|
|
06-25-2019, 08:42 AM
|
#1
|
Mini-Skoolie
Join Date: Jun 2018
Location: Iowa
Posts: 28
Year: 1998
Chassis: Bluebird
Engine: Cummins 5.9L inline-6H
|
What gears do I have
Attempting to get from 55mph to 65-70. Not sure what gears i have and what I'd need to replace them with
Attached image of plate on the rear-end. 1998 fs65 bluebird cummins
|
|
|
06-25-2019, 08:55 AM
|
#2
|
Bus Geek
Join Date: May 2014
Location: West Ohio
Posts: 3,678
Year: 1984
Coachwork: Bluebird
Chassis: International 1753
Engine: 6.9 International
Rated Cap: 65
|
5.13:1 according to the plate. Anything can happen though and that plate might not be right. Best is to either count teeth, count rotations, or do the math with your current speed/rpm.
|
|
|
06-25-2019, 09:06 AM
|
#3
|
Bus Nut
Join Date: Dec 2018
Location: Rock Hill, SC
Posts: 255
Year: 1997
Coachwork: International
Chassis: Vista 3600
Engine: DT466E / AT545
Rated Cap: 72
|
Quote:
Originally Posted by Booyah45828
5.13:1 according to the plate. Anything can happen though and that plate might not be right. Best is to either count teeth, count rotations, or do the math with your current speed/rpm.
|
Here's a tool on my website I made to help with the RPM/Speed brute forcing cuz I'm too lazy to count rotations.
SPEED CALCULATOR
I plugged OP's number in with both the common transmissions in that bus (3060 and 2000) and he should be getting much, much faster speeds with 5.13 gearing. I'm guessing the gearing was changed at one point, even with the sixth gear locked OP should be getting much more than 55MPH.
|
|
|
06-25-2019, 10:50 AM
|
#4
|
Bus Geek
Join Date: May 2014
Location: West Ohio
Posts: 3,678
Year: 1984
Coachwork: Bluebird
Chassis: International 1753
Engine: 6.9 International
Rated Cap: 65
|
Quote:
Originally Posted by geminusprime
Here's a tool on my website I made to help with the RPM/Speed brute forcing cuz I'm too lazy to count rotations.
SPEED CALCULATOR
I plugged OP's number in with both the common transmissions in that bus (3060 and 2000) and he should be getting much, much faster speeds with 5.13 gearing. I'm guessing the gearing was changed at one point, even with the sixth gear locked OP should be getting much more than 55MPH.
|
1998 with an ISB could have an at545.
What's your figures say for 1:1 trans with a 5.13 and 40.2 inch tires? I'm betting close to 55 mph at redline.
|
|
|
06-25-2019, 11:01 AM
|
#5
|
Bus Crazy
Join Date: May 2016
Location: Georgia
Posts: 2,264
Year: 2001
Coachwork: Blue Bird
Chassis: IH
Engine: T444E
Rated Cap: 14
|
Quote:
Originally Posted by geminusprime
Here's a tool on my website I made to help with the RPM/Speed brute forcing cuz I'm too lazy to count rotations.
SPEED CALCULATOR
I plugged OP's number in with both the common transmissions in that bus (3060 and 2000) and he should be getting much, much faster speeds with 5.13 gearing. I'm guessing the gearing was changed at one point, even with the sixth gear locked OP should be getting much more than 55MPH.
|
It is unclear if the bus in question has overdrive or not. We need engine RPM's at that speed to know. I see 2 possibilities. Either the bus is running max RPM's at 55 (which mine does) and will need regearing, or it's an overdrive transmission, turning lower RPM's at 55 and is computer limited to 55 (easily unlocked via computer by any shop, can be a DIY thing if you have the computer/link/software to do it).
Since the thread is about gearing, I will assume the former, if for no other reason than to answer the gearing question. Since I have 5.38's in mine, no OD, a 1:1 top gear (manual transmission), 10R22.5 tires, I get around 55 at ~2300 RPM. I'm considering a 4:11 gear (~70 top end) or 3.91 gear (~74 top speed). I'm not too worried about losing acceleration or performance in hills since the trans has a pretty low first gear (I frequently skip it and start in 2nd) - and it's a shorty.
|
|
|
06-25-2019, 12:16 PM
|
#6
|
Mini-Skoolie
Join Date: Jun 2018
Location: Iowa
Posts: 28
Year: 1998
Chassis: Bluebird
Engine: Cummins 5.9L inline-6H
|
Bus sits at 1700 rpm and 55mph
|
|
|
06-25-2019, 12:20 PM
|
#7
|
Mini-Skoolie
Join Date: Jun 2018
Location: Iowa
Posts: 28
Year: 1998
Chassis: Bluebird
Engine: Cummins 5.9L inline-6H
|
Some. Images if they help
|
|
|
06-25-2019, 12:25 PM
|
#8
|
Bus Geek
Join Date: Sep 2014
Location: Eustis FLORIDA
Posts: 23,764
Year: 1999
Coachwork: Thomas
Chassis: Freighliner FS65
Engine: Cat 3126
Rated Cap: 15
|
Quote:
Originally Posted by Hazin
Bus sits at 1700 rpm and 55mph
|
Its electronically limited then.
|
|
|
06-25-2019, 12:55 PM
|
#9
|
Bus Crazy
Join Date: May 2016
Location: Georgia
Posts: 2,264
Year: 2001
Coachwork: Blue Bird
Chassis: IH
Engine: T444E
Rated Cap: 14
|
Quote:
Originally Posted by Hazin
Bus sits at 1700 rpm and 55mph
|
Quote:
Originally Posted by EastCoastCB
Its electronically limited then.
|
Yep. Any truck shop/bus barn should be able to edit that. Mine is hardware limited (2300 at 55), but if mine were a software limit, I'd have it disabled entirely. Many companies and bus shops do that "for safety", and more quantifiably, fuel savings. Also to cut down on speeding tickets.
|
|
|
06-25-2019, 01:34 PM
|
#10
|
Mini-Skoolie
Join Date: Jun 2018
Location: Iowa
Posts: 28
Year: 1998
Chassis: Bluebird
Engine: Cummins 5.9L inline-6H
|
Local cummins service center indicated there is no such thing on my bus, that it is not limited or governed. They recommended sending in the Bosch fuel pump to have it tuned to how i wanted it or to replaced the rear end gears.
I did replace the fuel plate/spring last fall as well as adjusted smoke screw a few times, and it did not change anything.
Quote:
Originally Posted by EastCoastCB
Its electronically limited then.
|
|
|
|
06-25-2019, 04:20 PM
|
#11
|
Bus Geek
Join Date: Sep 2014
Location: Eustis FLORIDA
Posts: 23,764
Year: 1999
Coachwork: Thomas
Chassis: Freighliner FS65
Engine: Cat 3126
Rated Cap: 15
|
Quote:
Originally Posted by Hazin
Local cummins service center indicated there is no such thing on my bus, that it is not limited or governed. They recommended sending in the Bosch fuel pump to have it tuned to how i wanted it or to replaced the rear end gears.
I did replace the fuel plate/spring last fall as well as adjusted smoke screw a few times, and it did not change anything.
|
So its a mechanical bus and you're sure its not governed?
If you're only doing 1700 at 55mph and it won't go any faster a gear swap won't do you any good.
|
|
|
06-25-2019, 04:50 PM
|
#12
|
Bus Geek
Join Date: Sep 2017
Location: Swansboro,NC
Posts: 2,973
Year: 86
Coachwork: Thomas
Chassis: Ford B700
Engine: 8.2
Rated Cap: 60 bodies
|
never said what transmission?
a load of scenarios with the tranny type in hand could answer the question or not.
my all mechanical bus is rated for 175 hp at 3000rpm
not a torque monster like yours is capable of?
mine with an at 545 tranny,6.50 rear ratio and 9r20 tires i get 49mph and maybe a little more on downhill but even 50-52 is it.
we need tranny type before we can help recommend rear gears?
you have already played with the motor settings so before gear recomendations and any motor adjustments we need to know tranny and any tranny being pushed by a motor out of factory design needs a bigger tranny cooler or at least a fan to move air over the tranny cooler.
good luck
|
|
|
06-25-2019, 05:42 PM
|
#13
|
Mini-Skoolie
Join Date: Jun 2018
Location: Iowa
Posts: 28
Year: 1998
Chassis: Bluebird
Engine: Cummins 5.9L inline-6H
|
At545 is plate on trans
There is a print off from the school district it came from dated 6/97 that says
475lb/ft @ 1600rpm 94epa
Cum b 5.9 190hp @ 2300rpm
But I don't have any records of what the district did to it or whoever bought it from them. It changed hands a couple times after its service with me being the first to do more then rip out seats as far as I can tell.
|
|
|
06-25-2019, 05:43 PM
|
#14
|
Mini-Skoolie
Join Date: Jun 2018
Location: Iowa
Posts: 28
Year: 1998
Chassis: Bluebird
Engine: Cummins 5.9L inline-6H
|
Photo of trans plate
|
|
|
06-25-2019, 07:40 PM
|
#15
|
Bus Geek
Join Date: Sep 2014
Location: Eustis FLORIDA
Posts: 23,764
Year: 1999
Coachwork: Thomas
Chassis: Freighliner FS65
Engine: Cat 3126
Rated Cap: 15
|
Quote:
Originally Posted by Hazin
At545 is plate on trans
There is a print off from the school district it came from dated 6/97 that says
475lb/ft @ 1600rpm 94epa
Cum b 5.9 190hp @ 2300rpm
But I don't have any records of what the district did to it or whoever bought it from them. It changed hands a couple times after its service with me being the first to do more then rip out seats as far as I can tell.
|
Maybe your tach is wrong. WIth that setup 55 is about all you'll get. I wouldn't even mess with the fuel or anything till you regear.
Maybe 2700 at 55 instead of 1700?
|
|
|
06-25-2019, 08:18 PM
|
#16
|
Bus Crazy
Join Date: May 2016
Location: Georgia
Posts: 2,264
Year: 2001
Coachwork: Blue Bird
Chassis: IH
Engine: T444E
Rated Cap: 14
|
A quick Google search says '98 was around the time the 24V Cummins 5.9 came out. The OP's builder's plate shows a build date late '97 and shop indicates it's a non-electronic engine. AT545 trans has 1:1 top gear, so yes, it would be tach'ed out at 55.
The redline for a 6BTA5.9 190 HP (475 torque) 12V is 2500 RPM (according to a quick search). All this lines up with the 55 top speed he is getting (though I suspect at 2500 RPM or close to it). So back to the gears, I'd say 4.10 gears will get 65-67, and 3.91 will get 70-73 (Educated guesstimate here, having already mathed mine with similar numbers.)
|
|
|
06-25-2019, 09:43 PM
|
#17
|
Mini-Skoolie
Join Date: Jun 2018
Location: Iowa
Posts: 28
Year: 1998
Chassis: Bluebird
Engine: Cummins 5.9L inline-6H
|
Quote:
Originally Posted by Brad_SwiftFur
A quick Google search says '98 was around the time the 24V Cummins 5.9 came out. The OP's builder's plate shows a build date late '97 and shop indicates it's a non-electronic engine. AT545 trans has 1:1 top gear, so yes, it would be tach'ed out at 55.
The redline for a 6BTA5.9 190 HP (475 torque) 12V is 2500 RPM (according to a quick search). All this lines up with the 55 top speed he is getting (though I suspect at 2500 RPM or close to it). So back to the gears, I'd say 4.10 gears will get 65-67, and 3.91 will get 70-73 (Educated guesstimate here, having already mathed mine with similar numbers.)
|
That's what I was looking for. Thank you. Now to find em and get em in.
|
|
|
07-03-2019, 11:31 PM
|
#18
|
Skoolie
Join Date: Oct 2015
Location: BC Rockies
Posts: 125
Year: 93
Coachwork: Corbiel
Chassis: Ford
Engine: 5.9 Cummins
Rated Cap: 36 pass
|
Quote:
Originally Posted by EastCoastCB
Maybe your tach is wrong. WIth that setup 55 is about all you'll get. I wouldn't even mess with the fuel or anything till you regear.
Maybe 2700 at 55 instead of 1700?
|
I think you and Brad probly have it figured but wouldn't the prudent first move be to verify the tach?
|
|
|
07-03-2019, 11:48 PM
|
#19
|
Traveling
Join Date: Sep 2013
Location: Virginia
Posts: 2,302
Year: None
Coachwork: None
Chassis: None
Engine: None
Rated Cap: None
|
With no electronic limiting and 55 is as fast as you can go at 1700 rpm, are you sure your tranny is using all its forward gears?
|
|
|
07-03-2019, 11:57 PM
|
#20
|
Bus Crazy
Join Date: Dec 2014
Location: Dowdy Lakes, Colorado
Posts: 1,444
Year: 1989
Coachwork: Thomas
Chassis: Saf-T-Liner ER
Engine: 3208 CAT/MT643 tranny
Rated Cap: 87
|
Hazin;
Call that serial number in to Chalk's Bus Parts in Houston. They got me re-geared with an unusual serial gear combination from Eaton. JT is the guy to talk with about this concern. He can come up with some amazing stuff. He got me from a 5.29 to a 4.11 ratio. BIG help! If that's too out-of-the-way, maybe use his help finding the gears working with a local shop? Just tossing out ideas.....
M
__________________
Firearms stand next in importance to the Constitution itself. They are the American people’s liberty teeth and keystone under independence. — George Washington
|
|
|
|
|
Thread Tools |
|
Display Modes |
Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
» Recent Threads |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|