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Nicholas R
08-07-2012, 06:06 PM
Does anyone know the diameter of the differential ring gear in the DeLorean transmission? I've been running some torque/hp numbers through the transmission with a guy at work but one key element that I dont have is the dimensions of the differential. I know the ratio is 3.77:1 but thats it. I really wish I would have measured while I had the transmission apart.

Does anyone know this information or have a transmission apart enough that they can measure it?

For reference, this is what I need the diameter of:
http://i565.photobucket.com/albums/ss94/NicholasRoedl/DSC_02461600x1200arrow.jpg

Thanks a lot!

David T
08-07-2012, 08:10 PM
You should also have the number of teeth on the pinion and the crown wheel. If you are going to calculate the #'s at the wheels you also have to know the wheel's true diameter.
David Teitelbaum

Nicholas R
08-07-2012, 10:33 PM
Already have those. Luckily I have good photos of each from when they were apart. 32 teeth on the ring gear, 9 on the pinion. Also I was wrong, we dont have the 3.77:1 ring gear, we (supposidly) have the 3.44:1. Still, the math for 32 teeth and 9 doesn't really work out. Simply put, 32/9=3.55 so maybe the ratio isn't exactly 3.44:1?

Either way, still looking for the diameter. There's a torque relationship I want to work out.

EDIT:
After doing more research, the DeLorean differential (assuming it's the 3.44:1) should only have 31 teeth not 32. The photo I'm counting from is from the back side but I still definitely count 32 teeth indications. Kind of odd.

jawn101
08-07-2012, 11:00 PM
Nicholas, I don't know if this will help but here's a more "dead-on" shot of my differential. I don't have the measurements you're after unfortunately.

http://dmctalk.org/attachment.php?attachmentid=12374&d=1344394784

dmc6960
08-08-2012, 01:01 AM
If there are 32 teeth, then wouldn't there only be 31 depressions for the 9 teeth on the pinion to sink into?

DMCMW Dave
08-08-2012, 09:28 AM
185 mm +/-

Nicholas R
08-09-2012, 11:29 PM
If there are 32 teeth, then wouldn't there only be 31 depressions for the 9 teeth on the pinion to sink into?
No because it's a ring, not a rack. There's no extra tooth like on the edge of a rack, there has to be the same number. Still puzzling. The documentation even says it should be 31x9 but I definitely count 32.


185 mm +/-
Thanks Dave! Hmmm... not as big as I was hoping for. I was hoping for at LEAST 8".