need to choose a tranny for my 81 rabbit

[dino1]

So I pulled the motor from my beater 86 jetta, 1.6 na and I'm going to freshen up the bottom end, head, ip and injectors are freshly rebuilt. Plan to commute in the rabbit going 20 miles each way at about 70 to 75 mph. Plans call for a euro exhaust and downpipe and perhaps a veggie oil conversion. I have the choice of an FF tranny but not sure which year it came from and the AGS that was in the 86 jetta, which should I choose???

[BlackTieTD]

the AGS has a longer final drive but in practice the difference between the FF and AGS could be marginal. this will help: http://www.scirocco.org/gears/

[zukgod1]

See that's confusing.

I too have a FF trans and it looks like there are 2 different ratios on 2 different FF transmissions? Whats that all about?

I would like to take the 5th gear set I have (if it's a .71) and put it in my ACN trans. talk about tall geared.

Heck even adding a .71 to a AWY would be good.

Anyway, is there a date code we can look at to verify what year trans we are looking at?

[Quantum TD]

Here you go:

http://www.4crawler.com/Diesel/VW_020_transmission.shtml


Sadly, the FF will likely NOT fit into your 1986 Jetta, as it probably will not have the bosses on the outside of the diff. housing for the MK2 rear trans mount. There's a SLIM chance, that some later (1983-84) FF, FO, FN transmissions had the bosses, but they'd have to have the green cups on the output flanges to have the bosses. Personally, I've never seen one with the correct bosses.

Only the late 1983-1984 MK 1 transmissions will have the bosses, and they're usually the transmissions with the following codes:

7A
9A
4K
2H

All but the 7A would be useless in a diesel.

[RabbitJockey]

i had an ff and loved it.  good gearing for a diesel.  i like my 4 speed a lot as well, and i liked my automatic haha, i guess i like anything that has to do with a vw diesel.

[zukgod1]

Here you go:

http://www.4crawler.com/Diesel/VW_020_transmission.shtml


Sadly, the FF will likely NOT fit into your 1986 Jetta, as it probably will not have the bosses on the outside of the diff. housing for the MK2 rear trans mount. There's a SLIM chance, that some later (1983-84) FF, FO, FN transmissions had the bosses, but they'd have to have the green cups on the output flanges to have the bosses. Personally, I've never seen one with the correct bosses.

Only the late 1983-1984 MK 1 transmissions will have the bosses, and they're usually the transmissions with the following codes:

7A
9A
4K
2H

All but the 7A would be useless in a diesel.

That site contradicts the http://www.scirocco.org/gears/ site.
The site you listed only has one FF and scirocco has 2 FF's listed.

This is where my confusion comes from.

[AudiVWguy]

I,m running a 020 ACN (from a 1.8 gas 8v) in the caddy. I like the 3.667 final drive and the 0.745 fifth puts me about 2855 rpm at 70 mph. I put in the .71 and the rpm dropped to 2703. The problem was the motor wasn't in the best part of the torque band and the EGT's went up about 250 degrees more at the same speed. It felt like I was lugging the engine a little. I had to put the .745 back in and everything is better now.The reason I chose this tranny is cause 4th gear is great for the 45 mph range (a lot of streets where I live are 40-45). If you've built a strong, torquey motor this will work well.
--JB