901/07 questions

[targa6911s]

Hello,
Recently I´ve got a goal in having my Tach working (first time I see it working).
My next step was determining how well/badly it measures de real RPM.
With that in mind I have just looked at the type id numbers of the gear box of my 69 S, assuming they should be 901/10 but for my disappointment I found a 901/07 stamped and a sn - 7191179
Doing some searching (I did part of my homework) I found this places:

http://www.type2.com/library/misc/calcspd.htm
http://members.rennlist.com/chuxter/901&915ratios.htm
Speed vs RPM
http://www.roadglue.com/wiki/index.php?title=901_transmission
http://www.pelicanparts.com/techarticles/mult_tranny_ratios/mult_tranny_ratios.htm

I also have the Workshop Manuals

From all this places I could initiate from n A, F,M, U, ZD distribution, which in conjunction with the “multi trany ratios” table, allows me to confirm approximately (or not) both, the gross or fine accuracy of the Tach and also the mentioned original gear ratios.
Now, my questions are:
I didn´t find the 901/07 in the Workshop Manual (models 68,69,70,71), is this gearbox from another Porsche´s model (911 or 914)?
What other information can I get than the one previously mentioned?
Years of production?
Which was the aim with that gear ratios?
Is it rare or normal for this car and period; I mean, was it a normal option to the 901/10 or may it have been a particular order?.

Thanks in advance

[jpnovak]

The gears should be AFMSZ and this tranny was fitted from 66-69. The tranny number falls within the range for a 901/07.

[targa6911s]

Thanks Jamie,
Well, so the link "http://www.roadglue.com/wiki/index.p...1_transmission" is wrong.
Can you give me please some other link with accurate info on this matter?
Thanks
Ed

[jpnovak]

This info is from the factory listing of transmission numbers.

[targa6911s]

Jamie
Clear. AFMSZ and #´s match.
Thanks again
Ed

[Matt Monson]

Just one thing to note. 1969 was a slightly weird transitional year. You generally read that a 1969 911 should have a magnesium case gearbox. It was still a type 901 (generally a 901/13) even though it used the same design as the later 911 type gearboxes.

However, this is not 100% universal and early production cars under '69 model years (produced in the middle of 1968, the published transition date to mag case was 11/68) still had aluminum gearboxes. This is one of those early cars. I would not be concerned that this gearbox is not original to the car just because it's aluminum. The type number ( 901/07) is correct and as has been mentioned it's A,F,M,S,Z

[targa6911s]

Thanks Mat.