Shift or not

Posted By: emarine01

Shift or not - 01/18/13 01:37 AM

Ok as most of you know this is a 200ft mud track question so bear with it and apply what you know to the circumstances, I run lo range with a 727 & a 5k stall that flashes @ 5400 , We shift twice and in 3rd @ the traps we have 85 MPH wheel speed @ 7k, If I run Hi range in first gear @ 7k I have 85 MPH, Which do you think will ET faster? Shift twice in Lo or no shifting in Hi 1st gear?

Posted By: Guitar Jones

Re: Shift or not - 01/18/13 10:31 PM

Quote:

Ok as most of you know this is a 200ft mud track question so bear with it and apply what you know to the circumstances, I run lo range with a 727 & a 5k stall that flashes @ 5400 , We shift twice and in 3rd @ the traps we have 85 MPH wheel speed @ 7k, If I run Hi range in first gear @ 7k I have 85 MPH, Which do you think will ET faster? Shift twice in Lo or no shifting in Hi 1st gear?

Don't know. Lots of variables being a mud truck and all. Why don't you just try it?

Posted By: emarine01

Re: Shift or not - 01/19/13 12:39 AM

Quote:

Quote:

Ok as most of you know this is a 200ft mud track question so bear with it and apply what you know to the circumstances, I run lo range with a 727 & a 5k stall that flashes @ 5400 , We shift twice and in 3rd @ the traps we have 85 MPH wheel speed @ 7k, If I run Hi range in first gear @ 7k I have 85 MPH, Which do you think will ET faster? Shift twice in Lo or no shifting in Hi 1st gear?

Don't know. Lots of variables being a mud truck and all. Why don't you just try it?

Good point Jones ...

.... But then I'll have to wait for spring

Posted By: Cab_Burge

Re: Shift or not - 01/19/13 02:37 AM

Quote:

Quote:

Ok as most of you know this is a 200ft mud track question so bear with it and apply what you know to the circumstances, I run lo range with a 727 & a 5k stall that flashes @ 5400 , We shift twice and in 3rd @ the traps we have 85 MPH wheel speed @ 7k, If I run Hi range in first gear @ 7k I have 85 MPH, Which do you think will ET faster? Shift twice in Lo or no shifting in Hi 1st gear?

Don't know. Lots of variables being a mud truck and all. Why don't you just try it?

Posted By: MMiller

Re: Shift or not - 01/21/13 02:27 AM

Why not just start in 3rd gear, low range? That way the trans is in 1:1 and your gear reduction is clear back in the transfer case.

Wheather I'm 4 wheeling, mud racing, or truck pulling I run low range. It moves the torque further back in the drive line. You will likely not hurt anything with the gas engine, but a buddy used to run a hot cummins with a 727 in an offroad truck. Whenever he used high range, he would either break the output shaft of the trans or the input to the transfer case.

Whenever a Chevy with a 4speed that runs very good tries to pull high range, 1st gear(its slightly faster then low range 2nd), they almost always will brake the coupler between the trans and t-case. If they hook in low range and pull in 2nd, they get to make many passes with no breakage.

Michael

Posted By: Kevins493

Re: Shift or not - 01/21/13 06:57 AM

Quote:

Why not just start in 3rd gear, low range? That way the trans is in 1:1 and your gear reduction is clear back in the transfer case.

Wheather I'm 4 wheeling, mud racing, or truck pulling I run low range. It moves the torque further back in the drive line. You will likely not hurt anything with the gas engine, but a buddy used to run a hot cummins with a 727 in an offroad truck. Whenever he used high range, he would either break the output shaft of the trans or the input to the transfer case.

Whenever a Chevy with a 4speed that runs very good tries to pull high range, 1st gear(its slightly faster then low range 2nd), they almost always will brake the coupler between the trans and t-case. If they hook in low range and pull in 2nd, they get to make many passes with no breakage.

Michael

Also less chance of damaging the sprag than if it was in first.