I have a stock 1996 5.9L RAM 4x4 with the exception of a Mopar chip.
I'd like to put dual exhaust with headers on it, and I don't want a lot of
sound from the mufflers since it is my daily driver. I also need it to pass
emmissions in Atlanta.
Anyone have any suggestions for a good system? I don't mind spending a
little extra for the right setup.
I assumed I would need two cat converters and two pairs of O2 sensors?
Don't know how the O2 thing would work...
yes it could be a problem. your particualr engine requires a certain amount
of back pressure from the exhaust system to funtion properly. when you
increase flow through the exhaust a general rule is that you gain top end
horse power and lose low end torque. remember the old adage, give and take.
once you hit the point of dimenishing returns, you lose so much torque that
you will see a significant decrease in bottom end performance.
on an engine that has been hotrodded with heads, cams and higher compression
ratios you need to get a good bit more flow to maximize these alterations
but on a mostly stock motor you can flow the motor too much.
we had a guy recently complaining about how he had put a new high flow
exhaust system on a 2001 ram with a 360 and it wouldn't hardly roll off the
line. my wrench went out and crawled under it and then told the guy to take
it for a drive. the guy came back grinning like a monkey and was very
happy. he said it was like a new truck and asked what the wrench had done.
the trick was he had taken a big pair of channel locks and squeezed the
exhaust pipe about half way compressed. this increased the back pressure
and fixed the problem.
my wrench then told the dude to fix it right, he needed to go put his
original exhaust manifolds and catalytic converters back on and use only the
portion of the new exhaust system that is behind the cat. this guy got mad
and cussed us out. that couldn't be the problem, he said, and he continued
by saying that they had already discarded of the factory parts. he was very
mad because the *book* had said the new exhaust would be better and we
couldn't know more than the *book*. but the proof is in the pudding.
so if you are going to add a cam and do head work i would suggest a
completly new free flowing system. if all you have is a performance chip on
a stock motor then buy a good cat-back sysem and leave the forward stuff
Good info - thanks. The last time I did such a thing, it was on a '71 340
but it worked great. But that was in the days of 10.5-to-1 compression, big
valves with a huge Thermoquad. No emmisions to be concerned with either :-)
(Of course it came with duals, but headers were added.)
What you're asking for is not possible.
Federal emission regs require you to maintain the
same exhasut configuration from the engine through the
cats. You can change parts and make improvements with
emissions legal parts. But you can not change the
configuration. There is no emissions legal true dual
And practically speaking, you don't need to.
Unless you reguarly run the engine to 5,000+, you won't
ever get the advantage of true duals anyway. They gain
HP at the top end, but cost you torque on the bottom end.
What you really want is a good set of equal length
shorty headers, a bigger Y pipe, a performance cat (or
three), a 3 inch single pipe, and the biggest muffler
you can fit under there.
If you're lucky, you'll gain 15-20 ft/lbs. It
will cost you pretty close to a grand. More if you
hire a shop to do it for you.
Good info - thanks. I've never modified a post-1971 stock motor, so this
I've been looking at Cobra's in recent years as well. Do you have pics of
yours on-line? I think I've settled on Superformance but they just got more
$$$ with Shelby settling with them. And I'm 6'5" so that is a concern
Here a picture of my car, and some of the specs. I
think the only thing I changed was the brakes. I'm now
using some huge Wilwood brakes.
Here's some other pictures I've taken over the years
since I started building it.
The superformance is a good car. The build quality is
excellent. But it's a bit heavier than other Cobra's;
and it's very expensive. I think their price just went
up to around $79K for a roller; but that could be just
a vicious rumer.
Here are two good sites to get more information about
FFR's and other Cobra kits:
If you want a good car, and don't want to build it
yourself, consider a pro building a FFR for you to your
specs. Might even be cheaper than a Superformance.
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