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diff ratio?

Posted: Tue Oct 12, 2004 5:19 pm
by UZJ40
what diff ratios should i use front and rear?

it is a 40, with 38.5" tryes and a 1UZ engine.
will be used for some competition and general play'n around

:?

Posted: Tue Oct 12, 2004 5:55 pm
by ORSM45
is it auto or manual?

id say go with crawler gears that reduce hi range by 8%.

thats because, 4.11s are cheap as chips, and if you bust one you wont need to search high and low for new ones.

the extra grunt will make up for the extra losses.

what sort of wheelin do you do?

Posted: Thu Oct 14, 2004 9:31 am
by dumbdunce
I agree, stick with the 4.1's and get your extra reduction in the transfer case. that engine will handle turning 38's with the slight underdrive from transfer crawler gears.

then when (not if) you bust diff gears, it's just a quick trip to the wreckers and you're back on the road. any other ratio it's a trip to the diff bloke and $$$. Also the taller the ratio the stronger the diff, so if you go lower, you are MORE likely to break them.

cheers

Brian

Posted: Thu Oct 14, 2004 9:53 am
by Shorty40
I agree.

I have a 40 with a V8 and find that the 4.1s turn the 38 TSLs no problem.

I thought about diff gears but ended up going the Marks transfer gears. The 8% underdrive helps a little aswell, not to mention the 68% in low :twisted:

It only costs a little more to do the transfr gears than setting up 2 diffs with 4.88s or whatever.

With the added benefit,as previously discussed, of being able to source 4.1s heaps easier :cool:

Posted: Thu Oct 14, 2004 10:46 am
by dumbdunce
Shorty40 wrote:...not to mention the 68% in low


not to rain on your parade, but the 3.08:1 is really only 55% reduction over stock (assuming you had the worst possible transfer ratio to start with, 1.99:1). I have no idea whre Marks get their 68% figure, I have asked them about it a few times on the phone and via email and they have always just ignored the emails or answered the calls with 'we'll get an engineer to call you back' - they never do.

to get 68% reduction the low range needs to be 3.34:1.

I still think they are a great product and have no problem buying and installing them, but I am appalled by their marketing and sales strategies.

get the gears, but do your own maths on what they reduction really is.

cheers

Brian

Posted: Thu Oct 14, 2004 11:13 am
by Shorty40
Noooooooooooooooooooooooooooooooooooooooo .............

Oh well, not that fussed about the numbers ;) I just know that it works well and is just about perfect for 38s :armsup:

Posted: Thu Oct 14, 2004 11:31 am
by dumbdunce
Shorty40 wrote:
Oh well, not that fussed about the numbers ;) I just know that it works well and is just about perfect for 38s :armsup:


exacly. the numbers don't really mean anything except for poseur value, it's just a shame they can't get their advertising straight.

Posted: Thu Oct 14, 2004 7:11 pm
by ORSM45
dumbdunce wrote:
Shorty40 wrote:...not to mention the 68% in low


not to rain on your parade, but the 3.08:1 is really only 55% reduction over stock (assuming you had the worst possible transfer ratio to start with, 1.99:1). I have no idea whre Marks get their 68% figure, I have asked them about it a few times on the phone and via email and they have always just ignored the emails or answered the calls with 'we'll get an engineer to call you back' - they never do.

to get 68% reduction the low range needs to be 3.34:1.

I still think they are a great product and have no problem buying and installing them, but I am appalled by their marketing and sales strategies.

get the gears, but do your own maths on what they reduction really is.

cheers

Brian


:lol: i would of never picked that, brian. you think about things too much ;) :lol:

BTW it is a bloody good question and well done for picking it.

transfer gears may cost more initially, but they wont bust as often as hi ratio diff gears.

Posted: Fri Oct 15, 2004 7:14 pm
by dumbdunce
383FJ45 wrote:
:lol: i would of never picked that, brian. you think about things too much ;) :lol:


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