Skip to main content ↑ ↓
Topic: New Exhaust (Read 916 times) previous topic - next topic

New Exhaust

Well, it was my turn to put in a new Exhaust system.  I had Cummins in CLoverdale do it over the last couple days. I had a hole in the muffler and it would not pass VA state inspection so I needed to replace it. I used the same resonator that Dave M used but my set up is a bit different with the batteries right by the down pipe off the turbo. It took a full day to find the parts and piece it together.  Then we had to weld on new hangers and gussets too.  The tech took the completed piping home and tig welded it for a great tight fit and very few bands ( only two were used). I think the best thing I can say is it sounds a bit different but the performance is much much better. I have had Silverleaf for a long time now and I have usually seen my turbo pressure on full throttle pushing hard no higher than 27 to 28 but after the change out I hit 30.  I also merged onto I 81 on an uphill run where I never got above 45 prior at 57 and one big hill that slowed me to 55 was taken at 72 all the way.  THe other thing is I have always fun about 7.5 mpg on the way home up I 81.  It has been that as long as I did not hit traffic running the speed limit.  Today I ran 72 and finished up at 8.2 MPG.  That mileage difference will have to be checked over more miles but it was about 200 miles and a regular route I run all the time so I have records of the mileage for it over many trips. I will have to see when I fill up next how close I am but the Silver leaf is usually within a couple gallons on a 50 plus gallon fillup as long as I did not use the genny and I did not as it was only 60 degrees out.    So, I am very happy  with the improvements and I hope that I can run a few more miles soon and see the differences. 
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: New Exhaust

Reply #1 –
Quote from: John S –
Well, it was my turn to put in a new Exhaust system.  I had Cummins in CLoverdale do it

Is that the same Cummins shop that Dave M. used?  Not all Cummins shops are created equal - would be good to know which are recommended for the exhaust/resonator mod (I can tell the wheels are turning in Steve's brain after reading him your post  ;) )

-M
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: New Exhaust

Reply #2 –
Hmm. About 8% less fuel. At $0.50/mile +-, the would be a difference of about $0.04/mile. In 12,000 miles, that's about $480. That might be enough to pay for a big part of the modification.

Do the numbers make sense. (I just finished my evening wine. It makes everything I think or say seem profound, but my conclusions don't always make sense.  :) )
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: New Exhaust

Reply #3 –
Quote from: J. D. Stevens –
(... but my conclusions don't always make sense.  :) )
I modified my previous post to fix a few errors. (I should never post after enjoying the evening wine.  ;) )
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: New Exhaust

Reply #4 –
Michelle, I used the shop at Richmond, Va, for the Turbo setup, but for the exhaust work, that was done in my shop with help from another chap who can follow an idea.
This change John S. had done is the first step, it is a big/great step, I went further with the bypass turbo, the electronic waste gate control and of course the setup in the ECM for the change from the 450hp @ 1450 ft lb  to  the 500 hp @ 1550 FT LB.  it feels like about 200 hp jump.  With the 36' in the 30000 lb range, it goes real smartly.
Merry Merry Christmas

Re: New Exhaust

Reply #5 –
The cummins shop is in Cloverdale.  It is also on FT list of repair places.  They know FTs and have worked on a number of members coaches.  In fact they were talking to me about the coaches and I would say the persons name and they would say yes.  They remember the coach more than the person. Also, they knw FT coaches have access to work on so they schedule us like a truck while other brands, especially on freightliner chassis are pushed out a bit and only one a week is brought in.  They have to remove radiators and other time delaying things.  The newer coaches, even FT with the rear bath or the east west bed and small hatch are all pains to work on.  They said, on some coaches they disconnect the engine and lift the coach up then work on it then lower the coach.  Adds 16 hours to the bill.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: New Exhaust

Reply #6 –
Quote from: J. D. Stevens –
Hmm. About 8% less fuel. At $0.50/mile +-, the would be a difference of about $0.04/mile. In 12,000 miles, that's about $480. That might be enough to pay for a big part of the modification.

Do the numbers make sense. (I just finished my evening wine. It makes everything I think or say seem profound, but my conclusions don't always make sense.  :) )


I put on about 30,000 miles a year normally too.  It is amazing how this frees up the engine. Steve, you might already have 500hp in your coach already.  The issue I had was batteries and cables in the way.  Mine was one of the few years they stuck the start batteries in the rear with no boor to get to them on the drivers side. 
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: New Exhaust

Reply #7 –
The ISM500 did not appear until the 2004 model, however I would guess the later 2003 units might have had it.
One of the changes was adding the EGR to the 2002 units (I think) for sure in the 2003 units, along with the variable geometry turbo not the bypass type.
Opinion seems to indicate the V-G turbo can make more boost  as it is ECM controlled, so what ever program the ECM has determines the boost curve.
Since my setup is a comb of different setups, they were able to arrive with the desired results.  Was told it would be a STRONG 500 HP, I think they are right.
Now the down side, In truck applications at approx. one mil miles a block stiffener plate (Girdle) needs to be installed.  Trucks mostly do not go  much over 380 hp.  I had one installed before I found it really is not needed on a motor home type duty.  Also the EGR is the only weak link in the ISM engines, so pay attention to your power and smoke trail.
The ISM500 come with this plate installed I am told by Cummins. 
So as usual, FWIW

Re: New Exhaust

Reply #8 –
If I read the post correct on the awkward placing and access to work on exhaust--I will repeat myself and say why not remove the side panel as I did. It is a no brainer of a job and makes life so much easier.
John

ps. on my boost gauge and silverleaf I show 34 max.
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: New Exhaust

Reply #9 –
Quote from: Dave M –
The ISM500 did not appear until the 2004 model, however I would guess the later 2003 units might have had it.

I would have to guess ours is an early-to-mid 2003 - in-service date of September '02.  We wouldn't do the full hp upgrade, but the ROI of the exhaust portion of the mods sounds promising (not just in any potential fuel economy improvements, but also in less stress on the engine).

Quote from: Dave M –
for the exhaust work, that was done in my shop with help from another chap who can follow an idea.

Hmmmm.....  ;)

Anyone mind ballparking the cost of just the exhaust mod?

Quote from: J. D. Stevens –
I modified my previous post to fix a few errors. (I should never post after enjoying the evening wine.  ;) )

Posting is fine, it's moderating after a glass of wine that's to be avoided  ;)

Michelle
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: New Exhaust

Reply #10 –
Michelle, I did my own work and it was very easy. it cost approx $75 for the 4ft of stainless flex, resonator was around $80 and clamps $18 each (3) hangers $15, and I used the old tailpiece again as it was good. With my bad back it was 4 hrs from start to finish and too take off side panel and replace add another 1 1/2hrs. Alot easier than I was expecting. your 320 may be different than my 295
John H
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: New Exhaust

Reply #11 –
One point I had never thought of was the tag axle and how it and the batteries would cause the issue John S was confronted with.
On my unit, with the old muffler removed, it is wide open with the exception of the condenser with fan. So for the non tag axle units, it should be a much simpler update.
Also,  Xtreme is working on a hinge mod for both sides, radiator and condenser, Looking forward to that lil mod.
Cheers

Re: New Exhaust

Reply #12 –
That does it, too many knowledgeable folks are raving about this mod.  I'm ordering parts. 

Chuck
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: New Exhaust

Reply #13 –
Quote from: Dave M –
One point I had never thought of was the tag axle and how it and the batteries would cause the issue John S was confronted with.

Oof, yeah, if we go that way we have a tag to work around.

Quote from: John S –
It took a full day to find the parts and piece it together.  Then we had to weld on new hangers and gussets too. 

I wonder how similar our required layouts would be ('01 to '03)?  At least both are ISM450. 

-M
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: New Exhaust

Reply #14 –
The resonator mod on my 99 320 was so easy I thought I had done something wrong. jc
JC
1999 U320
 

Re: New Exhaust

Reply #15 –
My issue was the tag and then the batteries were right by the downpipe. That meant the cables were right inline with the pipe so I had to go up and back towards the front then use 2 90's to get it lined up to reuse the tip.  Clean job and if your batteries are on the passenger side, then you should have no real issues with it.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon