Dodge Ram 1500 exhaust pipe size

Hey all, I’m new to this forum as a member but have been browsing it for some time now. Always find great topics and explanations here. My name is Dennis I’m from Eastern Pa and have a 2001 Dodge Ram 1500 4x4. The truck has a 408 stroker currently and is pushing about 470 or so crank HP. it might go up a bit after some future mods but I don’t think it will be north of 500 at all. I’m going to get a Dual exhaust Put on In 2 weeks. Right now I have long tube headers Into a 3” y-pipe, no cat, through a 3” single with a aero turbine muffler dumped out In front of the pass side Tire. I know this set up is choking it a bit. I have been up in the air as weather to go for a 2.5” or 3” dual system. I don’t race the truck and don’t hit really revs. It is a street truck and I sometimes tow 3000 pounds. My plan is for it to come off the headers, run parrallel on the pass Side into an x-pipe, Into Borla XR 1 mufflers and just have turn downs or come out the pass side again. Again, I was thinking 2.5” should be fine but I’m not sure. Anyone have any similar set ups or advice in 2.5” vs 3” dual system. Thanks again.

Welcome to the site, Dennis.

I have almost exactly the setup you are thinking of doing on my '01, I'll get you some pictures of how it's done, and give you an honest review later.

Dumping in front of the tire can cause serious deterioration of your wheels. all of the nasty stuff in the exhaust will cover that wheel and corrode the surface badly. The "NEW 1997" Fords dumped the exhaust in front of the right rear (probably saved them $5 per truck in pipe and bends). By '98 they had a Special Service Program to replace the pipes to dump behind the wheel, and they replaced A LOT of wheels that were etched...

If you wash religiously, you can prevent/delay it.

I don't know whether you want to hear this or not, but I hope you get something from my experience:

Stock 360 Magnum, '01 with 4.10's (Off-Road).

I scored a full, new-in-the-box Flowmaster dual exhaust with tips and 50 Series Single in/Dual out on Craigslist for $120.00. I had a local guy do the exhaust work. All this Fool had to do was join 2 pipes from the header to the mufflers, the rest was done for him as the Flowmaster pipes are mandrel bent, come with all the hangers and brackets and it fits perfect. The Flowmaster goes right from the bumper, over the axle and end about a foot ahead of the axle. Nope, he cried and whined that it was all wrong and he was going to do it his way ($$$$$$$) Long story short: it got done MY way. The 2 1/4" headpipes are joined to 2 1/2" pipes all the way to the back. I had him put an "H" pipe in. I've had my cat removed since day one.

Flowmaster

Prior to this I had read what the "experts" on here had to say and they insisted you need un-restricted flow to gain power, so, I went with a stainless steel pair of Magnaflow copies (appear similar to your XR1's) with a straight through design. What a MISTAKE that was. I previously had a Flowmaster 40 Single in/Single out that sounded amazing. I put these supposedly "deep rumble" things on my truck and it sounds AWFUL. I always got compliments on my Flowmaster sound and now the Hot Rod Dodge goes un-noticed and makes that typical "sputtering" sound that all the old V8 Dodges make. You know the one: that sound like someone spitting out a food wrapper after tearing it with their teeth or like the tailpipe is half under water.

So, with this true dual system having everything going for it maybe the sound will be all that's wrong with it? WRONG. Contrary to popular belief on here (and elsewhere) you DO need back pressure to build torque. I lost a significant amount of "lift-off" that a 5600 pound half-ton needs to get going. The power I lost got moved up to about 3700 rpm: Yep, that's right, exactly where 99% of the time a vehicle is never driven. Another downside was all the WEIGHT that extra pipe puts on a vehicle.

Given your usage description, the cubic inches, and horsepower, I think the 2.5's and a muffler with some back-pressure will be just about right for your engine if you want to maintain torque. As I said, I was expecting a moderate gain. I previously had a 318 2bbl in a First Gen and when I dualed it off with 2.5's and reverse-flow cans, the gain was noticable. Those straight-through "racing" cans I put on is causing the power loss, no doubt about it. One day I will cut that nonsense out of there and put a couple of Flowmaster 40's or 50's back in their place.


I took some pictures in the dark, not great, but you get the idea. I can do a sound clip for you ( I have the Flowmaster clip somewhere and can do a new one with this "straight-through" setup) if you want?

Thanks for the replies. Im not too worried about dumping in front of the tire for now. Its where it currently is. I may just put turn downs on the mufflers also. I really dont like going over the axle and out the back, Haven't decided yet but I do see your point. Right now I have an aeroturbine muffler on it and the truck is unbearable to listen to. I cant hold a conversation with my wife in the truck. if I was 16 I would have a stiffe but im 43 so im not digging it. Mine is an offroad edition also. I kind of already went in the wrong direction as far as power goes. The motor has a ton of power but it comes alive at around 2200 to 2400 rpm. I have a 2300 rpm stall converter that helps but once I hit Overdrive and the rpms drop below 2000, it falls on its face a bit unless I put a load on it to get it up in rpm. I may need to swap in 4.56 gears. I have 33" tires. I dont say the tune is the best. I feel the guy who tuned it is sub par. Im currently working with another tuner who is has an exceptional reputation across the board so Im interested to see how it performs after. My cam is not tremendous for a 408 but the motor does need to breathe. Im hoping that putting a 2.5" exhaust will give it some back pressure. I really like the sound of the borla exhaust. I had flow master and they did sound good but they rusted out. I was contemplating going with the aero turbine 2525 XL which is the quieter version of the one I have now. Its hard to find sound clips of a specific truck. Either way, at least I know im going with 2.5" now. Thanks again fellas

If you want to be able to have a conversation inside your truck then run the pipes out the back. My crew had side exit exhaust on it in front of the wheels and I hated it. Had a friend run two tail pipes for me and now the cab is drastically quieter. Still has plenty of wind and other noises but the exhaust noise is greatly reduced.