unick
1/2 ton status
What would the crawl ratio be for a truck with an 87 700R4, ORD doubler, and 4.56 gears be?
lmk
Nick
lmk
Nick
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.
ORD doubler crawl ratio question
- Thread starter unick
- Start date
big83chevy4x4
3/4 ton status
3.06 * 1.96 * 2 * 4.56= 54.698112 /forums/images/graemlins/thumb.gif
3.06 x 3.96 x 4.56 = 55.25
zakk
1/2 ton status
add in the torque converter for 110:1
I'm shooting for 153:1 /forums/images/graemlins/grin.gif
I'm shooting for 153:1 /forums/images/graemlins/grin.gif
[ QUOTE ]
Zakk, how does the torque converter work in to the formula? Are you just multiplying by two? Is it different for different torque convertors? Thanks.
[/ QUOTE ]
The "stall" in the converter allows you to spin the engine without a direct 1:1 coupling to the tranny...the effect is estimated at about a 2:1 ratio (conservative) to maybe 3:1 (optimistic).....
Once you hit the stall speed of the converter, the effect is gone. But for most of the slow speed stuff we do, this extra 2:1 reduction is REAL and welcomed! /forums/images/graemlins/thumb.gif
Zakk, how does the torque converter work in to the formula? Are you just multiplying by two? Is it different for different torque convertors? Thanks.
[/ QUOTE ]
The "stall" in the converter allows you to spin the engine without a direct 1:1 coupling to the tranny...the effect is estimated at about a 2:1 ratio (conservative) to maybe 3:1 (optimistic).....
Once you hit the stall speed of the converter, the effect is gone. But for most of the slow speed stuff we do, this extra 2:1 reduction is REAL and welcomed! /forums/images/graemlins/thumb.gif
sled_dog
1 ton status
so in theory would puting a higher stall converter(not much say 1500) create a more optimal state? Cause you would still have the torque mutliplication?
[ QUOTE ]
so in theory would puting a higher stall converter(not much say 1500) create a more optimal state? Cause you would still have the torque mutliplication?
[/ QUOTE ]
From everything I've read, and seen on this site.....changing the stall speed is more likely to make things worse than better.
Stall is a pretty tough thing to mess with from a "tuning" perspective. It's a PITA to get to the converter, and most of what I've heard indicates that you really need to understand what you're doing or you may just make your setup more unpleasant....
I forget what factory "stall" is, but I thought it was up in the 2000+ RPM range anyway???? /forums/images/graemlins/thinking.gif
so in theory would puting a higher stall converter(not much say 1500) create a more optimal state? Cause you would still have the torque mutliplication?
[/ QUOTE ]
From everything I've read, and seen on this site.....changing the stall speed is more likely to make things worse than better.
Stall is a pretty tough thing to mess with from a "tuning" perspective. It's a PITA to get to the converter, and most of what I've heard indicates that you really need to understand what you're doing or you may just make your setup more unpleasant....
I forget what factory "stall" is, but I thought it was up in the 2000+ RPM range anyway???? /forums/images/graemlins/thinking.gif
[ QUOTE ]
3.06 x 3.96 x 4.56 = 55.25
[/ QUOTE ]
Close, but it's x2 not +2, big83 got it right. The farther away from 2:1 get the more wrong you will be. Klune-V "Goliath" & an NP241 (2.7:1 & 2.72:1) 102.48:1 vs 75.63:1 or Klune-V "David" & an Atlas (4:1 & 4.3:1) 240:1 vs 115.81:1.
3.06 x 3.96 x 4.56 = 55.25
[/ QUOTE ]
Close, but it's x2 not +2, big83 got it right. The farther away from 2:1 get the more wrong you will be. Klune-V "Goliath" & an NP241 (2.7:1 & 2.72:1) 102.48:1 vs 75.63:1 or Klune-V "David" & an Atlas (4:1 & 4.3:1) 240:1 vs 115.81:1.
Trans 1st x range box x x-fer case low x R&P
700R4 x NP203 range box x NP205 x his R&P ratio
3.06:1 x 2:1 x 1.96:1 x 4.56
In the example #s I used his 700R4 and R&P ratio to get the finial drive ratios listed.
700R4 x NP203 range box x NP205 x his R&P ratio
3.06:1 x 2:1 x 1.96:1 x 4.56
In the example #s I used his 700R4 and R&P ratio to get the finial drive ratios listed.
[ QUOTE ]
[ QUOTE ]
Zakk, how does the torque converter work in to the formula? Are you just multiplying by two? Is it different for different torque convertors? Thanks.
[/ QUOTE ]
The "stall" in the converter allows you to spin the engine without a direct 1:1 coupling to the tranny...the effect is estimated at about a 2:1 ratio (conservative) to maybe 3:1 (optimistic).....
Once you hit the stall speed of the converter, the effect is gone. But for most of the slow speed stuff we do, this extra 2:1 reduction is REAL and welcomed! /forums/images/graemlins/thumb.gif
[/ QUOTE ]
Somewhere in my Granddad's FSM or literature on his GMC motohome it states that the torque multiplication factor of the stock converter is 2.6:1 and cautions that only X p/n converter be used in the GMC coaches as the typical TH400 converter's factor is ~2.0-2.3:1 depending on application. Unfortunately he's already checked, that converter no longer exists in any inventory anywhere in the states.
[ QUOTE ]
Zakk, how does the torque converter work in to the formula? Are you just multiplying by two? Is it different for different torque convertors? Thanks.
[/ QUOTE ]
The "stall" in the converter allows you to spin the engine without a direct 1:1 coupling to the tranny...the effect is estimated at about a 2:1 ratio (conservative) to maybe 3:1 (optimistic).....
Once you hit the stall speed of the converter, the effect is gone. But for most of the slow speed stuff we do, this extra 2:1 reduction is REAL and welcomed! /forums/images/graemlins/thumb.gif
[/ QUOTE ]
Somewhere in my Granddad's FSM or literature on his GMC motohome it states that the torque multiplication factor of the stock converter is 2.6:1 and cautions that only X p/n converter be used in the GMC coaches as the typical TH400 converter's factor is ~2.0-2.3:1 depending on application. Unfortunately he's already checked, that converter no longer exists in any inventory anywhere in the states.
this is what i am shooting for:
3.06 x 3:1 (wms) x 1.96 x 5.13 = 92.3 /forums/images/graemlins/eek.gif
3.06 x 3:1 (wms) x 1.96 x 5.13 = 92.3 /forums/images/graemlins/eek.gif
SF87K5
1/2 ton status
I like this set up.
3.06 x 2.72 x 5.13 x 2.7 =115.28 /forums/images/graemlins/thumb.gif
Of course thats also with a $1700 Klune-V Goliath underdrive also. For those also woundering about the David's 4.1 underdrive. It is highky recommanded them not be used on full size trucks. Klune-V info page. /forums/images/graemlins/thumb.gif
3.06 x 2.72 x 5.13 x 2.7 =115.28 /forums/images/graemlins/thumb.gif
Of course thats also with a $1700 Klune-V Goliath underdrive also. For those also woundering about the David's 4.1 underdrive. It is highky recommanded them not be used on full size trucks. Klune-V info page. /forums/images/graemlins/thumb.gif
