I am thinking about upgrading to a 4" or 5" exhaust. From what I've read there is no real advantage with going with the 5", right? I've been looking at the MBRP system. Where does the exhaust hook into, manifold? Is the noise higher with the MBRP muffler than the factory muffler? Also, does my 2000 PSD F-250 have a catalytic converter? If so, how is it incorporated into the exhaust system?

Thanks, Chad

 

Only advantage to a 5" system with a near stock engine is aesthetic - sound and looks. I have a 5" and wouldn't exchange it for a 4".

If you have a cat, then it is a 3.5" in/out and won't fit in a 4" system. So the questions are:
1 - Do you have to keep the cat for smog inspections? If not, then don't worry about it. If yes, then:
2 - does anyone here know of a 4" cat to replace the stock one?

If you have to keep the stock cat and so, must stick with a 3.5" system, there are still improvements that can be made, ranging from cheap to as much as buying a whole system.

Cheapest - remove the muffler and run a straight pipe. Some people love the way it sounds, but it is louder. Need a muffler? Try a Walker BTM (about $50). It is a straight-through muffler that significantly reduces backpressure (and lowers EGT) compared to the stock POS restrictive muffler.

Expensive - the stock downpipe may not be 3.5" all the way. Some I've seen neck down a bit to give more clearance. You can replace the DP with a good 3.5" (probably $100 to $150). Also, Aeroturbine now makes a 3.5" version of their muffler, which is supposed to work better (better muffling, less backpressure, lower EGT) than any other muffler design (about $250).

How much better will the Aeroturbine and new DP be over the BTM? Um, I don't know. I would guess better, but not as good as a 4" - BUT the Aeroturbine is supposed to eliminate the dreaded drone, a problem that some people report with the BTM and straight pipes.

If I had to stick with a 3.5", I'd probably go with the Aeroturbine, but forget the DP - too much money for too little benefit.

 

Exactly, except I had the Aeroturbine 4040 welded onto the stock 3.5 in system. It made a difference in overall noise and power, enough to make me wish I had done it sooner. What I wanted was the temporary benefit of a 4in. system without having to buy a whole new set of pipes. I got what I needed because my power, mileage, and overall growl went up as a result. I didn't quite know what I was buying when I bought this muffler though. Now I have the best muffler for lowering EGTs on the 4 in. MBRP system I'm getting. It'll reduce my EGTs even more when either stacked with another muffler or by itself. Give Gillett Diesel Service a call at 801-571-7780 they'll tell you everything you need to know about it. They tested it and probably know more about it than anyone out there.