flyingmuffyn

Sorri if dis has been asked many times b4...can;t seem to find proper answers on the basics, juz reviews...

How do we calculate the Final Drive on the RX8 (or any car for dat better)? Its definitely not as simple as averaging the individual final drive ratios of each gear rite? I noe if u wan to calculate the Final Drive for each gear, u multiply the gear ratio wif the Axel Ratio....or sumthing lidat my maths is horrible...

And dis KS FD 4.777 kit is actually a sensor izzit? How does it work? it alters the Final Drive of the 8 to 4.777 : 1 thus shifting the Torque Curve lower for more blast at low revs?

apologies goondu here

coupe07

its a hardware gear.... not a sensor, bro.

flyingmuffyn

yah i realize its not a sensor...wuz hving a chat wif Darren on dis down at MG juz now...neither is it a gear....but its sort of some attachment mechanical device dat changes the ratios...wtf izzit?

cuscorex

to put tings simple:
1st of all,the oem final gears wich is 4.3/4.4 will b replaced fr INSIDE the rear diff housin.

then the theory goes: bigger the #;4.777 in tis case,better the "pull",but sacrificed on speed....(prancing horses & chargin bulls hv low finals,but they hv a powerful engine to compensate;hence they can hv high top speed.)

another eg:mayb u might hv encounter a incline tat u nd to dn to 1st,but aft the 4.7,u can actually attack it on 2nd,gt the hint?

tere's a table in vol127 of hyper-rev wich feature a comparison of the difference in speed wif a 4.4 & 4.7 @ the same engine speed.

flyingmuffyn

so its something mechanical that is attached to the rear differential? dis alters the ratios?

staticlag

It is a gear itself. You need to take apart 1/2 your car and take out your old gear in your rear differential (the thing that the rear axles are attached to) and replace it with a completely different gear. Take 1 look at my sig, the thing is huge and it weights like 15lbs.

staticlag

The way to find the final drive ratio of any gear is this.

jack up your car, put it in neutral. mark the driveshaft with a piece of tape, mark the wheels with a piece of tape. Then spin the wheel one full time around and count how many times the drive shaft rotates. That is your final drive. 4.77 means that the driveshaft needs to turn 4.77 times to turn the wheels once.

flyingmuffyn

thks!

now i noe the contraption is a Rear Differential Gear replacement...a bigger ratio will increase low-end torque cos the driveshaft nids to spin more times to turn the wheels once...

flyingmuffyn

one more qn...will the changing the rear differential affect the Limited Slip ability of the LSD?