Coilover help.

bruce 1 · Oct 7, 2017

I have a 2006 TJ it is stretched coilovers and 41.5 tires.
It has fox 2.0 16 inch coilovers on the front. With PAC springs 16 inch 100 and 18 inch 150 . Jeep was perfect, but I have added a 5.7 Hemi to it and it was enough weight to set it down on the bump stops. I have tried to look up how much more the Hemi weighs over the Jeep 4.0 motor., but have had many different numbers from 50 pounds more to 150 pounds more.
What springs do I need to get my ride height back to the way it was?
Thank you Bruce

bgredjeep · Oct 7, 2017

You can check your weight using the springs you have. Remove the 100s, run the preload down, then see how many inches it compresses your 150s. Compressed inches x 150 is your corner weight.

From that you can figure out your new spring rates.

mac5005 · Oct 8, 2017

Here is an excel file I created to check spring rates and actual sprung weight at the shock using preload.

Directions are in the file, pm me if you need help with it.

http://metalwerxdesign.com/files/springcalculatorv2.xlsxhttp://metalwerxdesign.com/files/springcalculatorv2.xlsx

If you have more that 2" preload to get correct ride height, you need stiffer springs, if you have less than 2" preload you need softer springs.

mcutler · Oct 8, 2017

Re: Re: Coilover help.

mac5005 said:
Here is an excel file I created to check spring rates and actual sprung weight at the shock using preload.

Directions are in the file, pm me if you need help with it.

http://metalwerxdesign.com/files/springcalculatorv2.xlsxhttp://metalwerxdesign.com/files/springcalculatorv2.xlsx

If you have more that 2€ preload to get correct ride height, you need stiffer springs, if you have less than 2€ preload you need softer springs.

Link no good Scotty.

Simplifying from above. You can check it without taking any springs off. (You can also double check your work using only one spring like mentioned above, didn't matter which one. )

Using this chart, your combined spring rate is 60lb. Be sure you're at full droop with zero pre load and measure the overall length of the springs; then put the weight back on the springs and measure the springs again. Take the difference from the two measurements and multiply by 60lbs; now you have your corner weights.

That'll get you started. From there you can use some more math, or call Accutune or whoever and they can get you going from there.

Sent from my SM-G950U using Tapatalk

bgredjeep · Oct 8, 2017

Here's the spring rate calc I used.

http://www.crawlpedia.com/spring_rate_calculator.htm

ranger11 · Oct 8, 2017

mac5005 said:
Here is an excel file I created to check spring rates and actual sprung weight at the shock using preload.

Directions are in the file, pm me if you need help with it.

http://metalwerxdesign.com/files/springcalculatorv2.xlsxhttp://metalwerxdesign.com/files/springcalculatorv2.xlsx

If you have more that 2" preload to get correct ride height, you need stiffer springs, if you have less than 2" preload you need softer springs.

http://metalwerxdesign.com/files/springcalculatorv2.xlsx

TRD · Oct 8, 2017

I can help with a couple simple measurements, plus we have a ton of PAC springs in stock.

Just need to know preload or spring deflection, and shaft showing at current ride height & target ride height.