hello,
im not the best when it comes to mechanically minded stuff but i am unsure what all of the diff ratios mean. like some people have 3.45, some have 4.11.
whats the difference between different sizes and how does it benefit driving/racing?
am only asking coz i am still running my single spinner on my ef futura and wanna get LSD.
thanks guys
biff

basically waht it means is, say 3.08:1 which is standard diff ratio for manual futuras (i think)

it means for every one turn of the gearbox/driveshaft the wheel/wheels turn 3.08 times, or for 3.7's it means 1 turn of the driveshaft is 3.7 turns of the wheel. the higher up you go (which is actually termed lower diff ratio, wtf?) means your cars speeds in each gear drop, and revs out quicker, but gives you better acceleration. lower diff ratios decrease top end speed, but in a falcon 6 it doesnt really matter all to much, unless you have had massive work done you wont get over 180km/h on the strip!.

the cars speed at a given rev's will change once diff gears change. so say with me, auto, i had standard single pegger with 3.08 diff gears, i used to sit on i think around 1600 rpm for example at 100km/h. Now i have 3.7 dif gears and i sit on 2300rpm at 100km/h. The lower the diff ratio, the more petrol you will use.

higher ratios (2.9:1) for example, decrease acceleration, as it takes longer to rev out because you will get to much higher speeds in each gear, and will increase top end speed.

3.7 or 3.9 is the highest i would go. 4.11's are a waste of time and make your car a pig to drive.

3.08 diff gear mean for every 3.08 turns of the drive shaft there is 1 of the rear wheel. and so on and so forth through the different ratios

so... if i want better take off but not as much top end speed, i would wanna put in a diff with a lower ratio. correct??? if i already have a 3.08, what would u recommend i should put in and how much would it be?
thanx
biff

i stand corrected. got it mixed up, listen to this bloke, hes got the knowledge. my bad!



try a 3.45 (standard xr6) or a set of 3.7's. i doubt u will notice top end power loss with those ratios

lol, thats cool,
so from my standard 3.08 diff, what size should i be replacing with to get better accelaration with LSD?

Im also looking at replacing my standard 3.08 with either a 3.45 or 3.7 lsd. What's the easiest to source?

3.45:1 is the easiest one to fit. both are common though there is no speedo gear for ECU for the 3.7 to get correct speedo reading and shift points. with a 3.7 best of just relearning what the speedo is telling you

Looks like i'll be going with a 3.45.1 lsd - and you can get them from EF/EL XR6's right?

It would make and I6 a pig to drive no doubt, but its all horses for courses, on a higher reving motor with a matched cam, 4.11's can play the key part in a potent combination