Running a Split gear ratio - Competition Diesel.Com

98dodgecummins · 02-07-2021, 08:52 AM

Hi everyone ive got a 2.6 smoothbore pull truck, right now i'm running 4.88 gears front and rear, seems like the truck needs a little more wheel speed. would I be better off changing front and rear to 4.56s or would it be better to keep rear 4.88 and front to 4.56s. truck makes 800 hp on engine dyno just dont want to go to high of a gear and not have enough power. running 35 inch tires on a hard track I usually snuff out at the end. running nv4500 in 4lo 4th gear.I dont know a whole lot about split gearing any help would be appreciated thanks.

98dodgecummins · 02-07-2021, 09:35 AM

SMTTPA 2.6 Work Stock Diesel Trucks from Licking MO 2020! - YouTube

MMTTPA 2.6 Diesel Trucks from California MO Moniteau County Fair 2020! - YouTube

First video is a loose track and 2nd is a tight track im the white and black 2nd gen.

zstroken · 02-07-2021, 12:21 PM

I have run 4.56 fronts with a 35" tire, and 4.63 with a 33" rear.

TheHammer · 02-07-2021, 03:07 PM

Quote:

Originally Posted by 98dodgecummins

Hi everyone ive got a 2.6 smoothbore pull truck, right now i'm running 4.88 gears front and rear, seems like the truck needs a little more wheel speed. would I be better off changing front and rear to 4.56s or would it be better to keep rear 4.88 and front to 4.56s. truck makes 800 hp on engine dyno just dont want to go to high of a gear and not have enough power. running 35 inch tires on a hard track I usually snuff out at the end. running nv4500 in 4lo 4th gear.I dont know a whole lot about split gearing any help would be appreciated thanks.

Back in the slotted cover days, most trucks around here ran a profab nv. Solves what you are describing

98dodgecummins · 02-07-2021, 03:39 PM

So would a profab nv give me a little more wheel speed i wonder what the final drive would be with one right now im at 13.2 final drive. how much would one of those run. thanks

zstroken · 02-07-2021, 03:58 PM

Quote:

Originally Posted by 98dodgecummins

So would a profab nv give me a little more wheel speed i wonder what the final drive would be with one right now im at 13.2 final drive. how much would one of those run. thanks

http://nebula.wsimg.com/c3a07b06ce42...&alloworigin=1

IOWA · 02-08-2021, 07:53 AM

Just here to see the discussion!

bigstacks95 · 02-08-2021, 11:45 AM

I have run split ratios for years. 5.29 in the rear and 4.88 up front. It worked great with the drop box where you can speed up or slow down the wheels there so you can keep it in your optimum range. It almost kinda feels like when you run a faster gear in the front in "stretches" the truck. Think about how much more traction the rear end has over the front when the sled weight gets on it. I thought that the front would be working harder therefore keeping it pulling later in the run. That being said I have a stack of Dana 60 parts in the scrap pile that didn't agree with me but hey, we don't sled pull to be easy on parts. Thank god for open driveline now

*Smokem* · 02-08-2021, 12:00 PM

That is a tough group of 2.6 trucks in Missouri, an honest answer would most likely be to find more power and not worry about the gearing.

ryanss22 · 02-08-2021, 02:16 PM

I run 4.88 out back and 4.56 up front. I can unlock the hubs for the pits. Works good

pullingramrod · 02-09-2021, 06:32 PM

If you’re snuffing with your 4.88’s then gearing the truck faster may not be the answer. Easier said than done (2.6 smooth bore) but try to find more power then maybe a 4.63/4.56 combo would work especially with single rears.

YoungDiesel27 · 02-09-2021, 07:02 PM

Find more power. The profab NV4500 are useful for different tracks.

98dodgecummins · 02-09-2021, 07:23 PM

Thanks guys yeah I'm pretty new too pulling just trying to get all the info I can get that's my plan would like to be closer to 1000 hp looks like where I got my engine dynoed he said my injectors were holding me back might look into something different running 6x0.018 single feed injectors . I'll probably stick with 4.88s for now

Sarafin · 02-12-2021, 04:09 PM

Quote:

Originally Posted by 98dodgecummins

Thanks guys yeah I'm pretty new too pulling just trying to get all the info I can get that's my plan would like to be closer to 1000 hp looks like where I got my engine dynoed he said my injectors were holding me back might look into something different running 6x0.018 single feed injectors . I'll probably stick with 4.88s for now

Yeah you could definitely use some more injector, Id say at the very least dual feeds if not bigger on the nozzle. someone like Smokem could be more help finding the right tip for your application , quite a few puller running his stuff

ryanss22 · 02-21-2021, 06:13 AM

2nd smokem on here. He runs infinite performance! A great stand-up guy and willing to help out when he can.

02-07-2021, 08:52 AM	#1
98dodgecummins Name: 98dodgecummins Title: Rookie Status: Not Here Join Date: Dec 2009 Member`s Gallery Posts: 16	Running a Split gear ratio Hi everyone ive got a 2.6 smoothbore pull truck, right now i'm running 4.88 gears front and rear, seems like the truck needs a little more wheel speed. would I be better off changing front and rear to 4.56s or would it be better to keep rear 4.88 and front to 4.56s. truck makes 800 hp on engine dyno just dont want to go to high of a gear and not have enough power. running 35 inch tires on a hard track I usually snuff out at the end. running nv4500 in 4lo 4th gear.I dont know a whole lot about split gearing any help would be appreciated thanks.

02-07-2021, 12:21 PM	#3
zstroken Name: zstroken Title: For $$$ your name here Status: Not Here Join Date: Sep 2006 Location: Western Michigan(by the lake) Member`s Gallery Posts: 23,151	I have run 4.56 fronts with a 35" tire, and 4.63 with a 33" rear. __________________ 2008 4x4 Megacab, 68RFE 97 Dodge gone.... 24V P-Pump Mafia member #1(retired) Thanks to Mumau Diesel, Goerend Transmission, Northeast Diesel Service!

02-08-2021, 07:53 AM	#7
IOWA Name: IOWA Title: Never enough. Status: Not Here Join Date: Mar 2013 Location: Mid Michigan Member`s Gallery Posts: 51	Just here to see the discussion! __________________ '14 Dodge Cummins Mega Dually - 6.7 / 68RFE - Tow Pig '99 Dodge Cummins - ECSB - 12v NV4500 - 2.6SB Puller '11 Duramax CCSB - Built Trans/Compounds/10mm '06 Duramax RCSB - Parts Runner

02-08-2021, 11:45 AM	#8
bigstacks95 Name: bigstacks95 Title: Diesel Doc Status: Not Here Join Date: Jul 2008 Location: Falls Village, CT Member`s Gallery Posts: 2,030	I have run split ratios for years. 5.29 in the rear and 4.88 up front. It worked great with the drop box where you can speed up or slow down the wheels there so you can keep it in your optimum range. It almost kinda feels like when you run a faster gear in the front in "stretches" the truck. Think about how much more traction the rear end has over the front when the sled weight gets on it. I thought that the front would be working harder therefore keeping it pulling later in the run. That being said I have a stack of Dana 60 parts in the scrap pile that didn't agree with me but hey, we don't sled pull to be easy on parts. Thank god for open driveline now __________________ --Dave-- 58 Dodge Power Wagon 3.0 Limited Pro Stock diesel pulling truck 2020 Ram 3500 HO/Aisin Laramie/night tow rig

02-08-2021, 12:00 PM	#9
Smokem Name: Smokem Title: Turbler Status: Not Here Join Date: May 2006 Location: Iowa Member`s Gallery Posts: 5,565	That is a tough group of 2.6 trucks in Missouri, an honest answer would most likely be to find more power and not worry about the gearing. __________________ Infinite Performance

02-07-2021, 09:35 AM	#2
98dodgecummins Name: 98dodgecummins Title: Rookie Status: Not Here Join Date: Dec 2009 Member`s Gallery Posts: 16	SMTTPA 2.6 Work Stock Diesel Trucks from Licking MO 2020! - YouTube MMTTPA 2.6 Diesel Trucks from California MO Moniteau County Fair 2020! - YouTube First video is a loose track and 2nd is a tight track im the white and black 2nd gen.

02-07-2021, 03:39 PM	#5
98dodgecummins Name: 98dodgecummins Title: Rookie Status: Not Here Join Date: Dec 2009 Member`s Gallery Posts: 16	So would a profab nv give me a little more wheel speed i wonder what the final drive would be with one right now im at 13.2 final drive. how much would one of those run. thanks

02-08-2021, 02:16 PM	#10
ryanss22 Name: ryanss22 Title: Too Much Time Status: Not Here Join Date: Jul 2012 Location: small town central ny Member`s Gallery Posts: 736	I run 4.88 out back and 4.56 up front. I can unlock the hubs for the pits. Works good __________________ 96 fummins 12V puller, few other goodies BUILT NOT BOUGHT!!!!to

02-09-2021, 06:32 PM	#11
pullingramrod Name: pullingramrod Title: Rookie Status: Not Here Join Date: Jan 2010 Location: Cynthiana KY Member`s Gallery Posts: 3	If you’re snuffing with your 4.88’s then gearing the truck faster may not be the answer. Easier said than done (2.6 smooth bore) but try to find more power then maybe a 4.63/4.56 combo would work especially with single rears.

02-09-2021, 07:02 PM	#12
YoungDiesel27 Name: YoungDiesel27 Title: Never Enough Time Status: Not Here Join Date: Jul 2010 Location: West Virginia Member`s Gallery Posts: 825	Find more power. The profab NV4500 are useful for different tracks. __________________ EFI Live, HP Tuners, Smarty custom tuning

02-09-2021, 07:23 PM	#13
98dodgecummins Name: 98dodgecummins Title: Rookie Status: Not Here Join Date: Dec 2009 Member`s Gallery Posts: 16	Thanks guys yeah I'm pretty new too pulling just trying to get all the info I can get that's my plan would like to be closer to 1000 hp looks like where I got my engine dynoed he said my injectors were holding me back might look into something different running 6x0.018 single feed injectors . I'll probably stick with 4.88s for now

02-21-2021, 06:13 AM	#15
ryanss22 Name: ryanss22 Title: Too Much Time Status: Not Here Join Date: Jul 2012 Location: small town central ny Member`s Gallery Posts: 736	2nd smokem on here. He runs infinite performance! A great stand-up guy and willing to help out when he can. __________________ 96 fummins 12V puller, few other goodies BUILT NOT BOUGHT!!!!to