Testing: Tire / Speedo / Differential Calculator - try it out!

[charles q]

Thanks for the help. No not 4.30. Changed out to 3.73 for the 7MGTE

[Deanfun]

Thanks for the help. No not 4.30. Changed out to 3.73 for the 7MGTE

Gah, what I wrote was confusing. I meant to say that your car came with a 4.30 stock, meaning that you'd have a 10/35 combination. This kind of sucks because you have to change both gears as opposed to just the easy one.

[Donn29]

What is the other gear, there is one at the end of the cable, are you talking about the one in the Trans?

[Deanfun]

What is the other gear, there is one at the end of the cable, are you talking about the one in the Trans?

There are two gears. One is located on the output shaft of the transmission, requiring you to remove the tailshaft to change it. This is the 10 or 11 tooth gear. The other (30-35 tooth) is just inside the tailshaft behind the 90 degree fitting that the speedo-cable threads onto. I believe this one is replacable be removing the 90 degree adapter and accessing it there. This is what I have been led to believe. Until I have messed around in there more, I won't say this information is totally correct. I plan on correcting my speedometer in the coming weeks, as I only have to replace the 30-35 tooth gear in mine to correct my ratio.

[swank]

Does the R154 use the same part numbers?

[Deanfun]

Does the R154 use the same part numbers?

That's a very good question. If someone can provide an answer... and the requisite part numbers if necessary, i'll include them (and the R154 final drive calculation) in the sheet.

[SupraFiend]

I'll look that up in my epc some time soon, but the comments for the 30-35 gears I looked up in the epc didn't list the MA70s so I'm guessing the answer is no.

[droptopsupra]

Very Nice.

Works great if you are swapping to a larger gear (numerically lower).

What if I go from a 3.73 to a 4.30 on a n/a car?

I will take a look at the formulas on the spreedsheet too.

Thanks!

[Deanfun]

Very Nice.

Works great if you are swapping to a larger gear (numerically lower).

What if I go from a 3.73 to a 4.30 on a n/a car?

I will take a look at the formulas on the spreedsheet too.

Thanks!

I've noticed it gets finicky when you get speedometer ratios on the high or low side of the available range. I'll take a look into it and see what I can do.

[1suprafan]

I'm not very good at reading your spread sheet. I have a 5 speed out of a 82 supra which came with a 3.73. I put the transmission in my 84 after auto swap but the rear end is still the 4.10. Could you tell me what I would need to do to get the speed right. Or would I need to get either a 3.73 rear end or a 4.10 transmission?