Rear End Question

[Chryco Psycho]

70-74 will have the 489 , the E bgody was the last Mopar to use the 8 3/4 diff all other switched after 72

[cuda-cable]

as a reference, i've got a 73 cuda, has 3.55 sure grip and turns about 3000 rpm at 60mph with a 70 series tire.

[MJS73]

as a reference, i've got a 73 cuda, has 3.55 sure grip and turns about 3000 rpm at 60mph with a 70 series tire.

Good to know, thanks.  I'm running 60-series tires, but still...

Mike

[422STROKER]

I have a 26" tall tire and 3.23's and turn approx 2750rpm at 65.  Manageable for long trips.  I put the 29" set on and it dropped a couple hundred rpms(2500).  But I prefer to cruise at 70(3K rpms) since any slower may get you run over around here.LOL

Tom

[MEK-Dangerfield]

Ehh...with 26" tires, and 3:23's, I turn about 2500-2600 at 60MPH.

I think I'm in the same ballpark as Tom.   


  Mike

[MJS73]

I have 235/60-15s (26.1") on the back now.  I may go to 255/60-15 (27.1") come spring, so I should be good with a 3.23.  Tom, what rear gear are you running?

Mike

[MEK-Dangerfield]

I have 235/60-15s (26.1") on the back now.  I may go to 255/60-15 (27.1") come spring, so I should be good with a 3.23.  Tom, what rear gear are you running?

Mike

He said 3:23's also.   

[MJS73]

He said 3:23's also.   

Oops. Sorry. Thanks.

Mike

[422STROKER]

He said 3:23's also.   

 

I have a set of 255/70/15's but they are a bit too tall for my taste(29"), I bet the 27" would be good/better.

I used this calc to double check my post.

http://www.csgnetwork.com/multirpmcalc.html

Tom

[422STROKER]

Ehh...with 26" tires, and 3:23's, I turn about 2500-2600 at 60MPH.

I think I'm in the same ballpark as Tom.   


  Mike

Mike, I thought you had some 255/60s or 275/60s? 

Tom

[MEK-Dangerfield]

Mike, I thought you had some 255/60s or 275/60s? 

Tom

Tom,
 
  I have 255/60's on the back.

[422STROKER]

Tom,
 
  I have 255/60's on the back.

Those are 27's and would reduce the rpms lower than mine.  good size to shoot for.  I was going to try and find a 255/50/17 to get that height on mine.

Tom

[MJS73]

Thanks, Tom, that's a cool calculator.

Mike, do you have the 255s on 7" or 8" rims?

Mike

[VTMopar]

If you find a source for 3.23's, please let us know -- when I was looking last year, they were nowhere to be had.    Good luck

VTMopar

[Chryco Psycho]

a friend has a couple of good used sets of 3.23 available