Tj coils, front to back - Off-Road Forums & Discussion Groups
Jeep-Short Wheelbase All discussion of short wheelbase Jeeps: CJ, TJ, YJ and JK

 
LinkBack Thread Tools Display Modes
post #1 of (permalink) Old 02-18-2003, 12:16 AM
Wrangler88
Guest
 
Posts: n/a
Tj coils, front to back

i know that a Tj's coils are smaller in the front and wider in the back, what happens if i put front coils on the back?? just wondering...
Sponsored Links
Advertisement
 
post #2 of (permalink) Old 02-18-2003, 05:00 PM
Veteran
 
MTPockets's Avatar
 
Join Date: Oct 2002
Location: Northern Indiana
Posts: 991
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: Tj coils, front to back

Your Jeep will go backwards in first gear and forwards in reverse. Don't do it!!

Not sure what would really happen, but I think the diameter of the coils is different, so they probably wouldn't fir correctly.

SRW
MTPockets is offline  
post #3 of (permalink) Old 02-18-2003, 05:18 PM
**DONOTDELETE**
Guest
 
Posts: n/a
Re: Tj coils, front to back

Why did you think of doing that? DO you need a set of rear springs?
Sponsored Links
Advertisement
 
post #4 of (permalink) Old 02-18-2003, 05:45 PM
Keyboard Implanted
 
JeepnGreg's Avatar
 
Join Date: Mar 2000
Location: Eureka IL
Posts: 4,676
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: Tj coils, front to back

well it'll probably ride really funny.....the stiffness of the springs si different....companys that make suspensions, lifts etc, usually matcha spring and shock to the weight of the vehicle to make sure its properly tuned. you can get a really goofy ride if your combo is over damped or under damped....


[img]images/graemlins/givemebeer.gif[/img] ====> [img]images/graemlins/40BEER.gif[/img] ====> [img]images/graemlins/thud.gif[/img]

edited: so basicvally what i was getting at is its a bad idea and you should prolly stay away from it
JeepnGreg is offline  
post #5 of (permalink) Old 02-18-2003, 08:49 PM
Official Curmudgeon
 
CJ7Taz's Avatar
 
Join Date: Nov 2001
Location: Kansas
Posts: 4,705
Thanks: 2
Thanked 5 Times in 5 Posts
 
Re: Tj coils, front to back

Bigger ain't necessarily better. I'd say the rears have a softer spring rate and would let the front sag.

Think about it, a coil is just a torsion bar wound in a spiral. The coils twist to compress. Given everything else equal, the larger diameter means more leverage and easier to compress. Wrap it into a 2" OD coil and it's almost solid. Wrap the same spring with a large enough diameter so I is a single coil, it's easy to compress.
CJ7Taz is offline  
post #6 of (permalink) Old 02-19-2003, 02:28 AM
 
Join Date: Dec 2002
Posts: 148
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: Tj coils, front to back

I have been studying coil springs for quite a while now for my custom coilover conversion (almost done).
2 factors are to be taken into consideration
1) Spring rate (measured in LBS/ Inch) which is how many Lbs does it take to compress the spring by 1 inch.
2) Load carrying capacity of the spring

It's a bit tricky to understand but both factors affect each other.

There are many variables that make a spring stiffer or softer...
1) diameter of spring wire
2) number of wounds (coils)
3) outer diameter of each wound
4) free length

here is a site with a formula to play with....

What you will need greatly depends on your particular application... For starters spring rate is lower (softer) in the front and higher (stiffer) in the rear. Front weight is constant, as opposed to the rear where load can vary... check out Old Man Emu's spring rates chart... if you have a winch, heavy bumper etc... u'll need a higher rated spring....

Angle is critical too.... It has to do with the forces under which the spring has to work.... Given the same vehicle with same weight, the needed spring rate will have to be higher the greater the angle in which it has to work. Check out the stock front coil spring in a suzuki vitara (a relatively light vehicle)... but because they are mounted pretty angled, their rate is double than if they were upright...

To get the rates right you'll need to known the following data"
1) total vehicle weight
2) front vehicle weight
3) rear vehicle weight
4) weight at wheel
5) unsprung weight (like springs, shocks, diffs, wheels and tires)...

It gets a bit more complicated [img]images/graemlins/smirk.gif[/img] if you want progressive or dual rate springs.... you can also try the formulae at SwayAway's website
There's a lot more to know ... be patient... and enjoy the ride.

And that was my 2 cents..... now someone [img]images/graemlins/givemebeer.gif[/img]

desertbuzz is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Off-Road Forums & Discussion Groups 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 email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome