ideal gear ratio

[bingen]

I am working on a '66 with a 289 and 3 speed. I plan to use 33" mud terrains on 15x10 rims and would like to know what would be an ideal gear ratio on the diffs for a vehicle that will see some trail where obstucles are mostly muddy conditions and not much rocks. The highway speeds will be something like 60 mph...

I have a 3" body lift on it now. I have not driven this as it wasn't running when I picked it up...so I have no idea how it runs.

 

[Bully Bob]

Great eng. & trannie for your needs.

(Your truck most likely has 411's now)

456's will get you (approx.) 2600 RPM @ 60 MPH with 33's ...& give you the "umph" for trail'n & mud.

---That would be my choice.---

Might consider at least a posi in the rear diff. (if it doesn't already have it) ......while your at it.

Also available., is lower gear ratio (the low range) for the transfer case.

$800-1000 (approx.) depending how much work you can do yourself.

HTH

B

 

[bingen]

That's what I was thinking...4.56. How about one of those EZ lockers with 33's?

Now that you say it may have 4.11's and maybe enough with the 289, I'm openning up the diffs (so I can clean them out anyway) and see what gears I have.

Thanks for the response

 

[Bully Bob]

You can find your ratio by marking the dr.shaft & tire.

Rotate the wheel 1 rev. & count the dr.shaft rev's.....4:11's =4.1 rev's ..... 3:50's=3.5 revs, etc.

 

[bingen]

openned up the front and found 12 teeth on the pinion and 42 on the ring gear...3.5:1 ratio?...

cleaned it out and sealed it up, put oil...run 31's for now or re-gear to....

Wana run 33's...

The rear diff didn't have the tag on it anymore.

 

[Bully Bob]

bingen..,

It's simple & you'll be better served if you fill in your sig. page with all you know about your rig & any mods & up-date it when needed...for obvious reasons. (info. page .., put your geographical area.)

Yep.., 350's