Hello! trying to identyfy what internals are in the differential I got with the car (MNR Vortx with Honda CBR1000) , I am confused, because to achieve
1 full turn of the wheel I need to turn the propshaft less than full 2 turns. It is approx 1 and 3 /4 or 4 / 5 turns.
In other diff I have spare , marked 3,92 it is almost 4 turns of the propshaft to achieve one full turn of the driveshaft flange.
I am confused because in all documentation (i.e. http://www.super7thheaven.co.uk/components/sierra_rear_differential/ ) the longest ratios that was
possible are 3,14 or 3,38. But nothing close to 2.
Does anyone know what it could be inside ? maybe there could be internals from some other car that fits sierra diff ?
The propshafts are also not the lobro joints type but the tripod type. Not sure if this is important. (just read that this tripod type joints are not
strong enough, but this is other issue).
Take the rear cover off, the diff ratio may be marked on the crow wheel. If not ,count the teeth on the crownwheel and pinion then divide the C/W by the pinion to get the ratio
1.7ish turns - presumably a 3.38
Don't forget that normally both wheels turn roughly equally. If one wheel is not turning, the other will turn twice as fast - so 1.7 turns for 1
rev of a single wheel would be 3.4 turns for 1 rev of both wheels.
[Edited on 25/12/20 by SteveWalker]
quote:
Originally posted by SteveWalker
1.7ish turns - presumably a 3.38
Don't forget that normally both wheels turn roughly equally. If one wheel is not turning, the other will turn twice as fast - so 1.7 turns for 1 rev of a single wheel would be 3.4 turns for 1 rev of both wheels.
[Edited on 25/12/20 by SteveWalker]
As stated, lock one wheel, other wheel in the air, turn the input flange and count the free wheel revolutions then work out the ratio. If you turn the shaft ten revolutions and count the wheel this will be more accurate.
Yes, but what SteveWalker just noticed - in the case of open diff one has to multiply x2 the wheel revolution .
Before I was playing with Westfield which has plate type diff , and when I was turning the propshaft - both wheels in the air was turning. So in this
case - 1 full turn of the propshaft was 3,92 turns of the wheel. (diff ratio was 3,92 for sure, it was rebuilded , teeths counted)
In the MNR I am working now, it seems to be equipped with open diff ( though the seller claimed there is torsen-type LSD, but it seems he was wrong)
, so one wheel was possible to lock easily and the other was turning while I was turning the propshaft.
So it looks like - with open diff- multiply x2 ; with locked diff - the ratio is the exact number of the wheel revolutions.
More correctly, the ratio is an average of that for the two wheels, so on the road, in a straight line, you will have two wheels each with a ratio of 3.38:1 or whatever; with one wheel stationary, you have one wheel with a ratio of 3.38:0 and the other with 3.38:2 (averaging to 3.38:1); and when driving around a curve, you will have two different ratios somewhere between those ranges, but again averaging to 3.38:1). Basically, for a fixed speed, one wheel slowing, means the other turning faster, but the average remaining the same.
If you jack both wheels and turn prop non-LSD will have wheels rotating in opposite directions, LSD both wheels rotate the same way. A Torsen or Quife ATB will need a slight tension on the wheels or it can free rotate the diff cage, the slightest of applied handbrake can allow the ATB to function. This has been known to happen when one wheel is on ice and the other on tarmac.
quote:
Originally posted by snapper
If you jack both wheels and turn prop non-LSD will have wheels rotating in opposite directions