Author Topic: Differential Questions  (Read 2841 times)

Offline msbaugh

  • Sr. Member
  • ****
  • Posts: 1148
Re: Differential Questions
« Reply #15 on: January 03, 2013 - 01:32:16 AM »
I keep saying 3.93... I don't know why I mean 3.91




Offline VTMopar

  • Sr. Member
  • ****
  • Posts: 1056
  • '70 Challenger Convertible, '74 Challenger Rallye,
Re: Differential Questions
« Reply #16 on: January 03, 2013 - 06:23:58 PM »
HP   Are those 3.23's in nice shape?   Do you know their history?   

I'd be very interested in what folks with a 440 and 3.55 gears gears are getting for milleage (I am planning on a road trip).   Also - what kind of rpms at different speeds?    Of course - tires matter - so that info too please :) 

Thanks
VT Mopar
VT MOPAR

Offline HP_Cuda

  • Hit the skinny little pedal on the right!
  • Sr. Resident
  • ******
  • Posts: 5268
  • Mopar or No Car!
Re: Differential Questions
« Reply #17 on: January 03, 2013 - 07:43:02 PM »

The 3.23 gears are in great shape I got them local from another Mopar guy. My machinist friend checked them out and gave a thumbs up, no scoring or mega wear issues.

I believe with the 3.55 gears and 28" tires like the 275/60/15 you would be doing about 3300rpm at 70mph.

Maybe some others would chime in.

B
1970 Cuda Clone 440 4 speed - sublime green
1970 Cuda 383 4 speed - yellow - SOLD

Offline Jamiez

  • Sr. Member
  • ****
  • Posts: 1981
  • Retro
Re: Differential Questions
« Reply #18 on: January 03, 2013 - 08:09:03 PM »

Offline brads70

  • C-C.com Expert
  • ********
  • Posts: 18747
Re: Differential Questions
« Reply #19 on: January 03, 2013 - 08:38:19 PM »
I'd be very interested in what folks with a 440 and 3.55 gears gears are getting for milleage (I am planning on a road trip).   Also - what kind of rpms at different speeds?    Of course - tires matter - so that info too please :) 

Thanks
VT Mopar
Lots of variables to consider , cam, carb, convertor slipage, etc, .... my old 440/727 got 10 MPG's with 3:55 and 255/60/15 tires
My new 451" with 2X's the power with OD 4L60 and 3:55 Dana so far is getting 17 mpg's  ( same tires)
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