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What kind of getrag tranny is this?


dhr.vdw
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I read some topics about the Getrag transmissions on here but I do not really understand all of it. Can someone give me some info and specs about my transmission (I got it with my car)? It must be a 4 shift but I'm not sure, I read something about this guy explaining a 2 and 3 case transmission but I did not understand the difference although I can see the whole transmission differ from others of course.

Thanks, JP

Ps I hope the pictures are enough (clear), but let me know!

IMG_3913.JPG

IMG_3915.JPG

Edited by dhr.vdw
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If it were a 5 speed, the early ones have a 90mm long casting interposed between the main housing and the end cap (where the guibo goes); later 5 speeds have a one piece main housing but are still 90mm longer than the 4 speeds.  

 

FYI the early 2002 4 speeds with Porsche synchronizers use 8 bolt guibos--at least that's what my Feb '69 car (short neck diff) has.  The one pictured also has the heavier E21 tranny mount, a much better choice than the original 2002 mount.

 

mike

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The 4 speed is fine. Make sure that you have the right driveshaft for it. 

 

Synchronizers aka synchromesh are the parts of your gearbox that help with gear changes by matching the speed of new gear to the speed of the engine so you can change without making a scraping, graunching noise. The Porsche style are considered generally less robust than the later style. 

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The 4 speed gearboxes used the Porsche style synchronizers until late 1971 then they switched to Borg Warner style.  The B-W syncros were tougher and they also feel better (a bit more direct acting)  If you are going to use the original long neck differential and you have the correct driveline with 3 guibos you are fine.  If you are going to change to a short neck diff you will need to change the driveline and it will have a flange for a 8 bolt guibo. You may have trouble finding a 4 bolt flange for the back of that gearbox, the early boxes have a course spline on the output shaft the later (more common now) flanges are fine spline. 

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Alright thanks all!

I am building a racer so I would've prefered 5 shifts but 4 will do for now no problemo as this will be my first car so. Not much original stuff on this car.

I need something (4 shift is OK) low budget (I mean max 400 bucks) that can handle aggressive shifting and a rough drive style. Would you guys recommend using this tranny or get myself a new one and if so can I sell this (worth?) and what would be fitting and matching my demands otherwise?

Thanks in advance once again.

Cheers

 

JP

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Oh and I have no clue what a short neck diff and then I guess a long neck diff is..so I will just read a lot of stuff and deepen into this and I will send some pictures of my diff tomorrow as it's kinda late here. I got this diff with a special (I think custom for racing) welded on kind of scew that will let me adjust my springs I put on there. Things is the holders that should be in my wheel arch to 'hold' the springs are goe so I got no clue how it was meant.. I assume race gas springs that are adjustable as shock and sping in one attached to the diff..

Pictures will follow!

 

JP

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What kind of racing? The Porsche style syncro boxes WILL NOT SURVIVE "AGGRESSIVE SHIFTING" I would be surprised if the 1st and 2nd gear synchronizers were not already worn out in your transmission.  Just for your information depending on what 5 speed gearbox you are looking at the overdrive box has virtually  the same 1st, 2nd, 3rd and 4th gears.  5th is just 0.85:1 overdrive.  There is a close ratio 5 speed but they are hard to find and very expensive.   

Post a picture of your differential and we can tell you if it is a short or long neck.  It sounds like you are working with a lot of parts you have found that have never been all together at one time.  there is the possibility that some of them might not be compatible with other parts (long neck diffs don't fit on rear suspension crossmembers that are designed for short neck diffs for instance)

Edited by Preyupy
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Short neck differentials are just that:  short in length.

 

Long neck differentials are long and HEAVY.  They came standard in 2002's up until mid 1969.  The axles on a long neck diff car are also different.  The inboard joints look like U-joints.

Here is a rusty long neck diff.

IMG_7421.jpg

These pictures are of a 1968 1600 with long neck diff. Notice the axles.

IMG_5774.jpg

IMG_5771.jpg

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Alright, I got it thanks guys. Let me just get some pictures of my diff right now. I got what you said about not using the pors synchronizers only thing I wonder is you talked about 0.85:1 5th gear but that it close ratio right? Or am I getting this wrong? I try to understand all this technique lol, I read some google. But 1:1 is this closest ratio you can get so you have a good torque low revs and a good acceleration? Correct me if I’m wrong here. I’ll be back with pictures!
Thanks a lot!
JP


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Anything below 1:1 (ie 0.85:1) is considered an 'overdrive' gear and would typically be the 5th gear in a typical gearbox made for highway cruising. 1:1 is likely to be the 4th gear. 

 

Getrag also produced a now rare 5 speed, close ratio box with a dog leg 1st gear. This had a 1:1 5th gear with the other 4 gears underneath more equally spaced in terms of ratio so that you would be more likely to have a gear to hand better suited to accelerating out of any given corner. This gearbox is built for performance driving and not cruising. 

 

I an aure some some of the racers can describe the benefits of a close ratio gearbox better than I can. 

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Anything below 1:1 (ie 0.85:1) is considered an 'overdrive' gear and would typically be the 5th gear in a typical gearbox made for highway cruising. 1:1 is likely to be the 4th gear. 
 
Getrag also produced a now rare 5 speed, close ratio box with a dog leg 1st gear. This had a 1:1 5th gear with the other 4 gears underneath more equally spaced in terms of ratio so that you would be more likely to have a gear to hand better suited to accelerating out of any given corner. This gearbox is built for performance driving and not cruising. 
 
I an aure some some of the racers can describe the benefits of a close ratio gearbox better than I can. 

Overdrive as in, it would accelerate good as the ratio is beneath 1:1 so a good torque ideal for racing or am I getting this wrong? I do not really need a fifth gear if it’s gonna cost a fortune but a nice accelerating car with a good torque would be nice. Any recommendations or should I ask some racers? Oh and what is dogleg?[emoji28]
Thanks,
JP


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Have a look at the ratios for the various gearboxes in this spreadsheet. 

 

https://www.bmw2002faq.com/articles.html/technical-articles/engine-and-drivetrain/gear-ratio-rpm-speed-guide-r23/

 

Dogleg refers to the arrangement where 1st gear is left and backwards and all of the other gears are relocated compared to the usual arrangement (2nd is forward, 3rd is back etc). 

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