Tire decision: 31 or 33? - Page 4 - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep CJ Forum > Tire decision: 31 or 33?

Savvy/Currie Aluminum Control ArmsROCK BOTTOM prices on LIFT KITS at Rockridge4wd!! WANT TO December Specials at Jeephut.com

Reply
Unread 01-14-2013, 01:24 PM   #46
BubbaK
Registered User
1983 CJ7 
 
Join Date: Jul 2012
Location: Ocean Springs, MS, MS
Posts: 203
Colt44.

1st gear in your Auto transmission is going to be (I can't remember exactly) a little taller than that of a 4 speed manual. So you're gonna need some help from gearing there. But your final gear, 3rd, should be 1:1 just like final gear in a 4speed manual. You could do a little more research on the Forum and find out exactly what you need to do. Or you might get lucky and get another response from Keith. As he said, he had a 4speed T-4 with 3.31's and 33's.

If I were you and running 32's, I'd consider a 3.54 or 3.73 gear ratio. That way you'd have ample power/torque on take-off and still have enough top end room to comfortably run at 65 mph without revving too* high. Good luck buddy. Let us know what you decide and how it works out.

'83 CJ-7_258 I-6_T-4_D300_AMC20/D30_Bone Stock

BubbaK is offline   Reply With Quote Quick reply to this message
Unread 01-14-2013, 01:44 PM   #47
Colt44
Member
 
Colt44's Avatar
1983 CJ7 
 
Join Date: Aug 2010
Location: Memphis, TN, Tennessee, USA
Posts: 483
Quote:
Originally Posted by BubbaK View Post
Colt44.

1st gear in your Auto transmission is going to be (I can't remember exactly) a little taller than that of a 4 speed manual. So you're gonna need some help from gearing there. But your final gear, 3rd, should be 1:1 just like final gear in a 4speed manual. You could do a little more research on the Forum and find out exactly what you need to do. Or you might get lucky and get another response from Keith. As he said, he had a 4speed T-4 with 3.31's and 33's.

If I were you and running 32's, I'd consider a 3.54 or 3.73 gear ratio. That way you'd have ample power/torque on take-off and still have enough top end room to comfortably run at 65 mph without revving too* high. Good luck buddy. Let us know what you decide and how it works out.

'83 CJ-7_258 I-6_T-4_D300_AMC20/D30_Bone Stock
Thanks, BubbaK - The tires I have on there right now measure 28" and I have enough low range power for my needs and I can run smoothly at 75 on the highway. My 4.2 runs quite a bit stronger since I put the 4.0 head and MPFI on it; maybe that has something to do with it. If I had 3.73 gears on there right now it would be like a jackrabbit off the line and probably peaking out too soon on the highway.

I think I'll probably be okay with 31s; I can re-gear later if needed but I don't want to wind up with granny gears if I go to low before I know what difference the tires make.
__________________
1983-91-94 CJ-7 Daily Driver
258 w/4.0 Head Conversion & MPFI
YJ OME Spring Conversion
YJ Interior, Metal Doors, Hard Top
Colt44 is offline   Reply With Quote Quick reply to this message
Unread 02-23-2013, 10:28 PM   #48
S76
Registered User
1984 CJ7 
 
Join Date: Nov 2012
Location: Stafford Springs, CT
Posts: 417
Guess I'm late to the party but I used this calculator to figure out what I wanted for tire size and gear ratio. There are others also.

http://www.4lo.com/4LoCalc.htm
__________________
If you always do what you've always done. You will always get what you've always got.
S76 is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools






Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.