I'm wantin to put dual exhaust on my '05 1500 Hemi.I was told that I could go with a one in/two out from the muffler and save the cost of 2 cats.Myself I'd like to go from the manifold and run 2 separate pipes.The first idea seems to be a makeshift dual system where the second is naturally the real deal.What,if any,are the pro and cons of the one in/two out if anyone knows.Will either plan maybe give me valve problems from compression ratio changes?Thanx for ya'lls help/advice.

 

I honestly cant tell the power difference between true duals and a single in/ dual out muffler system. There may be a slight sound difference. As long as your not using chambered muffler/s then both system work great. I dont know about valve problems or at least I dont think i have heard anyone having valve problems from exhaust. I would at least keep the cats on just to give a little back pressure. The stock cats are high flow cats anyhow and dont hurt a thing.

 

Why would you want backpressure though? I was always under the assumption that it was a bad thing. Well, with v8's anyway. 4cyl engines require backpressure to perform at their peak. v8's on the other hand need to breath more freely. http://en.wikipedia.org/wiki/Back_pressure

 

Back pressure is an incorrect term, but you get the general idea.

If your pipe(s) is/are to large, the exhaust gasses will cool before they exit the pipe. That means your engine has to push out colder, denser exhaust, which is bad.

I'll move this over to the 3rd gen section for you, get some more opinions/comments.

 

Changing your exhaust is not going to give you any valve issues or change compression ratios.

Ive got Pacesetter LTs, no cats, x pipe, dual DMH cutouts, dual Magnaflows and dual 4" tips.

So if you want something like that then there is it and it can be done. However it is not cheap as compared to a catback (SIDO) exhaust like you are talking about. Ive got about $1100 in that total.

My first exh setup was with a SIDO FLowmaster Delta 40 with a single DMH cutout and 4" tips. I bought all the hardware online and had a shop weld it all together for 150+350 in parts

 

The above statement about a V8 not needing backpressure is absolutely incorrect. Without backpressure you lose a bunch of torque. High end flows better, but it really suffers on the low end.

As for true dual vs SIDO mufflers. When done correctly, SIDO should have a 3" inlet to the muffler, and true dual should have 2.5". There IS more air moving through the true dual, but not enough to warrant spending the extra money IMO. What muffler you choose will have more effect than true dual vs sido.

 

I have a 2006 Ram regular cab with the 5.7. I use BBK shorty headers( easy to install) run them through magnaflow hi flo spun convertors, then the two pipes go to a dual in dual out magnaflow muffler then two 2 1/2 inch tailpipes. As it sits, on the dyno it makes 300 rwhp and 400 lbs ft of torque. The shortys help build torque which is what a heavy truck needs to get moving

 

If you want to run two pipes, just use a dido muffler. All manufacturers make them

 

The general rule I've always read about is that shorties are good for high end and long tubes are good for low end torque which is what a truck needs to get moving. But as for the OP I would say unless you plan doing some real performance mods it's not worth the extra money for true duals and you would be happy and so would your wallet for going with a SIDO

 

sido example, cherry bomb extreme-$72 shipped to my door in three days plus 15 bucks for down turns. sounds nice and was cheap. ditto on what 08hemi says about the wallet being happy