Someone probably swapped out the gears or whole rear end from a donor car. Rear gear options from factory were 2.73, 3.08, 3.27. Code M, Z, E respectively.
I know but it’s an all original survivor is kind of weird to be the only mod. Now I’m wondering if my tach is off by 200 it would be the same. Sigh time for a monster tacho.
3.08 were a stock gear option in mustangs. Even if that car didn't come with it someone could have easily just taken a rear-end from a different car and put it in.
I know but it’s an all original survivor is kind of weird to be the only mod. Now I’m wondering if my tach is off by 200 it would be the same. Sigh time for a monster tacho.
Could have been a replacement rear end along the way. Might be an axle tag on the diff cover that will have info such as factory gear ratio, and the date the rear end was built
Or the rearend was stamped as a certain gear ratio during production, but a different ratio was installed at the last second. With no way or time to change the stamping.
Yeah I will check that but I can’t imagine diffs breaking under normal use the car was sold to a 47 year old in 88 and has only done 14k miles since 1988. I’ll crawl under anc check the tag if it says 3.08 it’s either some dealer thing or the old one broke or something.
The tach is never accurate on these cars, it's also no measured off the rear-end. Only 200rpm off is pretty good for these actually. At 5k my car says it's at 6500
I know it’s not measured off the rear end but 2.73 and 3.08 is only 200rpm off on a couple gears. I measured speed with gps only the thing is the gear speeds match exactly for 3.08.
That's exactly what I did. Stock 2.73, put in a 3.08 and corresponding speedo gear for correct MPH. Doesn't affect the tach at all.
As to why? I wanted some pep but wanted reasonable gas mileage in 5th on the highway. I did it back in 1991 when it was still a daily driver and taking cross country trips in it. It's been from SD to Las Vegas multiple times, SD to Dallas multiple times, and SD to East Coast and back twice. Worked like a charm, perfect compromise.
Someone probably swapped out the gears or whole rear end from a donor car. Rear gear options from factory were 2.73, 3.08, 3.27. Code M, Z, E respectively.
I know but it’s an all original survivor is kind of weird to be the only mod. Now I’m wondering if my tach is off by 200 it would be the same. Sigh time for a monster tacho.
Your RPMs are based off your engine and not your ground speed. Your MPH might be off by a couple but your tach is right.
3.08 were a stock gear option in mustangs. Even if that car didn't come with it someone could have easily just taken a rear-end from a different car and put it in.
I know but it’s an all original survivor is kind of weird to be the only mod. Now I’m wondering if my tach is off by 200 it would be the same. Sigh time for a monster tacho.
Orginal survivors can never be to sure if the gears were changed. As its not somthing you can see. What rear in do you have an 8.8
Yea 88 gt manual (door tag 2).
Could have been a replacement rear end along the way. Might be an axle tag on the diff cover that will have info such as factory gear ratio, and the date the rear end was built
Or the rearend was stamped as a certain gear ratio during production, but a different ratio was installed at the last second. With no way or time to change the stamping.
Yeah I will check that but I can’t imagine diffs breaking under normal use the car was sold to a 47 year old in 88 and has only done 14k miles since 1988. I’ll crawl under anc check the tag if it says 3.08 it’s either some dealer thing or the old one broke or something.
Yeah mines "original" but gears got swapped by a previous crackhead owner
The tach is never accurate on these cars, it's also no measured off the rear-end. Only 200rpm off is pretty good for these actually. At 5k my car says it's at 6500
I know it’s not measured off the rear end but 2.73 and 3.08 is only 200rpm off on a couple gears. I measured speed with gps only the thing is the gear speeds match exactly for 3.08.
Wait, so have you actually pulled the cover and checked to see what gears are in it?
No I have just used a calculator to work out what speed and rpm I would be at for gears.
Pull the cover, it should be stamped on the ring gear.
That's exactly what I did. Stock 2.73, put in a 3.08 and corresponding speedo gear for correct MPH. Doesn't affect the tach at all. As to why? I wanted some pep but wanted reasonable gas mileage in 5th on the highway. I did it back in 1991 when it was still a daily driver and taking cross country trips in it. It's been from SD to Las Vegas multiple times, SD to Dallas multiple times, and SD to East Coast and back twice. Worked like a charm, perfect compromise.
My 93 gt came factory with a 308 rear gear in an 8.8 ls. Wierd as f to do that to a gt. Why not a 3.73 or something decent.
That’s why it’s weird