AC Cobra exhaust noise and fumes

mnjts@aol.com · #1 (**permalink**) 10-08-2012, 09:46 PM

Hello,

I have had a Ford 392 AC Cobra.

I am discovering that I have some pretty strong fumes at idle.

Additionally, I want to quiet the car down as much as possible which was always the plan when I bought it.

Any suggestions and anybody install catalic converters.

Jimmy
562.879.2298

ERA Chas · #2 (**permalink**) 10-09-2012, 06:59 AM

You've got this all wrong Jimmy. Sell the car and buy a Miata. Cat converters is what forced many of us to buy / build Cobras.
Seriously-that comes with the territory with Cobras-you've made a poor choice if those are your priorities..

FWB · #3 (**permalink**) 10-09-2012, 07:18 AM

Quote:

Originally Posted by mnjts@aol.com

Hello,

I have had a Ford 392 AC Cobra.

I am discovering that I have some pretty strong fumes at idle.

Additionally, I want to quiet the car down as much as possible which was always the plan when I bought it.

Any suggestions and anybody install catalic converters.

Jimmy
562.879.2298

i think i just vomited in my mouth a little....
chances are the cats will make the car not even idle from the restriction.

tboneheller · #4 (**permalink**) 10-09-2012, 07:42 AM

If you install some 90* bends on the sidepipes, you can turn them into stacks. That should reduce some of the fumes that you are experiencing.

NFLDMNBB · #5 (**permalink**) 10-09-2012, 07:48 AM

Use racing fuel; instead of trying to get rid of the fumes you will become addicted!

FWB · #6 (**permalink**) 10-09-2012, 07:52 AM

these are both functional and stylish.....

D-CEL · #7 (**permalink**) 10-09-2012, 08:16 AM

Jimmy,

A rich idle is easily fixed with a little tuning. I would take the car to Randy Ritchey at Performance Associates in San Dimas. He is one of the best carb guys in California.

Performance Associates

As far as the catalytic converter comment.

Dude!! Your killin me! Cut it out..

Get some ear plugs and call it a day.

Jason

flaflier · #8 (**permalink**) 10-09-2012, 08:55 AM

D-CEL · #9 (**permalink**) 10-09-2012, 08:58 AM

LOL!!

I was trying to be nice...lol

bran3b · #10 (**permalink**) 10-09-2012, 09:23 AM

There are muffler inserts that you may be able to install, Car Chemistry 3DI03R - Car Chemistry Exhaust Inserts - Overview - SummitRacing.com and if your turnouts are removable you may be able to redirect the exhaust to exit under the car, or at least down which may make the noise more tolerable. I have never tried either solution so these are just ideas, your results may vary...

tirod · #11 (**permalink**) 10-09-2012, 09:36 AM

The problem is most Cobra replicars emulate the S/C 427 layout with sidepipes. Most Shelby's sold were undercar exhaust, and there is a reason for that.

Sidepipes are loud and smelly, it's no problem racing. Idling thru Taco Bell, yes. Most cars on the road are built with undercar exhaust with tips out back where the aerodynamics won't suck it back over the trunk into your face.

Side exhaust, not so much. It's right there in your ears, and the fumes at your elbow, literally. But the Manly Men crowd thinks that's cool, and builds them that way. No reason they should look to reality or the fact very few original Cobra buyers wanted that. In fact, the loud smelly sidepipes were part of the problem, it took two years to sell the last 427, and Shelby closed it's doors after that.

As a daily driver, sidepipes don't cut it. And the guys jerking you around on this thread agree, too, just look at their stable of cars they and their family drive to work. The Cobra in the garage is the exception.

Undercar exhaust was the answer then, and still is. Ignore the chest thumping and take a long look at the originals at a show near you. It cleans up the boy toy wannabe racer look and turns it into a mature man's car. You don't have to suffer, neither do your passengers, and it goes just as fast on city streets.

There's plenty of ways to do it, this one handles a lot of issues well: Under Car Exhaust - Part 1

AKA EDDY · #12 (**permalink**) 10-09-2012, 09:51 AM

As ERA Chase said, sell the car and buy a Miata.

ACademic · #13 (**permalink**) 10-09-2012, 09:54 AM

Quote:

Originally Posted by tirod

Sidepipes are loud and smelly, it's no problem racing. Idling thru Taco Bell, yes. Most cars on the road are built with undercar exhaust with tips out back where the aerodynamics won't suck it back over the trunk into your face.

Side exhaust, not so much. It's right there in your ears, and the fumes at your elbow, literally. But the Manly Men crowd thinks that's cool, and builds them that way. No reason they should look to reality or the fact very few original Cobra buyers wanted that. In fact, the loud smelly sidepipes were part of the problem, it took two years to sell the last 427, and Shelby closed it's doors after that.

As a daily driver, sidepipes don't cut it. And the guys jerking you around on this thread agree, too, just look at their stable of cars they and their family drive to work. The Cobra in the garage is the exception.

Undercar exhaust was the answer then, and still is. Ignore the chest thumping and take a long look at the originals at a show near you. It cleans up the boy toy wannabe racer look and turns it into a mature man's car. You don't have to suffer, neither do your passengers, and it goes just as fast on city streets.

There's an insult to virtually every member of CC in here somewhere.

JST4FUN · #14 (**permalink**) 10-09-2012, 12:28 PM

Man, I thought this must be a late April fools joke. If it isn't, it is clearly Miata time!

rodneym · #15 (**permalink**) 10-09-2012, 12:38 PM

Quote:

Originally Posted by tirod

...and turns it into a mature man's car.

God, please, no!

Rick Parker · #16 (**permalink**) 10-09-2012, 01:48 PM

Your jetting may be overly rich resulting in high unburnt hydrocarbons, it'll really burn your eyes.

CSX3183 · #17 (**permalink**) 10-09-2012, 02:35 PM

I really can't add much to the majority of comments, without geeting rude.

You are in the wrong hobby, have no idea what you're doing, and frankly, you sound like a government experiment that went bad!

Thor maine · #18 (**permalink**) 10-09-2012, 02:41 PM

For the fumes getting a tune will probably do the trick or go to fuel injection. I am thinking of doing a dual system . An electric cutout just past the muffler in the side pipe that would go to a turbo muffler and exit out the back. Nice and quite when I want it or to draw less attention from the boy's in blue and at the flip of a switch ROCK AND ROLL BABY. Now if I can just work it out???

SunDude · #19 (**permalink**) 10-09-2012, 02:45 PM

Yeeesh, poor Jimmy...I don't imagine he expected this kind of response when he posted his question. Wonder if he'll ever be back.

But it also sounds to me as though Jimmy bought the wrong car. He might've been much happier had he bought one with undercar exhaust and a more modern powerplant, such as a Coyote 5.0-litre. Buying one with a Ford Racing 392 and side pipes, then converting it to what he should've bought in the first place, sounds like a lot of effort and moolah.

Not sure how he could've bought one without realizing it was loud and smelly. Heck, my Cobra doesn't even have to be running to smell like gas fumes. Just opening the garage door is enough to release a heady aroma. But the difference is, I wouldn't have it any other way.

FWB · #20 (**permalink**) 10-09-2012, 02:54 PM

i hope he comes back.....we are all just having our fun, at his expense of course, there are times when i putt by a 80 year old woman that i am rather taken back by blowing her off the sidewalk beside me. but i figure thats life....
jimmy should embrace his sidepipes and realize how much fun he can have by driving down a residential street with cars parked and set off every single car alarm as he goes by......