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[Electric reverse] installing gear between differential output flange and output shaft/axle ??
reb - 10/12/16 at 09:25 PM

Hi,

I do not have any space in the transmission tunnel to install an electrical reverse between the propshaft and the differential input flange.

Is it possible to install the reverse gear between one of the differential output flanges and one of the output shaft/axle? So either on the left or right side.

I assume this should be problematic with open differentials but it should work with limited slip diffs.

What do you think?

[Edited on 10/12/16 by reb]

[Edited on 10/12/16 by reb]


CosKev3 - 10/12/16 at 10:16 PM

The car will hardly move, as the drive revolutions have been changed due to diff ratio


adithorp - 10/12/16 at 10:18 PM

Unless your electric motor has the torque to spin the wheel an open diff wont make any difference. The issue will be that having it on the diff input gives you the diff' ratio to help but on the output it's a direct drive... Electric reverse motors power can be borderline with the gearing; Without it might struggle.


voucht - 11/12/16 at 01:59 AM

Hi,

I think it is definitely possible. Check out what Rosco did on his Haynes, it might help (middle of this page):

http://forums.haynes.co.uk/showthread.php?t=13517&page=25

Rosco is very nice and helpful. I'm pretty sure you can drop him a pm to get in touch if you need more details. I guess he is also a member of this forum. If not, pm me and I'll get in touch with him for you.

You can also go through his whole build thread, just for the pleasure, his car and his work are amazing.

Good luck


reb - 11/12/16 at 08:09 AM

@ CoyKev3 and adithorp:

Thanks for your advise, it now makes sense to me.

So I would need a starter with 300% the torque if the final drive ratio is 3:1.


@ voucht:

Thanks for the link but Rosco installed his gear on the diff input flange. But I am speaking about the output flange.


@ all:

What about installing the reverse gear between the front and the rear part of the resilient propshaft?

The gearing would be correct but are there other problems associated with such a solution?


mark chandler - 11/12/16 at 08:28 AM

Use a winch motor on the back axle, they have compound planetary gears so lots of torque and wind slowly. EBay is your friend.


CosKev3 - 11/12/16 at 11:47 AM

quote:
Originally posted by reb
@ CoyKev3 and adithorp:

Thanks for your advise, it now makes sense to me.

So I would need a starter with 300% the torque if the final drive ratio is 3:1.


@ voucht:

Thanks for the link but Rosco installed his gear on the diff input flange. But I am speaking about the output flange.


@ all:

What about installing the reverse gear between the front and the rear part of the resilient propshaft?

The gearing would be correct but are there other problems associated with such a solution?


Will be fine as long as the propshaft can't move and cause clearance issues?

I know on my car using the Sierra centre bearing you can grab hold of the prop and move it quite a lot in all directions in the centre bearing