anyone know of where i can get 4.7 or higher gear ratios for my RX7

 

damn, why the hell do you need gears that high?

You wont find it, you'll have to have it custom fab... from... a Ford 9" maybe???

 

im just looking for something to make my acceleration insane. so maybe not 4.7 but maybe 4.4 4.5ish


anyone out there?

 

Sylvain Tremblay of Speed Source makes custom ring and pinion sets for FC's. Available in 4.88, or 5.12 ratios.

I shipped my differential to him and he installed the set with a racing limited slip (clutch) unit. Total cost including shipping back to me was $ 1,100. Great quality work, have more than 5 years on it with no problems. Really helps out the acceleration. Engine revs faster. And my car goes through the gears faster. Don't expect great highway cruising with 4.88 or 5.10 gears.

I've seen other companies (2 others) that can do this for FC's. Can't remember their names though.

Sylvain Tremblay/Speed Source has been the dominant force in the IT classes on the East coast with his RX8 & FC RX7. I think he took the championship this year in his RX8 (Grand Am Cup Sport Touring Class). He also campaigns a Grand Am Porsche.

SPEED SOURCE
10870 NW 52nd St
Sunrise, Florida, 33351

phone : (954) 578-7071
fax : (954) 578-7057

www.speedsourceinc.com

 

damn 4.88 gears will rock. Tri-point cut gears last I checked.

 

Hi
glad I found this thread

was it a N/A rear you sent out?

 

i dont think there is a 4.7 u could do a 4.88 or a 5.125
give these guys a call
http://www.iscracing.net/axle.htm

 

**** dude, you'll probably have to shift into 5th on the 1/4 with that short of gearing...

What size wheels do you have? Larger wheels effectively makes your final drive taller.

 

a 4.88 gear with 225/45-17 which is only 1.2 % bigger in overall diameter then stock will go about 100mph in 3rd gear at 9k rpm. unless the car has been modified to have much more power then a stock or close to it, it wont hit 4th gear.

 

I emailed both companies listed
to make sure this $1,000+ custom installed sets
can be installed in a S4 Turbo II rear end



Tires I use in the back
are 26x10.5x16

i wonder In my case
for High HP turbo
thats into Drag racing
if i should pay the money for 4.88's

or just drop in some 4.30's

 

this is a mazdaspeed part, you simply extende the pinion shaft and vola 4.88
easy right...?

 

5.12... goodbye first gear ~rich