Taller 5th gear, where to get one

[RabbitJockey]

the thing with short gear transmissions and our cars is that our engines red line at a low speed so the benefits of the short ratios aren't as productive with our cars, especially when you have a turbo

[Doakster]

Trans is back together with all new seals, a peloquin and 3.94 final. Also painted it machine gray. Going to try and get it back in the car tomorrow. Thanks for all the input fellas.

And thanks to Scott for sending me to George, what a stand up guy. I watched him reassemble the trans and learned a thing or two.

[tSoG-84bit]

crap, I've got a 4S sitting in my barn that I'd have gladly traded for a AVX... 

[janb]

crap, I've got a 4S sitting in my barn that I'd have gladly traded for a AVX... 

agreed, the AVX is 'gold' to auto-x.  Usually they will trade 2 good gas trannies for each AVX,

I use .71's out of older "A1" trannies, and really like a 9A w/ .71 for GTD driving, but I use ACN / AGS (Gas stock) for 'flatlander' 1.6 NA's or TD's in the mtn.

I would change the Eco Turbo to a 'larger' 1.6 turbo + an IP with Boost.  Should be able to find a package deal for under $500.

[Doakster]

Any idea what you guys think i can get for the 4.25 R&P that came out of my AVX

[larry104]

I have a 1992 EcoDiesel; Giles LDA pump, 2-1/4 in. exhaust, GTD intercooler and injectors, boost controller, stock K14 turbo. I sold the 4.25 R&P, found a .71 top gear and a 3.67 R&P and had http://www.aatransaxle.com/ rebuild it (the trans has worked flawlessly since rebuild 20,000 miles ago). The car was an absolute dog before the mods. It could barely hold 65 mph on even shallow grades. It now runs incredibly and easily pulls the taller gears. It'll smoke a Honda Civic in stop and go traffic and run comfortably all day long at 75 mph on the interstate. And, the best part: I get better mileage than before the mods. City, if I drive sensibly, returns 44-46 mpg. Highway with cruise control (Audivox setup -- love it) set at 65 mph delivers 48-50 mpg. Taller gears as part of other performance upgrades makes good sense. Stock, an Eco would have a tough time pulling taller gears, imo.

[Doakster]

I have a 1992 EcoDiesel; Giles LDA pump, 2-1/4 in. exhaust, GTD intercooler and injectors, boost controller, stock K14 turbo. I sold the 4.25 R&P, found a .71 top gear and a 3.67 R&P and had http://www.aatransaxle.com/ rebuild it (the trans has worked flawlessly since rebuild 20,000 miles ago). The car was an absolute dog before the mods. It could barely hold 65 mph on even shallow grades. It now runs incredibly and easily pulls the taller gears. It'll smoke a Honda Civic in stop and go traffic and run comfortably all day long at 75 mph on the interstate. And, the best part: I get better mileage than before the mods. City, if I drive sensibly, returns 44-46 mpg. Highway with cruise control (Audivox setup -- love it) set at 65 mph delivers 48-50 mpg. Taller gears as part of other performance upgrades makes good sense. Stock, an Eco would have a tough time pulling taller gears, imo.

That's some great feedback. Only thing i did at the same time as the trans mods was a 2 1/4in exhaust. I doubt that will give me much for now but hopefully a MPG or two. Maybe a giles LDA pump in the spring.

[larry104]

That's some great feedback. Only thing i did at the same time as the trans mods was a 2 1/4in exhaust. I doubt that will give me much for now but hopefully a MPG or two. Maybe a giles LDA pump in the spring.

It's money well spent. Giles knows injection pumps. I also had him do the VE pump on my 12V Cummins powered '91.5 Dodge pickup. HUGE performance gain. 

[ozzie]

Your conversation is over my head - I am not getting the gear ratios v. final drive, etc... 

I am interested in MPG (not preformance) in my 85 TD Jetta.  I have had the car for 14 years and recently lost 5th gear.  The trans case is in poor condition so I need to purchase a used trans.  I drive a ton at 70 mph.  Should I be looking for the AVX for the best mileage?  I am on a budget and want to avoid custom gearing.

[Rabbit on Roids]

an AVX is garbage for mileage. sell it to some racer on the whortex. it has 4.25:1 final drive. you will not get real real good mileage with an AVX. now if you put something with a .71 fifth gear and something besides 4.25's, it would work better. that is the lowest geared trans you could ever get in a stock VW. my AUG has 3.67 final drive gears and does fine on the highway.

[ozzie]

Thanks Kevin.  Good info.  I have an extra gasser trans and after searching the forum it looks like that might be an option to stick in there.  I will check the code see what the ratios look like.  lower rpm's will be good for the 'montana super 2 lane' highway driving  (70 - 75 mph).  thanks

[Rabbit on Roids]

if you want a really sweet trans, just swap in some 3.94 or some 3.67 final drive gears in there. its already layed out right gear wise, just needs taller final drive.

[Doakster]

if you want a really sweet trans, just swap in some 3.94 or some 3.67 final drive gears in there. its already layed out right gear wise, just needs taller final drive.

And that's exactly what these guys convinced me to do.

[ozzie]

The gas jetta I bought for the sheet metal (I hit yet another deer) has an ASF 5 sp trans.  That might work well for highway cruising.  The car was not drivable when I got it so I will have to look it over closely before I think about putting it in.

Doakster - are you happy with how things turned out with your trans?  And did you find somebody that wanted the AVX?  Swaping out the final drive might not be something I can do - I will read up on it this weekend.
Oz

[Doakster]

The gas jetta I bought for the sheet metal (I hit yet another deer) has an ASF 5 sp trans.  That might work well for highway cruising.  The car was not drivable when I got it so I will have to look it over closely before I think about putting it in.

Doakster - are you happy with how things turned out with your trans?  And did you find somebody that wanted the AVX?  Swaping out the final drive might not be something I can do - I will read up on it this weekend.
Oz

I actually haven't fired/drove it yet since the trans went back in. I was doing a bunch more parts at the same time for other stuff on the car and forgot a few things, hopefully it will be up and going by the end of next week.

I actually didn't take out the AVX, just swapped the ring and pinion out for a 3.94 ring and pinion, and put it back into. The R&P swap requires a complete tear down of the trans. When i pulled the trans to do my clutch it had a bunch of oil leaks on it, so i decided to put some different gears in there and a peloquin limited slip while it was apart.