901, 911, 914 Gearsets

[Scott Clarke]

N- $100
O- $100
V- $100 (I have two sets of V)
ZA- $100
ZD- $100

All in very good condition. Pictures on reuqest.

-Scott

[preS]

Scott,

If it's an original O 3rd I will take it. Please clearify.

Richard

[Scott Clarke]

It is an original 3rd gear O from a 914 gearbox. There is one person ahead of you. I'll let you know in the morning.

Thanks,
-Scott

[preS]

Hi Scott,

I pass, I made a mistake and am after an O for 4th.

Regards

Richard

[ajwans]

Please excuse my ignorance, what's the difference between O-3rd gear
and O-4th gear?

andy

[preS]

The ratio is the same but you can not use a 3rd for 4th or vice versa. An O for 3rd was used in the earliest 901/01 boxes, 64/65.

Richard

[jhora]

"O" Gear can be used for 3rd, 4th, or 5th gear in any 901 (911/914) transmission
Used in the 914-6 stock trans for 3rd and in the 911 Special transmissions:
"Speed" 901/78 as a 3rd, the "Airport" 901/77 as a 4th and the "Hill Climb" 901/81 as a 5th and in the 901/76,82,83....

[preS]

John,

Did you really try to install a 3rd for O on a 4th or 5th?? If so I would like to hear how you did it.

I am aware that a 3rd from a Sporto can be used for 4/5th in a regular box.


Richard

[Scott Clarke]

Correct me if I'm wrong, but I believe the issue with a "3rd" gear in the 4th gear position is that the thrust created by the heical cut of the gears is reversed. The bearings that resist the trust are only intended to work in one direction, so they are not loaded correctly with "flipped" gears. I seem to recal that this is OK for a race gearbox, but may be an issue for a street car where a single gear may see protracted use.

[ajwans]

OK, since we're talking about special ratio gearboxes can somebody
enlighten me. I have number 901/52 for airport gears, 901/77 seems
to be the same ratios but perhaps that is a magnesium case while
the 901/52 is aluminium.

Now, here's the mystery. Don@porsport had a 68 911 racecar which
had a 901/90, also purported to be an airfield ratio box, anybody know
what a 901/90 is?

The literature I have does not mention 901/90.

andy