gear ratio question
 

i was just wondering what the gear ration measured. correct me if im wrong but does the svx have 3.45 gears in it. what does that mean. if heard of some people changing them out to different ones and was currious as to what that entails.
thanks for teaching me something new about my baby.
jon

When we see 3.54 it's actually a ratio 3.54:1.

This means that for every 3.54 rotations of the driveshaft the rear axles rotate exactly once.

It's obvious that if you were to swap in 3.90's or 4.11's that would mean the driveshaft spins even more than the axles and therefore RPM's rise quicker with respect to speed. Acceleration benefits because the engine gets into power quicker.

thanks alot. im assuming that changing gears is a huge job and is generally not undertaken by alot of people due to the size.

it's a huge job mostly because the transaxle has to come out and part/all (don't know how much myself) of the auto box disassembled (the pinion gear has a long shaft going through the box)

I'm currently getting ready to try this swap, I have a Legacy tranny with good 4.11 gears and bad tranny that I'm gona swap into my old SVX tranny with a bad diff but good tranny. I'v been told that all you have to do is unbolt the front diff section from the tranny and that houses the ring gear and diff, then you take off the center diff section to remove a clip or nut that holds the pinion shaft in, then slide out the pinion shaft keeping all the spacers and shims in place to reinstall in to the SVX tranny. Then you just bolt the front diff section from the Legacy tranny on to the SVX tranny and your good to go. You should also replace any seals in between the diff and tranny sections or you may just end up with a junk new geared tranny. Also you have to swap the gears in the rear end, that is a little tricky becouse you will have to set the backlash and preload on the diff. It's not as scary as it sounds but should be done by someone who knows what their doing.

gears
 

Subafreak, I have been told by my subaru mechanic, that the transmission has to be completely dissasembled to install the ring and pinion. Because of this my next trans move will be to swap in a 97-98 outback trans with 4.44 gears,or a legacy with 4.11 gears. It would be alot simpler to change transmissions and rear end's, than the diss and reassembly of such a complicated transmission. If anyone knows for sure which trans is a bolt in, without re-wiring, please let me/us know. A gear upgrade would be the biggest bang for the buck we svx'rs could do. IMHO

I just took the tranny apart tonight. No big deal, it come apart like I said. The front diff section unbolts from the tranny, then you just unbolt the rear section, take the nut off the back of the pinion shaft and slide it out. Easy peazy:D

I wish I had known that. :(

When my diff went I was told, just like svxfiles, that it was a major task, potentially could have saved myself big bucks. oh well, live and learn, just wish the learning exerience on the SVX didn't have such a steep curve :rolleyes:

gear ratios
 

Subafreak, thank you for that info. Will you now have to swap out the speed sensors so that your speedometer and odometer is not off ? And won't the other differential bolt right up?

Re: gear ratios
 

The speedo is driven off the front left axle, so the diff ratio wont change it. The rear diff needs the ring and pinion gears replaced with the lower ratios to keep the same LSD center and the same half shafts.

Harvey.;)