Board logo

Diff ratios
Rob E - 3/10/10 at 03:27 PM

ashg - 3/10/10 at 03:28 PM

very informative post

jacko - 3/10/10 at 03:53 PM

quote:
Originally posted by Rob E

Yes lots of them

Rob E - 3/10/10 at 04:59 PM

Sorry not sure what happened its only showing what i put in for subject odd, anyway i wanted to know what the best ratio is for a 2.0 zetec, at the mo i have a 3.92 and want to fit an lsd any help would be appreciated.
Rob

interestedparty - 3/10/10 at 05:22 PM

quote:
Originally posted by Rob E
i wanted to know what the best ratio is for a 2.0 zetec,



Depends on the intended use. If the maximium speed of the car with the current ratio is as high as you want, or the car is able to, go, then if you want maximium performance you already have the best set up.

If however the revs for the speed ou want to go when cruising in 5th are too high, then you need a lower ratio. Tell us a bit more about your usage and you may get some helpful suggestions.

snapper - 3/10/10 at 06:51 PM

There are spread sheets available the will allow you to match rev limits, diff ratios and tyre sizes.
Standard Zetec and a type 9 box will probably feel better on the road with a 3.6 but the 3.9 gives the edge for acceleration.

matt_gsxr - 3/10/10 at 07:46 PM

tyre diameter also affects your choice. Those big rapper 25inch wheels are going to be a bit different to the mini 10's.

I guess 13 or 15, but you get what I mean.

Matt

snapper - 3/10/10 at 08:24 PM

And another though.......
The available standard gearbox's are to wide so your diff choice makes the lower gears to short or the higher gears to long, I struggled (still am) with getting a compromise, settled on a 3.9 and worked on the engine to get an extended rev range, basically I can rev the nuts off in first and still be in the torque when I hit second