091 Gear ratios for Baja Bug

Storman

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Help I'm looking to figure out the best gear ratios to use on my baja build. I have an 091 ready for rebuilding and plan on having a 2180 motor and running 33" tires on the rear the car is fully caged and extended so it's pretty heavy. I'm new to this so any help is appreciated.
 

GDRBORETIRED

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Unless you are going to do it yourself why not discuss it with the builder of your choice? Most of them have lots of experiances with lots of options. Even if you do think you know what you want it would pay to at least listen to their suggestions.
 

DamnitJuice

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give Kevin at Trans West a call. he knows his stuff
(310)782-2413
 

cogbox

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a lot will have to do with if you will run this car on the street and off road or only off road. also what is your budget. at the very least i would put in:
-close ratio 3rd gear (around a 1.67)
-close ratio 4th gear (around a 1.35)
-billet 3/4 slider hub (stock ones are very prone to breaking)
-main shaft thrust plate (cheap improvement that works wonders)
-reinforce shift shuttle bracket
-steel shift ball
-pressure vent case
-bushed gear carrier
-new main shaft bearing
-new syncros
-super diff w vw "b" cover at the least
-chromolly pinion nut
this would be the least that i would do to get it to live for any real amount of time.
hope this helps in your quest:cool:
 

Jess@HighAngle

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I always heard a 4:86 final was strong- Jess
 

punchdrunk monkey

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On my VW Thing, I'm running a 091 behind a Turbo 2.5 Subie with 33" tires. The car will be street legal.

4.57 rp
3.44/2.25 mainshaft
1.39 3rd
.89 4th

4th is very tall for the highways. Here are the speeds/RPMs






1st 2nd 3rd 4th

5000 29 45 73 114
4500 26 40 65 102
4000 23 36 58 91
3500 21 31 51 79
3000 18 27 44 68
2500 15 22 36 57
2000 12 18 29 45
1500 9 13 22 34
1000 6 9 15 23


R&P 4.57
Gear 1.09 R&P= 4.86
Ratio= 1.00 1st= 3.44
Tire Dia= 33 2nd= 2.25
RPM= 0 3rd= 1.39
MPH= 0 4th= 0.89
 

punchdrunk monkey

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how do I figure out all the info posed above by punchdrunk monkey?
I'll send you a Excel spreadsheet to the e-mail address in your signature.

Darien
 

cogbox

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I always heard a 4:86 final was strong- Jess
the 4.57 is a stronger ring and pinion. using a 4.86 in a 091 trans would require you to modify a ring and pinion out of a 094 trans. so the stock 4.57 that comes with most 091 gear boxes would be better to use.
the 3rd and 4th gear ratios that i suggested would be best suited for a off road only baja.
 

Zac Reish

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i was told that the 091's with the thin ribs have a smaller r&p than a pyramid case 002. I learned this from wright gear box. Is this true?
 
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i was told that the 091's with the thin ribs have a smaller r&p than a pyramid case 002. I learned this from wright gear box. Is this true?
The Pyramid Case 002s were used in '73, '74 and 75 in the Camper (Combi Vans) and most of the Transporters. They had a 4.86 R&P. Before '73 the 002 came with four and then five rib cases that were not as strong and prone to flex under loads causing the pinion to "walk away" from the ring gear and cause breakage. These were the "thin rib" cases you refer to. These old 002s came with 5.38 and 5.42/3 ratios. Beginning in some '75 Transporters and on after that the 091 was used with a 4.57 R&P. All of the 091s had thick ribs.

At least that is how I remember it back in the day when I was looking for cores on a regular basis. There were all sorts of odd ball configurations around though including a "Mountain Gearing" that I don't remember. I'm sure there are some out there that know alot more than this, I have forgotten most of what I knew about them.
 

cogbox

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the way i know it goes like this:
*68' the worst idea vw ever had gear box( has acorn nuts around cv flanges) very weak and had problems with the pinion bearing clips walking their way off. 5.38 r&p
*69'-73' the "3 rib" 002 this was a great improvement over the 68'. but was built for a 1600cc engine. internals were the same as a beetle trans. 5.38-5.42 r&P
*74'-75' the "5 rib" 002 these gear boxes were a large improvement in strength over the 3 rib. a stronger r&p, gear set, and diff. 4.86 r&p
*76'-79' the "6 rib" or 091. this trans is sought after because of its strength. stronger r&p, gear set, and diff. but had a very weak 3/4 slider hub prone to breaking. 4.57 r&p
*80'-83' this is still a 091 "6 rib" trans. it is the same as the 76'-79' but shifted on the side of the nose cone. just below where the 76'-79' did. 4.57 r&p
*84'-up the 094 this is the big boy of the bus transaxles. the biggest improvement is the fact that it comes with a real reverse gear. roughly the same size as 2nd gear is. but it shifts on the side of the case, so shifters require a little work. 4.83-4.86 r&p

now of course as listed before by ramsey (you didn't forget much) there are a lot of ratios put in these transaxles for special areas of the world that required lower or taller ring and pinions. this is a short over view of the different bus transaxles made, there are other things that changed from year to year so don't get mad if i forgot something.;)hope this helps out
 
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Great review - sounds right to me. I know I have pulled several 5 Rib Pyamid 4.86 boxes out of '73 Combi Vans but never out of a regular Transporter, maybe because of the added weight they were the first to get them.
 

Zac Reish

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The Pyramid Case 002s were used in '73, '74 and 75 in the Camper (Combi Vans) and most of the Transporters. They had a 4.86 R&P. Before '73 the 002 came with four and then five rib cases that were not as strong and prone to flex under loads causing the pinion to "walk away" from the ring gear and cause breakage. These were the "thin rib" cases you refer to. These old 002s came with 5.38 and 5.42/3 ratios. Beginning in some '75 Transporters and on after that the 091 was used with a 4.57 R&P. All of the 091s had thick ribs.

At least that is how I remember it back in the day when I was looking for cores on a regular basis. There were all sorts of odd ball configurations around though including a "Mountain Gearing" that I don't remember. I'm sure there are some out there that know alot more than this, I have forgotten most of what I knew about them.[/QUOT[/U]

not all 091's came with thick ribs, i am under the impression that the ones with the thicker ribs have the largest ring and pinion. i have two different 091's one with the thick ribs and one with the thin ribs. rick at wright gear box said that the the thick rib 091's have the biggest ring and pinion. the thin rib 091 has wider gears than a 002 pyramid case however the the ring and pinion on the pyramid case 002 is bigger than the thin rib 091's ring and pinion. I don't know what to believe because i always believed that all 091's were the same. who know's the truth and can prove it.
 

cogbox

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the thickness of the ribs does not mean the ratio of the ring and pinion. there are 3 rib 091 boxes out there that are factory rebuilds from vw. the gear sets in all 091 are larger than the gear sets in the early 002 and late 002. the ring and pinions that are avaible in the 091 boxes are 5.38 (usually in the diesal boxes). 5.42 and 4.57. the 4.57 is the strongest that was stock. this is knowlege from rebuilding gear boxes for the last 15 years ;)
 

Zac Reish

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so than that would make sence that the 091's with the thinner ribs could have a smaller ring and pinion than a pyramid case 002. right?
 
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