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mph / rpm ratio?
- Thread starter Baz
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OP
Baz
Yoda
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I think I was doing 60, he said 65, 55 zone etc.
This was campus police.
Tire is 155/80 -13, I think I calculated 6% high with the tire size and took that into consideration, but my speedo is kaput, so I'm using the tach which is fine up to 40mph, after that I calibrate by throwing chicken bones on the passenger seat.
This was campus police.
Tire is 155/80 -13, I think I calculated 6% high with the tire size and took that into consideration, but my speedo is kaput, so I'm using the tach which is fine up to 40mph, after that I calibrate by throwing chicken bones on the passenger seat.
not enuff info but lets play suppose..........
tire diameter = 22"
diff gear ratio= 3.90
........................speed 67 mph
tire diameter = 23"
.......................... 70mph
gear ratio = 4.22
tire = 22"
...........................62 mph
radar gun? ... did you ask for calibration at that time?
estimated speed......mabe able to weasel out
clocked speed.....ask for speedo calibration report.
Short answer.....uphill fight unless you want to spend time seeing Judge Judy then still uphill./ubbthreads/images/graemlins/nopity.gif
tire diameter = 22"
diff gear ratio= 3.90
........................speed 67 mph
tire diameter = 23"
.......................... 70mph
gear ratio = 4.22
tire = 22"
...........................62 mph
radar gun? ... did you ask for calibration at that time?
estimated speed......mabe able to weasel out
clocked speed.....ask for speedo calibration report.
Short answer.....uphill fight unless you want to spend time seeing Judge Judy then still uphill./ubbthreads/images/graemlins/nopity.gif
"""""""""This was campus police."""""
Did the nice policelman used to work at the soup kitchen that Seinfeld used to frequent?
measure the roll out of your tire ...chalk the tread and revolve on the pavement eggzacly one revo and measure the length then math for diameter. Also post that and your diff ratio.
Did the nice policelman used to work at the soup kitchen that Seinfeld used to frequent?
measure the roll out of your tire ...chalk the tread and revolve on the pavement eggzacly one revo and measure the length then math for diameter. Also post that and your diff ratio.
OP
Baz
Yoda
Offline
[ QUOTE ]
tire diameter = 22"
diff gear ratio= 3.90
........................speed 67 mph
Short answer.....uphill fight
[/ QUOTE ]
That's about right, 22", it's fine, if I deserve it then I deserve it, It doesn't go on my record or have to tell insurance, so I'll get it worse from the Mrs when she gets home.
tire diameter = 22"
diff gear ratio= 3.90
........................speed 67 mph
Short answer.....uphill fight
[/ QUOTE ]
That's about right, 22", it's fine, if I deserve it then I deserve it, It doesn't go on my record or have to tell insurance, so I'll get it worse from the Mrs when she gets home.
Re: FIGHT THAT SUCKA!!!
""""""""It doesn't go on my record or have to tell insurance, """""
cummon.....who do you see then...Dean Wrightscool ?? If you go to Oldschool maybe it's a ruler across the knuckles? /ubbthreads/images/graemlins/hammer.gif
I would really ask for calibration......
""""""""It doesn't go on my record or have to tell insurance, """""
cummon.....who do you see then...Dean Wrightscool ?? If you go to Oldschool maybe it's a ruler across the knuckles? /ubbthreads/images/graemlins/hammer.gif
I would really ask for calibration......
OP
Baz
Yoda
Offline
That distance is 69" from chalk to chalk.
I have no reason to suspect I have anything other than a 3.909:1
Woodie, I personally don't think my car is capable of anything faster, from a mechanical pov, however, I'm curious too to see what this math comes out at, it could've been more?
I have no reason to suspect I have anything other than a 3.909:1
Woodie, I personally don't think my car is capable of anything faster, from a mechanical pov, however, I'm curious too to see what this math comes out at, it could've been more?
Woodie
Jedi Warrior
Offline
I've had my Sparky (1970 1275) up to about 75 mph, I m not sure what the rpms were , but they were still below 4000. I have 74000 miles on it. When I ran my spitfire (1980 1500 4 sp) it was almost exactly double rpms to speed, 3000 = just a hair over 60mph. I rememebr that cause the speedo did not work for awhile
Barry, I use a Dream Wheel. It's a dedicated slide rule that has gear vs tire dia vs rpm vs speed and is accurate to about 2%. dont know if there even sold nowadays with palm computers and adders but it do save a lot of time on "what ifs".
Circumfrence to diameter use Pi. and convert to Dia.
Circumfrence to diameter use Pi. and convert to Dia.
jlaird
Great Pumpkin
Offline
https://www.mgcars.org.uk/midgetspriteclub/sprite/sprite_speeds_ratios.htm
Try this for all the data you ever did not need to know.
Try this for all the data you ever did not need to know.
