Dodge Magnum RT Hemi: Exhaust question

I would first recommend checking your state smog laws. If there are no statements about altering the exhaust system then it should be okay. As far as what to do, I'll leave that recommendation to someone else.

You might also wish to check the federal smog laws: it's illegal to make that modification (as I learned when I wanted to switch my '78 Newport to duals). The shop I was talking to had disovered, to $12,000 of their chagrin, that the EPA does spot-check shops for making illegal modifications, even in states like mine that have no laws against it.

A lot of people around here (Kokomo, IN) take the mufflers off their Ram pickups with the new hemi and they seem to run ok. As long as the fuel system will keep the fuel/air mixure within the proper range, performance will not change significantly. There seem to be few legal implications for doing exhaust system mods in Indiana, as long as the catalytic converter stays in place.

Wait until the rumored Srt8 version comes out. It's supposed to have a more aggresive exhaust system. Order it and put it on yours...

Geeze, I knew I hated Kokomo for more reasons then just all the freakin' stop lights!

me-not-you

I've wondered about that myself. I HATE Flowbastards on most any car, but using a pair of Dynomax mufflers might produce a nice sound. The danger is that it might also sound HORRIBLE when operating in 4-cylinder mode cruising down the highway- like a high-school kid's riced-out Honda

4-cylinder with a "fart pipe" exhaust :-p

In every state that I'm aware of, you are free to modify the exhaust system from the catlyst backward, provided that you keep the ORIGINAL catalyst in the ORIGINAL location, with no changes whatsoever from the catalyst forward to the engine, and that the exhaust final discharge is in or very near the original location. That would, of course, include keeping any O2 sensor downstream from the catalyst in its original location, but they're usually located right at the catalyst outlet.

And with the stir the Magnum is making, I'll bet you anything that there will be some CARB-approved (legal) cat-forward modifications (headers, bigger downpipes, computers, camshaft, intake manifold, cylinder heads etc.) from Mopar Performance or other vendors in a few years, just as there are for the Ram pickups and for GM F-bodies, Ford Mustangs, etc.

But the only reason (IIRC) that was a violation is because the car was originally equipped with a SINGLE catalyst, and converting it to duals necessarily alters the original catalyst location and the plumbing forward from the catalyst. The very nice thing about the Magnum (and the Ram trucks with the Hemi, and the Durango) is that they already have dual catalysts and the exhaust either remains dual or combines to a single muffler AFTER the catalysts. Leave those catalysts alone, and I'm pretty sure you can hang a complete new muffler system behind them.

It would be in four cylinder mode only under very low load conditions and at lowish rpm, so it might sound more like an old Farmall tractor.

That's why I suggested checking smog/pollution laws. I live in the greater Los Angeles area where we are used to not being able to do much in the way of tampering with exhaust/emission systems. Of course there aren't many things I have wanted to do with the vehicles I own so I have never really checked in to it, but each month when the JCWhitney catalog arrives and I browse through it with the remote possibility they have something I really want, I do manage to notice the "not legal for sale in California" on certain items. :-(

What i said above is (or at least was until recently) true of the People's Republic of Kalifornia also.

In fact, you can put headers, new aluminum cylinder heads, a new intake manifold, a different cam, different ratio rocker arms, a performance muffler, performance computer, and bigger tailpipe on a 5.9L powered Dodge Ram pickup and still be legal even in LA. You just have to use the parts that have CARB approval numbers- available from Mopar Performance and others. I don't think MP has much (if anything) available for the Hemi yet (which is one of the reasons why modified 5.9 trucks are still MUCH faster than Hemi trucks), but even if MP doesn't come out with CARB-numbered and approved parts for the Hemi, SOMEONE will.

Which is much better than a Honda with a coffee-can exhaust... but could still be annoying when you're cruising down the highway.

Ideally, I'd like to HEAR the exhaust rumble when the engine is working hard, and then maybe hear just a remote, muted, soft burble cruising down the highway under light load. I hate hearing a constant drone from the exhaust on the highway.

........but it won't make much sense on a '04 Pacifica, '96 T&C LXi, '93 GC Laredo (6), or a '91 Accord LX Coupe!!!

When warmed up, does the hemi in the Magnum and 300 idle on 4 cylinders or 8? If it idles on 4, the one octace uptake in exhaust note when accelerating from a stop should be interesting with a loud exhaust.

Agreed, but do you have any IDEA what kind of performance stuff you can actually get for that Accord? Or the Grand Cherokee, for that matter.

Sounds like a job for noise-cancelling technology.

--Geoff

Oh yes - I do know of all the performance stuff available for both. However, the Accord is being driven by my 19 year old son and the Grand Cherokee by my

17 year old daughter. The middle of next month we move them up to San Luis Obispo for college so I don't even want to think of performance stuff!!! ;-) My son has enetertained the thought of submitting an entry to "Pimp My Auto" (or whatever the name of that show is) and my daughter has asked a few questions about off-roading - - and they both wonder why my hair is turning gray!!!!!!!

Performance stuff for an Accord? What's the point? :-)

Matt

Wasting a lot of money, as far as I can tell :-) But it IS available....