Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
RV Trip Planning Discussions

Go Back   iRV2 Forums > MOTORHOME FORUMS > Class A Motorhome Discussions
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 02-26-2014, 08:59 AM   #1
Junior Member
 
Join Date: Jan 2014
Posts: 4
ISB 300 tweaking

I have a ISB 300 in my 03 Coachmen 38 class A. I'm not impressed with the stock 3.5" pretzel exhaust and air intake. As an old time trucker who owned a 03 Dodge with a hot 5.9 cummins I appreciate the benefits of big exhaust and lots of fresh air on the intake side.

Has anyone here tweaked their ISB 300 cummins with larger exhaust, air intake modifications and maybe CPU tweaks? I'm looking for a little more power and fuel mileage without breaking the bank. Love to get some feedback on this.
Paulknibbs is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 02-26-2014, 05:59 PM   #2
Senior Member
 
ladagobago's Avatar
 
Winnebago Owners Club
Freightliner Owners Club
Join Date: Dec 2010
Location: DW Driver - Englewood FL
Posts: 1,448
Blog Entries: 11
should move to the cummins section

Quote:
Originally Posted by Paulknibbs View Post
I have a ISB 300 in my 03 Coachmen 38 class A. I'm not impressed with the stock 3.5" pretzel exhaust and air intake. As an old time trucker who owned a 03 Dodge with a hot 5.9 cummins I appreciate the benefits of big exhaust and lots of fresh air on the intake side.

Has anyone here tweaked their ISB 300 cummins with larger exhaust, air intake modifications and maybe CPU tweaks? I'm looking for a little more power and fuel mileage without breaking the bank. Love to get some feedback on this.

sure they have and there is much to read under Cummins
__________________
La Dagobago
99 36 FL Winne Chieftain 5.9 ISB Turbo Cummins DP, 24' box with HD Sporty Hobby of 1970's Suzuki dirt bike restoration. Visit my blog.
ladagobago is offline   Reply With Quote
Old 02-26-2014, 07:03 PM   #3
Senior Member
 
Join Date: Jun 2007
Posts: 246
I have a "B" and not an ISB, however, I had a 2 ft 3" piece of pipe(heat shrunk to 2.870" OD) going from the turbo to the 4" Pacbrake that I thought was restricting exhaust. I built a 4" pipe to replace it and also installed a magnaflow 4" muffler and some 4" pipe to complete the exhaust. My seat dyno sure felt better climbing the steep grades out here in the west and the exhaust temps dropped nearly 100 degrees.
sjholt is offline   Reply With Quote
Old 02-26-2014, 08:03 PM   #4
"Formerly Diplomat Don"
 
Dutch Star Don's Avatar
 
Newmar Owners Club
Join Date: Apr 2005
Location: Moorpark, Ca.
Posts: 23,914
Mods like you're talking about are always good, except the CPU mod. Make sure you don't exceed the transmission limits. Some of the older coaches came with the 2500 Allison and it's limited on what torque it will handle.
__________________
Don & Mary
2019 Newmar Dutch Star 4018 (Freightliner)
2019 Ford Raptor
Dutch Star Don is offline   Reply With Quote
Old 02-27-2014, 07:46 AM   #5
Junior Member
 
Join Date: Jan 2014
Posts: 4
Sorry La Dagobago...new to the site...having a hard time negotiating to the right place. Too bad you didn't put in a link to where I can find "Cummins"
Paulknibbs is offline   Reply With Quote
Old 02-27-2014, 09:51 AM   #6
Senior Member
 
Join Date: Nov 2013
Location: Florida
Posts: 294
Quote:
Originally Posted by Paulknibbs View Post
Sorry La Dagobago...new to the site...having a hard time negotiating to the right place. Too bad you didn't put in a link to where I can find "Cummins"
Go to the main forum list and scroll down......

I get that his remark wasn't the nicest but it doesn't really need a link spoon fed to you.
__________________
1998 Bounder 36s V10 F53
ohhwell is offline   Reply With Quote
Old 02-27-2014, 04:08 PM   #7
Senior Member
 
ladagobago's Avatar
 
Winnebago Owners Club
Freightliner Owners Club
Join Date: Dec 2010
Location: DW Driver - Englewood FL
Posts: 1,448
Blog Entries: 11
See cummins under forums

Quote:
Originally Posted by Paulknibbs View Post
Sorry La Dagobago...new to the site...having a hard time negotiating to the right place. Too bad you didn't put in a link to where I can find "Cummins"
When clicking RV forums then see "power train garage and find Cummins etc.
I wasn't trying to be unkind but only that there is a lot written on his ideas.

When you are on the forum you can do a search within the forum for items of interest.
Good luck
__________________
La Dagobago
99 36 FL Winne Chieftain 5.9 ISB Turbo Cummins DP, 24' box with HD Sporty Hobby of 1970's Suzuki dirt bike restoration. Visit my blog.
ladagobago is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Cummins ISB 350 hp overheat Dmintzer Cummins Engines 41 12-16-2014 10:31 AM
ISB (D) vs ISL (MA) James Macfet Newmar Owner's Forum 16 09-24-2013 11:30 PM
275 isb manual? elang Cummins Engines 1 09-21-2013 09:53 AM

» Featured Campgrounds

Reviews provided by


All times are GMT -6. The time now is 10:50 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.