i have a dodge ram 1500 v8 5.2l, and im thinkin bout puttin straight pipes on it but i personally dont know enough about them to make the decision yet. first off i plan on cutting off the muffler but leaving the cat on so keep that in mind. But i have been reading about sometimes straight pipes give better mpg and also more rpm's, but what about that back pressure? if i leave the cats on would it still provide enough? and also what size pipe should i use? and advice would be appreciated or any website explaining that stuff. thanks

 

Welcome to DF erb! First off so I can get ya pointed in the right direction, what year Ram do you own? Maybe the Ram owners can give ya a better outlook

Personally I like the SI-SO or SI-DO (Catback). Either way you will make the engine breather better, thus the idea of better MPGs. Backpressure should not bother your engine because the computer will adjust for it. Also note that with the loss of back pressure you might notice a loss of lower end torque, because its moved in the higher rpm range. Now older carb motors, that was a different story with a loss of back pressure. As for Pipe Size I dont think I would go bigger than 3". I am running this on my 4.7 with a SI-SO Cherry Bomb Pro and I like it.

 

its a 97 with well over 200k miles on it
yeah, is there any cheap ways to do it?

 

Lots actually. With the 5.2 many people stick with a 2.5" pipe, but I wouldn't go any bigger than a 3".
If your looking for cheap, the best way I've found is to cut off the muffler, remove the tail-pipe, and the put a turn down tip on right onto the pipe coming off the cat. Now, that's the cheapest it gets. However, it's also very very very loud. Your cutting the muffler right off behind the cab, so all the sound and vibration will be coming straight up to the cab. Your gonna have to get used to yellin' at your buddies when riding around.

There are other alternative as well. You can get a cheap glasspack online For $20, cut the muffler off and then put on the glass pack and slap a turn down on the glasspack exit. This will move the exhaust down on your truck, making it a little less noisy in the cab, but still provide a nice deep tone.

If my memory serves me correctly, there is a muffler on the factory exhaust as well as a resonator in the tailpipe. When I had my 96, I chose the first method I explained. Nothing beats it. I consider it to be a "natural" sound. So if you choose to keep the factory exit point, you'd going to have to cut out the resonator. I find this to be a major pain in the *** because there is a turn in the res. I would say screw the factory tail pipe all together and just have a pipe made in the same shape from a muffler shop and use that.

Oh, and your factory piping is a 2.5"

 

10-4
well i was thinkin an what if i just cut out the muffler and replace it with a piece of exhaust pipe, then towards the end where it bends to come out the side cut it off before the turn and replace that with a straight piece so it comes out under the bumper. Then coming off the other manifold have just pipe, no cat or muffler and run it out the bumper. Would that work or would it sound retarded?

Actually i suppose i would have to put something on it to get back pressure.

 

Well, it would work yes. You will loose a lot of your low end torque though. And it would also be about as loud as it gets. And depending on where you live, removing the cats may be illegal. For example, I live in NY, and if your car came with a factory cat you have to have it on and it must be functional to pass NYS inspection.

If your really not sure what you want to do, then start simple. Start with the muffler. Take it off put a pipe in and take the res out of the tail pipe and put a pipe in. If your not happy with that, search your local laws about removing the cats and if you aloud to go for it. Just be aware that the low end power will shift to a higher RPM. Always start with something that can be replaced easily. That way if you end up not liking it, it's not big deal. You can just put it back on.

 

thats true, yeah i live in lakeland florida ha
how do i take the res out. i know what it is but i dont know where or how to get to it.

 

The res is in the tail pipe. Get under your truck behind the rear axle and you'll see where it is. It's a larger part of the pipe and it's got a bend in it. Cutting it off would be possible, but putting another pipe on, I'm not sure about. If your not sure, take a picture of your muffler, then the pipe coming out of your muffler going over top of the axle, and then a picture of the pipe coming over top fo the axle and out the side. I'll try and pin point it for you.

here's a quick drawing. Not sure if this is the right tail pipe or not, but it doesn't matter. I drew where it goes over the axle, and in the blue circle with the arrow is about where your res should be.

 

yeah, i went out and looked at it, that drawing helped me find it thanks
i'm a pretty good welder and got all the equipment to bend and weld but just dont have the mechanical knowledge

 

You really don't need mechanical know-how to cut out a muffler and a res. You've got the welding down, one thing I don't have, and you can bend a pipe. Your already better off than I am.

Like I said, if your looking for cheap, loud and good flow just straight pipe it after the cat meaning cut the muffler and res out. I think you'll be pleasantly surprised by the affects. I know I was the first time I did it.