Engine/Transmission (1994 - 1998) 12 valve- MBRP exhaust

[MHalloran]

Any of you fellow 12 valvers install the MBRP 4" straight through exhaust system from Xtreme Diesel Performance? I'll need one before the winter & I'm considering theirs. If so, how does it sound? Run better? Thanks for any info.

 

[DWeaver]

Hey,



Put mine on about 4 months ago. The hardest part was getting the old exhaust system out. The new system went together better than I thought it would, which is nice for a change.



I like the sound, not as loud as some of the 5"s in town, but can rattle someones cage when they get a smoke signal. I did lose a little low end, the trade off is I now have a better high end.



MPG's was negligable.



No drone in cab at all. Crusing with the pass. side window down it will sing to you but you dont get blotted out by it.

 

[McCRam]

put mine on yesterday, it sounds great. Shiniest thing on the truck. Haven't had a chance to use it much yet though. If there is a drone, I haven't heard it yet. I'm hauling some cattle this weekend, Ill let you know happens. I saw a video link on the tdr that had audio of the mbrp exhaust might try a search.



ps I haven't noticed any change in performance with my butt dyno.

 

[tURBOdIEZEl]

i had a 4" MBRP system before i went with the stacks (kept the DP and the rest of the system is collecting dust :-laf ) exhaust sounded awesome when i had the complete system on...

 

[Mark Craig]

MHalloran,



You'll love it we have sold a zillion of them to 12 valve owners as it gets rid of the tail pipe hanger that collects all the mud and dirt etc at the end of the stock tail pipe. You will need a special bracket to mount it on a 12 valve, so it you have any questions on that call us.



Mark @ DPPI

 

[ANG012]

I have had mine on for about 8 mo. and it sounds great. I killed the cat at the same time and the turbo temp has dropped about 100 deg. throughout the temp range.

 

[sfelts]

I just installed a PMT 4". it sounds great better high end and little loss of low end power. The PMT has a little drone in it at 2300 RPM other that that it is a great system. Can't say what the MBRP is like.

I bought the PMT because of the price. have to get the 1998 rear hanger from dodge and bolt it to the frame to hang the tail pipe sounds like the same as the MBRP. O the PMT sings too good luck.

 

[J.BURCHFIELD]

When I put on a 4in Exh pipe and 4in straight thru muffler it was the first time I had heard the turbo whine when I floored it.

 

[I Buck]

Mbrp

I installed the 409 turbo back with the 5" tip. Got the rear hanger (it's a 1995) and had a friend weld the hanger to the frame to suport the tail pipe. I have the straight through muffler. On a stock cummins, it's a little louder, with some drone at 1100 to 1200 rpms when starting out, and a little drone at 2100 to 2200 rpms, about where I shift gears. EGT's are down about 100*, and it don't take long to idle down to 250* befor shut down. With the stock system, when I floored it, got some black smoke, with the 4" system, no smoke at all. It looks like I picked up about 1 MPG, only have about 1400miles on it. I installed it when I found rust on the back of the stock muffler, and rust at every bend on the stock tail pipe. Looked pretty bad, but when I got the stock system off, I found a lot of metal under the rust, was still good for a few years yet. Was looking for an excuse to get the after market exhaust system anyway, sure looks good! When I craw under my truck, I bring a rag to wipe those big shinny pipes down!!!!

Buck.

 

[Dave M]

I installed the same MRRP 4 inch T409 SS from xtremeDiesel.com. I kinda wish I spent the extra $$ and got the T304 but I still love it. The system bolted up easily to the stock hangers. The hardest part was removing the old exhaust. I thought I could get it apart but after breaking 3 screwdrivers I took a hacksaw to it (trust me... I would not recommend this method... it took a LOOONG time... . thats thick 16 gauge steel!). Do yourself a favor and get a sawzall with metal blades. Thats the preferred method. The stock exhaust pipes get crimped from the clamps and they will never slip apart again... . I know.



Also, If you ever want to remove it again in your lifetime replace the pipe type exhaust hangers with 4 inch SS band clamps (you'll need 3). Got mine from NAPA for $10 apiece. I had to readjust mine to raise my tailpipe later and I was glad I got the band clamps.



As was stated earlier, you'll need the 98. 5 and up style tailpipe hanger. It was a bugger for me to drill holes in the frame to bolt it on. Also the downpipe bolts that came with it did not fit mine so I re-used the old ones. Hit all the bolts and nuts with some liquid wrench or (my favorite) PB Blaster for a few days before... you won't be sorry. Bolt it all up loose and test fit everthing before you tighten it down.



I noticed a drone at about 2,000+ RPM but since I usually shift thru anyhow it is not bad. Wifey really likes the sound and it has picked up and got pepper also. You won't be sorry if you add a BHAF or high flow (I used AFE Stage I) air filter and get rid of the stock box. Then the turbo will really whistle... Gottta love that sound!



Dave

 

[RobNJ]

Mbrp

Hey,



Just wanted to say what a great website This is my first post. What a wealth of knowledge I gained spending countless hours looking through the boards. It was such an asset in helping me purchase my rig. I tell ya that Cummins is just like music to my ears, dont think I'll ever buy a gasser again



Anyway I just finished installing the MBRP 4" 409 system on my truck. Quaility is top notch. Everything fit perfect. Removing the stocker is tough if you want to save it. Otherwise a Millwaukee with a 8 inch 14tpi metal blade makes it a piece of cake. Just cut it out. Total time by myself installing was about an hour or two. I wrapped my downpipe with 15' of 2" Black Graphite Thermo Tech wrap for good measure. The 4" sits pretty close to the firewall and the Thermo Tech cuts down on heat in the engine bay and is good to 2000 deg ... cant hurt. I had great results with it on my Grand National. I used the regular clamps. Apply some anti seize the the outside of the pipes and all the bolts. Helps a great deal if you ever want to take it off. Band Clamps would be another option. If you use the clamps that come with the system install them just past the slits in the pipes. Learned the hard way and installed them over the slits and had some leaks. No leaks now. For a standard cab long bed cut the extension pipe to 37" and the fitment is spot on. I also came up with a cheap way to hang the tailpipe that is rock solid. Get some turnbuckles with eyelets and some bots. Drill a hole in the bed crossmember hang one there and bolt the other one to the hole in the frame. Put some rubber fuel hose over the hangers that are already on the system so you dont get rattles. Sorry I did'nt pay attention to sizes I just went by eye but I'll enclose a pic. Came out great.

Sound on the system is awesome I love it. Not that much louder but definetly deeper. Sounds like a peterbilt Did not notice any drone but if you do you won't care it sounds so mean.

EGT's dropped about 100 deg and I picked up 4lbs of boost.

 

[McCRam]

After installing the system, I put on 500 miles towing a 8000 lbs trailer for half of them. I still haven't seen a performance change. I did get some great mileage on this trip though. I averaged 18 including the towing miles. I usually count on that type of mileage empty. It could be a fluke, you can't really figure a mileage change after only one tankful. I hope that this type of mileage contes though. I still like the system. It sounds great. I can hear the exhaust much clearer than stock, but I have not noticed a drone like others have.

 

[McCRam]

I've put on another 1000 miles on since I put the system on. My peak egts have dropped about 150 degrees when compared to the stock exhaust. Cool down time for the turbo is quicker as well. Mpg's seem to be up still as well.

 

[pwerwagn]

I had great results with it on my Grand National.

hey rob, welcome to the board.

there is another member here, wicked6, from NM that is a GN nut too.



--Jeff

 

[The patriot]

Another former GN owner here.

I really miss that car. 12 second commuter with full power.

Eric