[jetfireman]

Let me try to answer the question about rear axle ratios.
I’m not into the 61 that much but the ratios were the 3.08, 3.23, and 3.36. I can give you the standard and optional axle ratios for 62 and 63 and I think 61 would be about the same even though 61 had a 3 speed Automatic. Here is what I have for 62 Hydramatic.
F-85 (except 117 and 167) standard was 3.23 with or without A/C, optional expressway ratio was 3.07 with or without A/C, and optional mountain ratio was 3.36.
F-85 (117 and 167) standard was 3.36 with or without A/C, optional expressway and mountain were N/A.
F-85 (15 ” wheels) standard was 3.36 with or without A/C, optional Expressway ratio was 3.23 with or without A/C, optional mountain ratio was N/A.
Here is what I have for 62 Syncromesh.
F-85 (except 117 and 167) standard ratio was 3.07, optional expressway was N/A, optional mountain ratio was 3.36.
F-85 (117 and 167) standard ratio was 3.36, optional expressway was N/A, and optional mountain ratio was N/A.
F-85 (15″ wheels) standard was 3.23, optional expressway was 3.07, and optional mountain was 3.36. Now on the Jetfire I’m not sure but I think the standard ratio was 3.36.
Here is what I have for 63 Hydramatic.
F-85 (except Cutlass) standard ratio was 3.23 with or without A/C, optional expressway ratio was 3.08 and optional mountain ratio was 3.36.
Cutlass and Jetfire standard ratio was 3.36 with or without A/C, optional expressway and mountain was N/A.
F-85 (15″ wheels) standard ratio was 3.36 with or without A/C, optional expressway was 3.23, and optional mountain was N/A.
Here is what I have for 4 speed syncromesh.
F-85 (except Cutlass) standard ratio was 3.08, optional mountain ratio was 3.36, optional expressway ratio was N/A.
Cutlass and Jetfire standard ratio was 3.36, expressway and mountain ratio was N/A.
F-85 (15″ wheels) standard ratio was 3.23, optional expressway ratio was 3.08, and optional mountain ratio was 3.36.
Cutlass Coupe (15″ wheels) standard ratio was 3.36, optional expressway and mountain ratio was N/A.
Here is what I have for 3 speed syncromesh.
F-85 (except Cutlass) standard ratio was 3.08, optional mountain ratio was 3.36, optional expressway ratio was N/A.
Cutlass and Jetfire standard ratio was 3.36, optional expressway and mountain ratio was N/A.
F-85 (15″ Wheels) standard ratio was 3.23, optional expressway ratio was 3.08, optional mountain ratio was 3.36.
Now this is what I have and as you know options could and most likely did change during the year so you could have a ratio that is different than what I listed. I would have to say that the 3.36 was the most common ratio with the 3.23 next. I would also have to say that your transmission was changed at some point and they never changed the speedo gears or your rear end was changed and it was different than the original. I hope this helps you on ratios. Bruce

[jetfireman]

Hi Bruce,
I just read your questions about the exhaust. I have a Y pipe but the Jetfire didn’t have a Y pipe they just had a crossover pipe and the exhaust pipe came off the turbo. Mufflers are hard to come by. You can usually find one on e-bay. You should be able to get the pipes made at your local muffler shop. I have several mufflers but I don’t want to part with any at this time. The Jetfire muffler had smaller diameter tail pipes than the Cutlass muffler. I hope this helps you out some. Bruce

[jetfireman]

The 61 F-85’s were 3 speed Automatics, which have 3 forward speeds and 1 reverse. The 62 and 63 F-85’s were 4 speed Automatics, which have 4 forward speeds and 1 reverse. The shifts from 1st to 2nd were basically not felt when it shifted and you could feel the 2nd to 3rd shift and the 3rd to 4th shift.
The F-85 came standard with a 3 speed syncromesh transmission and the Automatic and 4 speed were options.

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