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Old 10-19-2016, 10:11 AM   #11
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gear bound is if you are consistently running at the RPM redline and not going fast enough... power bound is if you are floored and running belkow your RPM redline.. or when your bus slows on hills the RPM's are dropping also...

if you are gear bound.. in a 2003 you should have a 6 speed transmission that is limited to 5 speeds by computer.. if you are gear bound and got your 6th gear unlocked, that would help significantly with that..

if you are power-bound then doing some upgrades would help.. but first you have to determine whether gear or power bound..

-Christopher
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Old 10-19-2016, 10:29 AM   #12
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And remember...horsepower is not what moves a load. It is torque. But even with tons of torque, without the right gearing you'll never hit the right speeds at the right RPM's to keep everything happy.
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Old 10-19-2016, 10:36 AM   #13
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Tango is right!!

the T-444E in most scenerios is designed to run ast a max of 2700 RPM.. HOWEVER it PEAKS at 2300 RPM.. so as close to 2300 RPM as it can be kept is where you are going to get the most power from it..

running it any faster is simply a gift to be able to over-run on flat ground due to gears if necessary...

some of the tunes out there change where the TQ / HP curve crosses and alters the RPMs...

Ford spins these guys well over 3000 so the bottom end can take it.. However im guessing a consumer pickup truck may not have have a 300,000 mile design to it before rebuild like a commercial truck...

I may be wrong but i think I read somewhere that 250k is the average life of a T-444E before expecting to do major things to it.. doesnt mean yoiu wont go farther and doesnt mean you wont need to repair it sooner.. its an average..

-Christopher
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Old 10-19-2016, 10:57 AM   #14
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Thanks for the replies, very good and useful information.

I have to check for my notes, but I believe my rear end is a 7:17 and was told that at 175HP @ 2600 Max RPM's, and that would equate to 67 MPH wide open.

I just picked up my bus a couple of weeks ago and drove it 260 miles home after having the school district re-program the governor to 75 mph. I could never get it over 70 even descending down hills.

I'll have to check on the sixth gear reference.
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Old 10-19-2016, 12:02 PM   #15
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tryi ng to get it over 70 without additional gearing could have bad effects... if in fact you were at 2600 running 67 MPH.. with the TCC locked in.. and downhill you attempt to run it over 70.. im assuming the TCC stays locked which means now your revs are going over the stated 2700 RPM factory max.. the computer may be smart enough to unlock the TCC so the engine just free revs at 2600... I dont know enough about the later model allisons to know howe it handles over-speed on a downhill..

at the very least you were putting zero input power to the bus at that poiont so your downhill speed was a Big ole Box against the wind and helped by gravity.. has to be one heck of a hill to coast over 70 in a bus...

-Christopher
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Old 10-19-2016, 01:28 PM   #16
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This was just something that I never really thought about before this, so I wasn't sure if it was a mechanical problem or not. After the discussions it makes all the sense on the world. I did learn from International that different states require different gearing on their buses, so it is possible that depending on the originating state of your bus, you could end up with a better gear ratio. NC for instance is 6:83 on the standard bus and 6:50 on the activity buses at 215 HP, to get little Johnny to his game faster.
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Old 10-19-2016, 01:32 PM   #17
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I am not trying to overcome my gearing. My engine is computer controlled and as I coast down hill, watching the RPM's, it stops giving me power at 55. I should be gaining momentum downhill, not cutting out. This is all I'm trying to fix.
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Old 10-19-2016, 01:43 PM   #18
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I had to remove the speed limiter of 55 on my latest Bus to go over 55.. if your RPMs are dropping off and going down below redline when you hit 55.. then you have a Computerized speed limiter... thats easy to get rid of..


once i did that then i could run it up to its RPM limiter, which I wont change.. I have a self imposed RPM limit of 2600 and the factory design is 2700.. (supposedly theres a way to hack the computer and alter the factory limit.. but im not goiung to do it on a 145,000 mile motor...

-Christopher
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Old 10-19-2016, 01:45 PM   #19
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Quote:
Originally Posted by cadillackid View Post
I had to remove the speed limiter of 55 on my latest Bus to go over 55.. if your RPMs are dropping off and going down below redline when you hit 55.. then you have a Computerized speed limiter... thats easy to get rid of..


once i did that then i could run it up to its RPM limiter, which I wont change.. I have a self imposed RPM limit of 2600 and the factory design is 2700.. (supposedly theres a way to hack the computer and alter the factory limit.. but im not goiung to do it on a 145,000 mile motor...

-Christopher
Chris,


Short of taking it to an International dealer, can I do this myself with the right software?
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Old 10-19-2016, 04:02 PM   #20
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the software to do it is servicemaxx J1708 and international gives it away free... HOWEVER the hardware device isnt cheap... I bought the NEXIQ USB LINK 2 device.. there may be another device which is compatible with servicemaxx.. someone mentioned a TVIT device, however I couldnt find where to buy one..

we need a skoolie meetup where i can bring my device and everyone with the T444E or DT-466E could reprogram their computers...

my Bus goes into the paint shop here soon, at that point i wont need the device for awhile.. Need to find a way to safely ship it around.. it seems pretty durable..

-Christopher
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