So, regarding top speeds again.
#21
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The speed limitr is two bytes in the PROM - one for the fuel cut off ($6C is 108 mph, $7D is 125) and another for the resume (generally 2 mph lower). There is a similar pair that govers the redline (believe 6000 rpm for $5B - 3800 - engines). Those cars that came with "H" rated tires most likely have a 125 mph cutoff. (e.g. 1990 SE).
#22
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Originally Posted by padgett
The speed limitr is two bytes in the PROM - one for the fuel cut off ($6C is 108 mph, $7D is 125) and another for the resume (generally 2 mph lower). There is a similar pair that govers the redline (believe 6000 rpm for $5B - 3800 - engines). Those cars that came with "H" rated tires most likely have a 125 mph cutoff. (e.g. 1990 SE).
I have 3 or 4 totall.. And I'm not even sure if I have the original in the car...lol
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stupid speedo only goes to 85mph, any way i can tell how fast im goin? the only thing i can think of right now is using my dads gps with the ground speed on it and judge by thsat but im not sure how accurate it is
#24
stupid speedo only goes to 85mph, any way i can tell how fast im goin?
Even with that, I used to bury the speedo so I made up a chart that corresponded to engine rpm as read off the tach. 5200 rpm took me to 160 mph with a 2.41 gear ratio. :P
If you have a tachometer then you should use that to give you a pretty close estimate of knowing how fast you are going after 85 mph.
MPH = (.076 x RPM)/Overall gear ratio
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Originally Posted by 2000SilverBullet
MPH = (.076 x RPM)/Overall gear ratio
ill just go as fast as i can and see what the cops have to say
mine would have the 2.84 gear ratio right?
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Originally Posted by GoldenBullet
mine would have the 2.84 gear ratio right?
F17 - ratio, transaxle, final drive 2.84
F79 - ratio, transaxle, final drive 2.97
look for one of these
#29
So with 2.84 in 3rd gear.....
At 4200 rpm, then you could be doing 112 mph.
4500 rpm = 120 mph
But you have 2.97 in 3rd gear so....
4000 rpm = 102 mph
4200 rpm = 107
4500 rpm = 115
4750 rpm = 121
5000 rpm = 128
Of course you could shift into OD 4th gear but you will go slower in 4th than in 3rd with that final ratio, unless you force feed that baby. :P
At 4200 rpm, then you could be doing 112 mph.
4500 rpm = 120 mph
But you have 2.97 in 3rd gear so....
4000 rpm = 102 mph
4200 rpm = 107
4500 rpm = 115
4750 rpm = 121
5000 rpm = 128
Of course you could shift into OD 4th gear but you will go slower in 4th than in 3rd with that final ratio, unless you force feed that baby. :P
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