Guys, I've been looking into getting a guard LSD recently and started thinking about possibly changing the final drive ratio as well to a taller setup.

I know I've seen people change individual gears IE 1-6 and know that the 1-3 shaft from the 997 has taller gears and a physically beefier 3rd gear.

Is it possible to simply change the final drive ratio? Let's face it, these cars are so under-geared especially when you're adding 200+ lb/ft of torque.

I imagine a taller final drive would make for a much more enjoyable car. Especially in the first few gears. On the high end, I imagine you'd get better gas mileage and spend more time in 5th at reasonable freeway speeds.

 

nice

 

It is a 3.44-1 stock. I would not touch that and would (did) touch the gear stack.

 

I would imagine changing the final drive wouldn't be too hard if you're changing out the LSD, but what are you going to do about the front differential? - I'm thinking if you ditched the front drive, it would be REALLY easy.

 

The entire trans needs to be taken apart to change the pinion and ring "king" gear. Only the side cover needs removal to install a lsd. Some shops even do the job with out removing the trans from the car. The higher ratio will make the jump from 1st to 2nd even more noticeable.

 

Tim are you running the 997 1-3 gears?

Please give more info

 

I ran two set ups moving to the 3rd. The box now has stock 1-6 but all steel caged needle bearing, steel syncro's and gt2 retainer plate. I plan on the 997 gt2rs gear set. I do have a motorsports 3.15 main shaft and lay gear that if I find a good second gear I may just throw back in there. 3.15 1st gives you 0-60 in one gear!

 

Who does all your work? I'm planning on building the tranny in my 996 GT2 and woudl like taller gears to go with the added power. Please get me the info ASAP as I'm hoping to commit to the project soon!

 

I do all my own work. I would call Brian @ bmc&g (740) 593-8936

 

I wish. Can you explain to me why something a like a 10% taller final drive isn't as good as changing all the gears? Financially at least, this seems like a good option. My main objective is to eliminate the really slow 1st and 2nd gears.

It seems like the car has way too much power to effectively launch. Most of the time you wheel spin into the rev limiter and have to short soft into 2nd...

 

Simple answer. They do not make one, only lower ratio sets. the right answer is 1st is way to low second is good the rest of the gear sets are good too. If you add 10% to the final drive you will add to the jump from 1st to 2nd making it worse. If you want add a taller tire for a quick fix, just match the fronts

 

My box is coming apart next week, what do you suggest I install for 1st & 2nd? 750whp

 

You will love a 3.15 first gear and second gears ratio is a good split of a 3.15 and 3rd. I would do also use a 997 3rd gear as its wider and stronger.

 

I am also interested about gearbox rebuild using new ratios, is there any info I might use or any builder I might ask, I mean something like all in one place