Last year for 901 gearbox?

[hdavis]

Here's one for the gearbox gurus:

When was the 901 gearbox last used '69?

Did the 911 gearbox have the same shift pattern of the 901? (I know the 915 doesn't, but I'm not sure on the 911).

Thanks

Henry

[nick-moss]

911 box was fitted to the 2.2 in 70/71. It has a dogleg pattern like the 901

[hdavis]

Thanks Nick

[Scott Clarke]

Henry-
They were pretty much the same except for the ratios and the use of magnesiun instead of aluminum for the case. Also, the clutch was changed.
-Scott

[schmidt]

The last version of the type 901 was magnesium for all 69 cars except the early production cars and always in the early 69 Limited slip cars were aluminum. The new version of the limited slip which was larger, used stub axles, and most important used an ungulated disk for static proload did not come out right away. Thus for LSD cars early in the year 69 the aluminum box was used because the new magnesium would not work with the old LSD. The ratios for the 69-71 are the same, the pre 69 cars are different. The only difference in the case for the 901 vs the 911 case is the location of the more inbored location of the ball pin for the clutch fork in 69 and the different provisions for the push clutch vs the pull clutch. Lastly the 911 box use a shorter drive flange due the change in the spider gear arrangement for the open differential starting in the 911 box for 1970.

[hdavis]

Scott, when you mean the ratios, how were those changed. I had the chance to drive a 70E this morning, and I seemed to be going through the gears slower than in my 68. Like it was taking longer for the car to reach high revs. This is when I thought the 911 gearbox might not have had the same pattern as the 901.

Anyway, it has been a long time since I had driven a 2.2 MFI car, and I had forgotten how much "smoother" it is when compared to my 2.0 Weber 68S.

Thanks again

[Eric911S]

Hello: The ratios for the 69 car are A,F,M,S,Z and the ratios for the 70-71 cars is A,GA,N,V,ZA. I think the 68 cars were A,F,M,S,X(this is off the top of my head). A great street box is A,GA,N,S,Z with 225/50/15 tires. Thanks Eric

[schmidt]

As referenced in the previous post the 68 car would have different gearing, a hair shorter. A,F,M,S,X as compared to, off of the top of my head like, A,GA,O,V,ZA. Thats 2 ratios in second, 2 ratios in third, 3 ratios in forth, and 3 ratios in fifth. Iam not sure why you would think the pattern is different, the differences are explained in the previous post. The internals are the same, the 901 comes in aluminum and magnesium, the case is quite different, but the internals are close except the differential, and the most people would not be able to tell the difference between a 901mag and a 911mag cases. Only the casting number and the outward position of the clutch fork for the larger clutch are the differences.

[schmidt]

Eric you replied while I was typing, you are off on those first two ratios, I can double check my spec book, but I have them memorized. I used to carry every gear by letter and number for both 901 and 915 in my wallet and committed them to memory. None of my cars have stock gears, all have Factory special ratio gears and LSDs, Iam obviosly into gears.

[Scott Clarke]

Henry-
Others beat me to the ratio explaination. I'm re-gearing my type 911 to AFMSX, as I'm looking for more zip, and I'm using 195/65 tires. What do you mean by "smoother?" Is it a function of revs?
-Scott