What will RPMs be with 373 gears in auto

[FastDriver]

Actually, that's false. Gears absolutely do affect REAR WHEEL torque. You won't (*shouldn't) see a change in the number on the dyno, because it calculates/reports the torque of the engine as measured at the wheels and adjusted for the gears (trans & differential) & tire size through mathematical calculations that derive the total gear ratio by comparing the RPM of the drum to the RPM of the engine (effectively). But the physics of what's happening at the tire is absolutely, unquestionably affected by the gear or the tire size. You are precisely right to compare the 'feel' of acceleration to the torque produces at the wheel.

I have 225/60/16 on stock pony rims - when tire change is needed , if I drop down in height a bit to a 55 or 50 it should give more off line torque ? It will harden the ride a bit with less air though and may look too short on tires - maybe a half inch drop in height would be nice compromise before I do gears ( 373 sound reasonable for daily driver with highway option )

If you drop from your 225/60/16 to a 225/55/16, and keep in mind that the sidewall is affected by both the tread width number (1st) and the sidewall series number (2nd), that would effectively act like you just went from 3.27 to a 3.38. However, 225/55/16 is actually the stock size for the later foxes. So, it's more accurate to say you're returning to 3.27 from a 3.16.

Likewise, if you drop from your 225/60/16 to a 225/50/16, and keep in mind that the sidewall is affected by both the tread width number (1st) and the sidewall series number (2nd), that would effectively act like you just went from 3.27 to a 3.51. However, again since 225/55/16 is actually the stock size for the later foxes it's more accurate to say you're going from 3.27s to a 3.39.

*Actual tire diameters vary by manufacturer and I simply used the direct mathematical calculations of the tire specifications, but it should be pretty close.

Taller sidewalls have other uses like shock absorption & they store some of the shock of the launch, too. So, bear that in mind if you treat the tires like gears, you may be giving up traction, though that's unlikely to be a big deal at stockish power levels, and you may be pounding your suspension and your back a bit harder when you hit those bumps.

 

[CarMichael Angelo]

Actually, that's false. Gears absolutely do affect REAR WHEEL torque. You won't (*shouldn't) see a change in the number on the dyno, because it calculates/reports the torque of the engine as measured at the wheels and adjusted for the gears (trans & differential) & tire size through mathematical calculations that derive the total gear ratio by comparing the RPM of the drum to the RPM of the engine (effectively). But the physics of what's happening at the tire is absolutely, unquestionably affected by the gear or the tire size. You are precisely right to compare the 'feel' of acceleration to the torque produces at the wheel.



If you drop from your 225/60/16 to a 225/55/16, and keep in mind that the sidewall is affected by both the tread width number (1st) and the sidewall series number (2nd), that would effectively act like you just went from 3.27 to a 3.38. However, 225/55/16 is actually the stock size for the later foxes. So, it's more accurate to say you're returning to 3.27 from a 3.16.

Likewise, if you drop from your 225/60/16 to a 225/50/16, and keep in mind that the sidewall is affected by both the tread width number (1st) and the sidewall series number (2nd), that would effectively act like you just went from 3.27 to a 3.51. However, again since 225/55/16 is actually the stock size for the later foxes it's more accurate to say you're going from 3.27s to a 3.39.

*Actual tire diameters vary by manufacturer and I simply used the direct mathematical calculations of the tire specifications, but it should be pretty close.

Taller sidewalls have other uses like shock absorption & they store some of the shock of the launch, too. So, bear that in mind if you treat the tires like gears, you may be giving up traction, though that's unlikely to be a big deal at stockish power levels, and you may be pounding your suspension and your back a bit harder when you hit those bumps.

I stand corrected.

 

[FastDriver]

No worries. You also might have been thinking of power. When you get to the straight line, power = force * distance.

With gears, however much you increase the force, you also shorten the distance. So, gears do not increase power.

 

[General karthief]

Years ago we tried the 'smaller tire lower gear' thing at the drag strip thinking we could get a better start off the line but the car was slower because all we did was spin off the line.
we were young and just having fun.

 

[MrPerfect2]

Found some parts - on my Stock 91 do I have 28 or 31spline ? Does this seem like a good price ? Does it look to be in good shape ? $100

 

[Olivethefet]

Should be 28 spline. My 92 has 28s. $100 seems fair. As for how they look.... I'll let someone that actually knows what to look for chime in on that.

 

[LILCBRA]

Real world testing in high school! lol With a shorter tire you will be quicker off the line but have a slower top speed. My buddy had a 78 II Ghia and I had a 77 II coupe, otherwise both were identical. He had a set of 205/60-13s iirc, I had the stock size 195/70-13. He would take me from the dig every time. Being young and dumb we also had them on the highway at one point. My top speed was around 120 and I was pulling away from him. Being older and questionably wiser now, realizing that his tire was shorter meant he had a smaller circumference so for every revolution that my tire would make, he would make like 1.1 or whatever. That essentially gave him a lower rear gear without having to change gears.

As for your pics, it doesn't look horrible to me but I question the wear on the pinion gear. It's a little hard to see the wear pattern on the ring gear, but it looks like they didn't have the pinion depth set up correctly for however long they ran it. I think it looks serviceable though....