non speedy vehicle.
without jacking up rear end and spinning tire is there a way to figure R/P gear ratio.
I have final drive ratio on tranny 1:1
height of tire 22 1/4"
what is the missing # i need to figure this out.
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non speedy vehicle.
without jacking up rear end and spinning tire is there a way to figure R/P gear ratio.
I have final drive ratio on tranny 1:1
height of tire 22 1/4"
what is the missing # i need to figure this out.
without jacking up rear end and spinning tire is there a way to figure R/P gear ratio.
I have final drive ratio on tranny 1:1
height of tire 22 1/4"
what is the missing # i need to figure this out.
Without jacking up the rear end . . .
I'm thinking, "NO"
You gotta either rotate the tire one revolution and measure the corresponding rotation of the drive shaft,
or
rotate the drive shaft one revolution and measure the corresponding rotation of the tires.
Then you get out your math book and look up geometry
Then you get a list of the available R/P that were available for that vehicle that year and select the one that is the best fit - you will probably not get your measured result to EXACTLY MATCH the available ratios. Pick the closest match.
I'm thinking, "NO"
You gotta either rotate the tire one revolution and measure the corresponding rotation of the drive shaft,
or
rotate the drive shaft one revolution and measure the corresponding rotation of the tires.
Then you get out your math book and look up geometry
Then you get a list of the available R/P that were available for that vehicle that year and select the one that is the best fit - you will probably not get your measured result to EXACTLY MATCH the available ratios. Pick the closest match.
Yup, there's no "Magic coefficient" that'll work here. (Not even '42' for you hitch-hikers out there) so you'll have to raise up the rear end, put it in 4'th, get out your 30mm box wrench, crank the engine over 1 complete turn, see how far the wheel rotates and get out your calculator and figure it out.
I am surprised that you have a 1-to-1 fourth, but if you say so....
I am surprised that you have a 1-to-1 fourth, but if you say so....
gordon. i said non speedy. it is the tiger with ford toploader and dana 44 rear end.
If your tach is good, why not just drive the thing with a handheld GPS? Get your MPH at 2000 RPM and figure it out.
22.25 inches x 3.1415=69.9 inches per rev. 5.825 feet.
If you get, say, 42.3 MPH at 2000 RPM you figure it this way:
42.3 MPH = .705 miles per minute. You're going that far in 2000 engine revs.
2000 revs times 5.825 feet = 11,650 feet. divided by miles (5280 feet per) that's 2.206 miles.
2.206 miles (2000 tire reves) divides by .705 miles (2000 engine revs)= 3.13, which would be your R&P ratio in this example.
22.25 inches x 3.1415=69.9 inches per rev. 5.825 feet.
If you get, say, 42.3 MPH at 2000 RPM you figure it this way:
42.3 MPH = .705 miles per minute. You're going that far in 2000 engine revs.
2000 revs times 5.825 feet = 11,650 feet. divided by miles (5280 feet per) that's 2.206 miles.
2.206 miles (2000 tire reves) divides by .705 miles (2000 engine revs)= 3.13, which would be your R&P ratio in this example.