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Dual Transmissions
Posted: Wed Jul 28, 2010 4:46 am
by Willy Hilux
Has anyone read up on this setup? Sounds like it would give ya some gear selections and would be heaps lower gearing than dual transfers. It is just F%*king long.
So is anyone out there in Australia running this setup yet???
http://www.pirate4x4.com/forum/showthread.php?t=698521" onclick="window.open(this.href);return false;
http://www.pirate4x4.com/forum/showthread.php?t=132841" onclick="window.open(this.href);return false;
http://www.frontrange4x4.com/forums/sho ... nsmissions" onclick="window.open(this.href);return false;
http://bb.bc4x4.com/showthread.php?1123 ... sion/page2" onclick="window.open(this.href);return false;
Re: Dual Transmissions
Posted: Wed Jul 28, 2010 9:33 am
by yamaha__308
I reckon it's a bit of a wank.
Unless you were using two r-series boxes, it'd be pretty weak. When would you require that many gear selections anyway? Plus the issue of short rear shaft and looong front shaft, especially when used on a shorter wheel base. The shifter location would be a pain in the arse.
I would think dual transfers with 4.7 gears in the rear case would give plenty of choices and low enough. Easier, cheaper and stronger. Then you can upgrade output shafts if strength is still an issue and go twin 4.7's if you want lower gearing.
It is a cool idea though, and is something different, if that's all you after..
Re: Dual Transmissions
Posted: Sat Jul 31, 2010 5:00 pm
by a1 mech
interesting idea, shift on the fly wud be cool but thats about it for most situations. I run dual transfers with 4.7's in the rear case and thers more then enough ratios for everything Ive come across so far.
Stopping to go between ranges is a pain but unless ur competing who cares.
Re: Dual Transmissions
Posted: Sun Aug 01, 2010 10:38 am
by tweak'e
my father and his brothers made a farm hack back in their younger days with dual gearboxes. probably two 4 speeds. local guy machined an adaptor plate up. apparently it had a very short drive shaft and was only 2wd. but they used chains. a hell of a lot of fun on the farm !
one big plus was the 4 reverse gears
i wonder if you could use a van gearbox as they usually have rod/cable gear selectors on the side of the box.
Re: Dual Transmissions
Posted: Mon Aug 02, 2010 5:42 pm
by hillbilliywheelchair
sounds and looks cool
but i would start with a front wheel drive combo then a reversed and moded transfer (to equal out the internal diff of the motor box combo) then the 2nd gear box and with a few quick calculations it would only be 3 to 5inches longer than a standard combo
and have even more ratios than just 2 gearboxes due to the transfer on backwards between the 2 boxes
Re: Dual Transmissions
Posted: Mon Aug 02, 2010 6:46 pm
by bad_religion_au
a1 mech wrote:interesting idea, shift on the fly wud be cool but thats about it for most situations. I run dual transfers with 4.7's in the rear case and thers more then enough ratios for everything Ive come across so far.
Stopping to go between ranges is a pain but unless ur competing who cares.
ummm if you can drive, you can shift the transfer case on the fly...
Re: Dual Transmissions
Posted: Mon Aug 02, 2010 7:03 pm
by a1 mech
Well If u can shift twin geardrives on the fly buddy without grinding the shit out of them Id like to no a way.
Re: Dual Transmissions
Posted: Mon Aug 02, 2010 11:34 pm
by hillbilliywheelchair
a1 mech wrote:Well If u can shift twin geardrives on the fly buddy without grinding the shit out of them Id like to no a way.
easy (well use to be cant use legs now)its all about gear matching usualy 3rd+1st (in most standard transfer ratios) so flick from 3rd to 1st but at the same time change one of the transfers to hi
then continue thro the gears till you in third again and repeat it takes a bit of practices but if your used to a hi/low crash box you'll pick it up real quick
Re: Dual Transmissions
Posted: Tue Aug 03, 2010 1:36 pm
by oldmate
hillbilliywheelchair wrote:a1 mech wrote:Well If u can shift twin geardrives on the fly buddy without grinding the shit out of them Id like to no a way.
easy (well use to be cant use legs now)its all about gear matching usualy 3rd+1st (in most standard transfer ratios) so flick from 3rd to 1st but at the same time change one of the transfers to hi
then continue thro the gears till you in third again and repeat it takes a bit of practices but if your used to a hi/low crash box you'll pick it up real quick
going low to high is easy. high to low is much harder
low to high.
Say your running 4th gear at 40kph, low range, shift the main shifter into neutral.
with the clutch out shift low to high. should go straight in easy enough.
then cluch in, choose a high range gear (probably 3rd.) All the while you should be maintaing roughly teh right revs with the throttle to make it all smooth.
It's not an ideal setup. if you're going up an incline you'll probabyl loose enough speed to warrant going back to 2nd high. All because it takes alot longer to do.
Anyone here ever driven a twin stick mack?