diff ratio

[hotrod]

Righto I know about diff ratios and for every turn of the wheel the driveshaft rotates the number of turns to match your diff ratio!
heres the thing, have managed to snag some time to work on the van I picked up 4 months ago and thought I would check out the diff ratio while I had the arse off the ground, as when i bought it and was bebating wether to trailer it home or drive it, matey I bought it from said it was good for 80 k so I assumed it was a standard diff ( have since bought a modified one, just waiting for it to come from sydney on the cheap). Wheel rotates 10 times and the driveshaft rotates 20 & 1/2 times making me think what the!
Put the van on axle stands (as the van is unreg) and at reasonably high revs the speedo said 80 k, gave it one big rev and got it to 100k but wouldn't want to do that for an extended time period especially when you add in the aerodynamics of a brick outhouse.
Am I looking at things correctly?
and what the

[Warren]

going by thosr figures Hotrod its aprox 2.05 ratio doesnt seem right.

I think the original diff ratios were in the 4.00 4.5 range for the 80 kmh thing.

Have a look at the diff, where the pinion shaft goes into the diff, there should be a disc (large washer) there with the ratio stamped on it.

Warren

[ben]

the easiest way ive found.. cause i do it a bit lol.. love diff ratios! (only works on non lsd diffs which is almost all of em in beddys) is to jackup one wheel.. get someone to watch the wheel spin twice while you spin the tail shaft counting the no of turns.. so if the tail shaft turned 3 and a half to 2 turns of the 1 wheel then its a 3.5:1 ratio..

the reason for 2 turns not 1 is cause usually you would be turning the other wheel at the same time so it would be one.. this way you only have to jack up one wheel rather than 2!!

hope this helps..

hey hotrod what running gear you planning on running in front of that bargin of a diff?

ben

[hotrod]

So going by Bens theory I have a 4.00 (ish) to 1 ratio


Thanks Ben, am putting that bargian diff behind 173  3 speed at the moment, have done the v8 route but am at the stage of life where looking good is 9/10s of the enjoyment, and in a beddy how can you do anything but!

[ben]

sorry fella you wont be able to run that diff behind a 173.. not enough power to get ti moving moving! thats one of the reasons why it went cheap.. the average joe cant put it behind his holden 6 cause its too tall!! sometimes i think the 3.25:1 is too tall for my 173. and wasnt yours a 2.9:1?? definatly need a v8 to run that puppy!!

ben

[ben]

probably 4.2:1 then i think the swb came with..


post up a pic of your centre we will know exactly what it is by the look of it..

ben

[snow]

If your going to take of the back cover to have a look count the number of teeth on the crown wheel and the number of teeth on the pinon gear and divide the pinon into the crown wheel this will give you your exact ratio

For example on my beddy my crown wheel has 49 teeth and the pinon gear is 11
49 divided by 11 = 4.45

cheers snow

[ben]

hey hotrod what hjave you come up with regarding the diff and all??

cheers ben

[hotrod]

nothing yet!
as
wife broken
car broken
dog broken
New house (mortgage) broken
Too friggen scared to touch anything else this week

[ben]

bummer that doesnt sound so good..

hope it gets better fella!!

ben