Gear ratio questions
Thread Starter
|
Junior User
Joined: Jan 2003
Posts: 82
Likes: 0
From: Louisiana
Gear ratio questions
I'm trying to figure out what gear ratio I need to run in my upcoming race truck it has a 460, C-6, NP208 (thinking of going to an NP205) 9" rear with a Dana 44 straight axel conversion up front. To use the gear calculators offered by Randy’s ring and Pinion I need to know the gear ratio of the C-6 in final gear and the gear ratio of the NP208 and NP205 in low range. If any of you guys have that info I would sure appreciate it.
Moderator
Joined: Jan 2001
Posts: 56,984
Likes: 2,738
From: Virginia
Gear ratio questions
NP 205
Type: Gear-driven, cast-iron
Low-range ratio: 1.98:1
Weight (lb.): 138
Lubricant: 80- to 90-weight
Length (in.): 13.0 (GM); 16.0 (IH)
Width (in.): 18.0
Height (in.): 12.0
Used by: 1971-1980 Broncos, Blazers, and Ramchargers (and corresponding full-size pickups); the NP 205 is still used on heavy Dodges. Some Dodge and IH models were longer, "divorce-mounted'' versions. The NP 205 has left- or right-side front outputs and a center rear output. Caution is advised: there were many varieties in NP 205 shaft splines and so forth. A PTO plate can be found on the left side of the 'case.
NP 208
Type: Chain-driven, aluminum
Low-range ratio: 2.61:1
Weight (lb): 79
Lubricant: ATF
Length (in): 8.0 (GM); 15.5 (AMC)
Width (in.): 20.0
Height (in.): 5.0
Used by: Many full-size vehicles, including Jeep pickups and Wagoneers (which used a left-side front output shaft). A part-time unit that replaced the stronger, heavier NP 203, the NP 208 can't stand up to the horsepower that the NP 205 can, but failure is more often related to low oil level than too much input torque. The 'case utilized left- or right-side front output shafts. All Jeep model 208s have the same spline and output-shaft size and bolt pattern as the Dana 300.
The c6 is 1 to 1 in high gear
Type: Gear-driven, cast-iron
Low-range ratio: 1.98:1
Weight (lb.): 138
Lubricant: 80- to 90-weight
Length (in.): 13.0 (GM); 16.0 (IH)
Width (in.): 18.0
Height (in.): 12.0
Used by: 1971-1980 Broncos, Blazers, and Ramchargers (and corresponding full-size pickups); the NP 205 is still used on heavy Dodges. Some Dodge and IH models were longer, "divorce-mounted'' versions. The NP 205 has left- or right-side front outputs and a center rear output. Caution is advised: there were many varieties in NP 205 shaft splines and so forth. A PTO plate can be found on the left side of the 'case.
NP 208
Type: Chain-driven, aluminum
Low-range ratio: 2.61:1
Weight (lb): 79
Lubricant: ATF
Length (in): 8.0 (GM); 15.5 (AMC)
Width (in.): 20.0
Height (in.): 5.0
Used by: Many full-size vehicles, including Jeep pickups and Wagoneers (which used a left-side front output shaft). A part-time unit that replaced the stronger, heavier NP 203, the NP 208 can't stand up to the horsepower that the NP 205 can, but failure is more often related to low oil level than too much input torque. The 'case utilized left- or right-side front output shafts. All Jeep model 208s have the same spline and output-shaft size and bolt pattern as the Dana 300.
The c6 is 1 to 1 in high gear
