leakin exhaust before the catback and it is entering the cockpit. which means you should lift the car and use lighter to see where the draft is... wherever you have some you should weld the joint ot buy those funky looking wide metal bands with clamps at both ends that you can use to "patch" the connections. be very careful with the lighter not to touch any plastic parts, wires, etc... obviously..

on a second thought.. make sure that your exhaust is routed properly and suspended properly (rubber suspenders and all) and then just weld the whole thing together.. leaky exhaust will fail you on emissions too... if you have them in your state that is...

alex
00 m5
few other cars

 

[Qualitywires.com]

before I put my side sills on, I turned my car on and put my hand around the joints to feel any leaks..and it seemed to be fine. I don't smell fuel at all, I smell the exhaust gases I think. Would the fumes give me a headache?

I will have to double check the joints again, but I'm positive they are fine.

"for legal purposes" This car is for track and off road use only whe these modded pipes are on!".

 

[RECOIL]

I went with racing cats instead of no cats. Other Vipers I've been around with cat-deletes smelled heavily of gas when at idle.

For the first 100 miles or so, I did smell more gas then usual. It went away (or I became used to it).

Steve

 

[ACELLR8]

Ab,

Yes the fumes will give you a headache. I do not have any experience with the Viper and No cats, but I did take both cats (main cat & pre-cat) off of my RX7 and the fumes were horrible. I know I did not have any leaks, because a custom exaust shop in the area welded all the joints.
In that car it definintely increased horsepower and Boost, but I eventually opted to go with a High Flow cat the same as what I have on my RT.
The fumes were exactly the way you describe it, exaust fumes not gas fumes. It would really give me a headache if I had the windows open and was stopped at a light or in traffic. After the wife complaining of the fumes enough, Like I said I decided to go with High flow cats.
I personally would not get rid of the cats all together unless it was a mostly track car.
The good thing is the high flow cats for the Viper are reasonably affordable in comparison to everything else.

Ed

 

[onerareviper]

BlackACR,

You must be the exception. No cats usually equals bad smell. Get used to it, or put some high-flows on. With Sean Roe's cats you only lose a couple HP vs. no cats, and don't have to deal with the smell issue. I actually like the sound a lot better with the high-flow cats on. A little deeper sound and not as choppy. I tried no-cats first as well.

P.S. - With high-flow cats, side sills will get warm/hot, but not near as bad as stock cats. Gotta love that cool side-sill with no-cats. I do miss that.

 

[Qualitywires.com]

yeah.that's one thing I like is no heat on my toes and side sills!

Aceller8..thanks for your input. I think the exhuast fumes might be seeping in from the rear vents of the Viper....not sure if it is. But you hit it on the nail what I am going through.

 

[BlackACR]

I dynod at RTB yesterday. I dont have a scanner but, if you would like to look at them come on down.

 

[Sean Roe]

The smell of fumes does seem to vary quite a bit. That's my experience at least. At the Justin Bell School (back when they were running Vipers and I was doing instructing with them), you could get in one car with no fumes, then the next one would make your eyes water.
One thought on what it *might* be. Inside the rear quarter panels (on a GTS), are some vents. They are made to allow the air to get out of the car if all the windows are up and the air bags go off. They vent out into those slits on either side of your tail lights. The vents, which are quite large, are covered with a thin rubber sheet, which is glued on. As a GTS is traveling down the road, a lot of air comes back to the tail of the car (ever notice how dirty your rear bumper gets after driving?). It could be that the rubber covers that are glued onto the vents have come loose and are allowing the exhaust gas to be drawn up into the passenger compartment. Might be worth looking into. You may be able to access them well enough through the rear hatch area, by pulling the carpet away at the outermost ends (near the amp you'll see the mesh area in the carpet on the drivers side, the carpet is not glued). Otherwise, it takes removing the rear tail light closure panel and looking up inside behind the quarter panel to see if they're still sealed. Just a thought.

Sean

 

[BlackACR]

I have the Mopar PCM that everyone seems to dislike. My air fuel is around 11.9 at 5000rpms. My Viper with no cats dynod 425rwh 471rwt. SAE corrected. So, it seems to be working for me great. Not to bad for a cream puff!!!

 

[TacDoc]

The exhaust contains CARBON MONOXIDE. If you sre getting a dose of this it could give give you you a headache. If really curious, next time you drive the car and get your headache, swing by an ER and get an ABG with CO level done. An abnormal high result would support the exhaust fumes as a cause.

 

[Butch The Snake]

AB,

I have Bellenger headers with 3" Bellenger exhaust (no cats, no mufflers), excellent sound and yes the exhaust smells when it was new. After a 100 miles or so the smell will be gone.