Attention: TDR Forum Junkies 
Thought I'd share my first hand experience with today's installation of an 04. 5 elbow & downpipe, middle pipe (cat delete section if it was an 600 CTD), and the MBRP muffler/offset - all 4" - and connected to my original 4" tailpipe. Tomeygun supplied the "kit" and at his recommendation, I opted for the stainless steel band clamps - an option that I highly recommend. The end result is a super clean installation, strong, and can be disassembled for the next mod - which surely there will be other mods (i. e. , new turbo and downpipe). Tom certainly has hands-on experience with the 305/555 configuration and is an easy person to talk to.
Everything fits nicely, a sign of good engineering. The MBRP must weight 25 pounds less than the huge stock muffler. You can not appreciate the difference in size 4" makes over 3. 5" until you put the 04. 5 ebow next to the stock one, or the 04. 5 downpipe next to the seemingly tiny 3. 5" original one. No daylight show through the monster stock muffler but you can drop a softball straight through the MBRP. The MBRP muffler/offset pipe uses the stock hangers/rubber mounts and fits up nicely to the 4" original tailpipe. I cut the stock tailpipe right where it expands to 4" from the outlet of the stock muffler. I also cut off the original 3. 5" pipe going into the stock muffler just before the slip joint, saving the muffler from any damage.
OK, OK, everyone wants to know how it sounds... I was a little concerned that I would create a monster and have a LOUD truck. Not true. When I first started it up there was little change at idle. Blip the throttle and I noticed a little more "bite" to the exhaust. It was a bit crisper and very responsive. Driving it off like my grandmother, I was relieved that the noise level seemed unchanged, at least so close to stock that any difference was minimal. Once up to temperature I began to play a little and found a very civilized sound until I got serious, then a healty, muscular sound was revealed - but not obnoxious.
I took it on the Interstate and under light throttle I could not tell any difference again. Getting on it pretty good brought on the nice sound again. I did not experience any drone, but that test will be later when I hook up and pull the trailer. From what I can tell right now, I'm not really expecting a problem.
Also my EGT dropped 600°F, my ETs by 3 full seconds, and the paint is much more shiny!
No, I really don't expect too much performance wise, but the efficiency of the new system can not help but be improved. Visualy, the comparison of components is obvious to any engineer. If I get a 100°F drop in EGTs while pulling 15,000 pounds up a long hill, then it will be justifiable.
Actually, I can justify the expense on enjoying the sound alone...
Everything fits nicely, a sign of good engineering. The MBRP must weight 25 pounds less than the huge stock muffler. You can not appreciate the difference in size 4" makes over 3. 5" until you put the 04. 5 ebow next to the stock one, or the 04. 5 downpipe next to the seemingly tiny 3. 5" original one. No daylight show through the monster stock muffler but you can drop a softball straight through the MBRP. The MBRP muffler/offset pipe uses the stock hangers/rubber mounts and fits up nicely to the 4" original tailpipe. I cut the stock tailpipe right where it expands to 4" from the outlet of the stock muffler. I also cut off the original 3. 5" pipe going into the stock muffler just before the slip joint, saving the muffler from any damage.
OK, OK, everyone wants to know how it sounds... I was a little concerned that I would create a monster and have a LOUD truck. Not true. When I first started it up there was little change at idle. Blip the throttle and I noticed a little more "bite" to the exhaust. It was a bit crisper and very responsive. Driving it off like my grandmother, I was relieved that the noise level seemed unchanged, at least so close to stock that any difference was minimal. Once up to temperature I began to play a little and found a very civilized sound until I got serious, then a healty, muscular sound was revealed - but not obnoxious.
I took it on the Interstate and under light throttle I could not tell any difference again. Getting on it pretty good brought on the nice sound again. I did not experience any drone, but that test will be later when I hook up and pull the trailer. From what I can tell right now, I'm not really expecting a problem.
Also my EGT dropped 600°F, my ETs by 3 full seconds, and the paint is much more shiny!
No, I really don't expect too much performance wise, but the efficiency of the new system can not help but be improved. Visualy, the comparison of components is obvious to any engineer. If I get a 100°F drop in EGTs while pulling 15,000 pounds up a long hill, then it will be justifiable. Actually, I can justify the expense on enjoying the sound alone...
