Page 1 of 1

Changing transfer box ratios (hear me out!)

Posted: Sun Mar 27, 2011 3:41 am
by spandit
Was shooting the breeze with a friend yesterday and he mentioned that there is a conversion available for Land Rovers that change the high ratio in the transfer box for an even higher one. He made the valid point that in old Landies you generally start off in 2nd gear, which is the same for me in the Pinz, and most serious off-road stuff is done in low ratio, which is unaffected by the change.

So, can it be done, just change the high ratio cogs in the transfer box or am I missing something?

Re: Changing transfer box ratios (hear me out!)

Posted: Sun Mar 27, 2011 6:38 am
by undysworld
Robin,

I've never heard of it done in a Pinz. (I'm sure others can give you ratios and such.) Generally, I've heard of folks using a 710 xfer case to raise the speed of their 712, but you've already got a 710 xfer case I'd wager. Otherwise, there is the Executioner II gearing for the differentials. That's all I'm familiar with.

Regards,
Paul

Re: Changing transfer box ratios (hear me out!)

Posted: Sun Mar 27, 2011 12:30 pm
by Jim LaGuardia
It is not posible to change ratio's in trans or transfer case.
And the EX 2 diff(spider) gears are the same ratio as the originals, they are merely more robust and ride on bushings and improved pins.

Re: Changing transfer box ratios (hear me out!)

Posted: Sun Mar 27, 2011 12:45 pm
by spandit
Out of interest, why not possible? Could you not use gears with smaller teeth but same diameter?

Re: Changing transfer box ratios (hear me out!)

Posted: Sun Mar 27, 2011 1:54 pm
by Jim LaGuardia
Sorry, I don't have the time to go into such technical details, it would take too much time and webspace, but in short, for the transmission you would have to machine an entire new counter gear (cluster) and gearsets, but 5th is still DIRECT DRIVE. For the transfer case, the case dimensions will not accomodate input larger gearsets. So in short, unless you have access to big $$$$$, an expert machinist, a foundry, and a gear manufacturing facility it will not be easy.
It would be cheaper to just put in a TD transmission, but then you loose other atributes :(

Re: Changing transfer box ratios (hear me out!)

Posted: Sun Mar 27, 2011 3:12 pm
by Erik712m
Yeah not enough room. As far of fifth SoCal Was replacing third for fifth making a big gap in second and forth, the new third. Which blew up allot of clutches I've been told?

Re: Changing transfer box ratios (hear me out!)

Posted: Wed Mar 30, 2011 6:19 am
by TimJ
I was interested in this thread and a bit disappointed that there was no easy way to make a better highway truck then I saw this - http://cgi.ebay.com/ebaymotors/STEYR-PU ... 500wt_1182.

Has anybody had any experience with this and do you know what they are actually changing? It's a bit hard to get details from Australia unfortunately.

TimJ.

Re: Changing transfer box ratios (hear me out!)

Posted: Wed Mar 30, 2011 7:19 am
by Profpinz
It is not posible to change ratio's in trans or transfer case.
As regards the gearbox/transmission, I'd argue against that Jim.
It's a project I've been playing around with for over a decade and I'm not that far off a viable solution.

Without going into great detail the ZF S5-18/3 (Pinny gearbox) is not unique to the Pinzgauer....the ratios are, but the main casing (ie shaft centre-line spacing etc) are used in a quite few other vehicles in Europe (a specific Alfa, Vaxhaull, Opel, TD etc, even a Maserati) so other ratio clusters that would fit are available.
I've calculated that by using a combination of various gear clusters from different vehicles and by "changing" the selector pivot points (which are cast into the Pinny casings but not machined out) I can custom create a set of gearbox ratios more applicable to my 712 and it's use.
BTW....The first gear ratio used in the 710/712 is the lowest I've found in any vehicle.

Re: Changing transfer box ratios (hear me out!)

Posted: Wed Mar 30, 2011 11:52 am
by Jimm391730
I was interested in this thread and a bit disappointed that there was no easy way to make a better highway truck then I saw this - http://cgi.ebay.com/ebaymotors/STEYR-PU ... 500wt_1182.
Yup, the TD transmission. I'm using one in my 712W but with the aerodynamics of this particular truck the overdrive drops the revs so far that many people that have tried it have gone back to the stock tranny. The only saving grace I have is Jim L.'s 2.7 conversion, which gives back just enough addtional torque to match what is lost in the overdrive gearing. End result, I really don't go any faster than my stock 710 BUT the engine revs are much reduced (3200 rpm for 64 mph, basically half the speed).

The drawback is that 1st gear is a full 25% faster in this gearbox; even with the 2.7l conversion I really suffer in rough terrain. The gears are spaced further apart, so there is a longer "reach" between gears.

I, too, looked into what it would take to make the transfer case low range lower and high range higher, but in either case one of the two gears has to get larger and the T-case housing just won't allow room for the bigger gear (the other gear gets smaller to keep the shaft spacing the same, so that's OK).

Gear Vendors makes an overdrive/underdrive unit that would be very slick but they claim there is not enough room to put it in between the transfer case and T-case. Damn. It would give just enough overdrive to really match the speed and torque needs, and allow spitting ALL the gears.

Re: Changing transfer box ratios (hear me out!)

Posted: Sun Apr 10, 2011 8:34 am
by Lorenz
After decades regarding the Pinzgauer Scene and also a lot of friends in Graz who drove drove 712 Pinzgauers with the 710 TCase , my experience is to leave the TCase in the 712 like it is. If you don't go serious Off Roading you can transplant a 710 T Case, but with steep uphills and high altitude you will need the the 1. short Gear like it is original. With a 2.7Liter Conversation the 710 TCase fits better, but also the engine braking power on steep downhills is not as nice as with the 712 TCase. We use the 255/85 R16 BFG MT KM1 or 2 which makes the ratio also longer and Highwayspeed a bit faster.