Exhaust confusion - Diesel Forum

n2dx · 10-23-2009, 03:43 PM

I have been digging around trying to find exhaust parts online. All the ads pop up with upgrading, etc to big diameter systems... So, my question is, starting at the turbo all the way back, do we have the same size piping? Or does it change along the way? What size?

Thanks

aklim · 10-23-2009, 03:57 PM

I would do it once and do it right. You can simply replace the muffler to a BTM unit but all you have done is move the choke point to the downpipe. You can get a 5 in system but your downpipe will still be 4 in because little more can fit in there without some real work. I am happy with my 4 in MBRP which goes from the turbo back and is 4 inches. It lowers the EGT because of the lower restriction in the downipie when it goes from a stock unit to 4 in mandrel bent.

TXANGLER · 10-23-2009, 07:39 PM

I give you the "other side" of aklim. Not bashing anyones opinion ever.
OEM is a 3" downpipe to 3 1/2" exhaust. The greatest restriction is the OE muffler. For $75 installed the Walker 21470 you cure 75% of the issues. If I am not mistaken the MBRP has a 3 1/2" Downpipe which gains a little flow but sacarifices a little low end torque. You can easily use the $300 on tunes and an intake etc etc. The best egt drop I have witnessed on a BTM to 4" conversion is about 100 degrees max.This was on a digital gauge setup, 7.3 F250. The owner still wishes he would have spent the $ elsewhere (ie. better tunes).
Good luck either way

BoilermakerSteve · 10-23-2009, 10:26 PM

My MBRP system is 4" from the turbo back. It is a really tight fit, but it does fit.

steve

n2dx · 10-24-2009, 12:46 AM

Thanks for the info about sizes. I ran across an issue in my digging around by accident that talks about the seals in the exhaust pipe up near the turbo/downpipe area where they can due to flexing, etc. have small leaks. Is this a 6.0 problem as well?

MotionMan · 10-24-2009, 06:48 AM

Also remember the X is enclosed, unlike a PU so the drone inside can drive you out. I like the BTM option, if I were to do anything I would try that too.

leoneo01 · 10-24-2009, 10:00 AM

Does anyone with a 4" downpipe have issues with the exhaust and trans dip stick touching?

TXANGLER · 10-24-2009, 10:53 AM

Quote:

Originally Posted by n2dx

Thanks for the info about sizes. I ran across an issue in my digging around by accident that talks about the seals in the exhaust pipe up near the turbo/downpipe area where they can due to flexing, etc. have small leaks. Is this a 6.0 problem as well?

I dont think the 6.0 have up pipe leaks like the 7.3. Mine has been leaking for 2 yrs but its a small leak.

**Beast** · 10-24-2009, 11:27 AM

I have the 4" maganflow with 3.5"downpipe my drone with the chip under load was too much. I just put back on a new OEM system. Quieter but some drone under load with programmer. Weird. Anyway, I don't push it as much anymore due to cost of fuel so backing off a little due to temp is OK with me. I don't think it makes much difference with mpgs. Go with BTM first. Of course I now have two good exhaust systems a 4" Maganaflow with a flex pipe and a new OEM system.

aklim · 10-24-2009, 12:59 PM

Quote:

Originally Posted by leoneo01

Does anyone with a 4" downpipe have issues with the exhaust and trans dip stick touching?

Not with my MBRP.

Bruce1954 · 10-24-2009, 08:54 PM

Quote:

Originally Posted by Beast

I have the 4" maganflow with 3.5"downpipe my drone with the chip under load was too much. I just put back on a new OEM system. Quieter but some drone under load with programmer. Weird. Anyway, I don't push it as much anymore due to cost of fuel so backing off a little due to temp is OK with me. I don't think it makes much difference with mpgs. Go with BTM first. Of course I now have two good exhaust systems a 4" Maganaflow with a flex pipe and a new OEM system.

I have the Magnaflow as well and it was noisy with a bad drone then I added the cat back in it was so that the 4" pipes could be welded in and it solved the noise and greatly reduced the drone to only very high load conditions.

But I have a 6.0 with the cat so it is much different.

leoneo01 · 10-28-2009, 03:54 PM

Quote:

Originally Posted by aklim

Not with my MBRP.

Thanks for the reply. It sounds like i got a potential problem.

boertje · 10-28-2009, 09:51 PM

I have one of the early Banks systems before they came out with a 4" for the X. Mine is 3.5 turbo back and it seems to do quite well. I see no reason to spend the money to go with anything bigger.

scrmn6guns · 10-29-2009, 02:39 AM

I have the 4" magnaflow and have no clearence issues and better I have no drone issues.

Peace2Peep · 10-29-2009, 10:52 PM

From what I understand, the drone comes in when people eliminate the stock CAT. It seems that those who retained the stock cat had little or no drone issues...Feedback?