3.55 or 3.91

[Jon Melhuish]

My next question is which gear ratio would you guys go with 3.55 or 3.91
the car is 74 duster with a 340... 727 transmission...should be about 425 h.p.
I plan to drive it 3 or 4 days a week weather permitting.

 

[daredevil]

3.55 street gear 3.91 you hit the strip every weekend

 

[wish4hemi]

How tall are the rear tires? My car runs 3,300 RPM with 3.91's and a 27 inch tall tire.

 

[Jon Melhuish]

3.55 street gear 3.91 you hit the strip every weekend

Thanks

 

[Jon Melhuish]

How tall are the rear tires? My car runs 3,300 RPM with 3.91's and a 27 inch tall tire.

yeah , I didnt think about that....thanks

 

[SWETPT]

I was told that every 2" in height of the tire it lowers the gear by one, does that sound right.

 

[bpwordman]

3.55s will still give you good dig on the street, while keepin' the revs down at highway speeds; 3.91s will give you better 60ft.'s on the strip- which one means more to you?

 

[dgc333]

Randy's has a nice little calculator http://www.ringpinion.com/Calc_RPM.aspx that will allow you to see what rpm you will be turning at any give speed for different rear end ratios and tire diameters.

If you plan to drive the car 3 or 4 days per week you may want to consider 3.23.

I have 3.55's with a 27" tall tire but I also have an OD tranny so I can run 70 mph on the hiway and be turning just a tick over 2000 rpm. My Dakota pick-up has 3.91's and turns a tick under 2000 rpm at 70 mph but has 31" tall tires.

 

[stroked 340]

3.91's:-D:-D

 

[Jon Melhuish]

THANKS.......:love7: I love this site.