Author Topic: 8 1/4 rear end strength?  (Read 8282 times)

Offline aris_unlimited

  • Project in full swing
  • Full Member
  • ***
  • Posts: 800
Re: 8 1/4 rear end strength?
« Reply #30 on: May 17, 2015 - 07:02:56 PM »
So if what I've found is correct, the lowest gearing ratio available for a dana 60 is 3.54:1. Which when doing the calculations on an rpm calculator puts me at about 2700 rpm, doesn't that seem a little high? I usually try to stick around 2000-2200 for highway rpm.
Cuda is gone :(

74 satellite, daily driver/project now




Offline Katfish

  • Resident
  • *****
  • Posts: 3733
  • 70 Challenger
Re: 8 1/4 rear end strength?
« Reply #31 on: May 18, 2015 - 08:28:04 AM »
Sounds about right, I have a Dana with 3.73s, hated it on the hwy.
With the 518 OD, it's now 2600 rpm at 80mph.


Offline brads70

  • C-C.com Expert
  • ********
  • Posts: 18747
Re: 8 1/4 rear end strength?
« Reply #32 on: May 18, 2015 - 08:37:17 AM »
I have an OD also but wished I had went with 3:73 in my Dana . Just because of the camshaft I chose, it's not "happy" at 60 MPH , 2000RPM's.



So if what I've found is correct, the lowest gearing ratio available for a dana 60 is 3.54:1. Which when doing the calculations on an rpm calculator puts me at about 2700 rpm, doesn't that seem a little high? I usually try to stick around 2000-2200 for highway rpm.
Yep that seems about right. I drove to Carlisle a couple times ( 7 hour drive) like that kept it around 3000 RPM's  I used to get 10mpg's at best with my old 440/727 now I'm getting 17 mpg's with close to 2x the power with my 451/4L60 combo.
Brad
1970 Challenger 451stroker/4L60 auto OD
Barrie,Ontario,Canada
Proud to own one of the best cars ever made!!!!!

My restoration thread 
http://www.cuda-challenger.com/cc/index.php?topic=59072.0
 My handling upgrade post
http://www.cuda-challenger.com/cc/index.php?topic=73985.0