Spring rates! - TCCoA Forums
 
LinkBack Thread Tools
post #1 of 6 (permalink) Old 01-01-2019, 12:44 PM Thread Starter
Newbie
 
Join Date: Dec 2018
Posts: 3
Garage
Spring rates!

Hello I have been doing a lot of reading and only got so far. I am running a 97 t bird v8 auto in lemons. I found x5 rear shocks fit the rear and are really stiff. (Just a tech tip) I'm looking at spring rates right now.

I have some 900lb race springs I can fit in the rear and 650lb or 700lb for the front. Is that way too stiff?

I'm running what ever the stock sway bars are.

Front shocks will be the week point some new Sachs I got cheap on ebay for 25 each. But I will look into having them re valved or doing one of the many aftermarket front shock mods that are well documented on here.
Sexy jesus is offline  
Sponsored Links
Advertisement
 
post #2 of 6 (permalink) Old 01-01-2019, 12:57 PM
Road warrior extrodinaire

Super Moderator
 
Trunk Monkey's Avatar
 
Join Date: Feb 2006
Location: Home Sweet Home: Charlotte, NC
Posts: 11,777
Garage
Welcome.

Read through this thread for details. I've posted all the spring rates in post #4.

900 lbs is about 300% stiffer than stock. Yea, I'd say that's a bit much.

I see in your garage that you're a Lemons racer.

S4Gunn is also a Lemons racer. He could give you some suggestions. See the thread below for details.

https://forums.tccoa.com/26-racing/1...ace-tbird.html

Mods? Yea, I got mods ...
Air silencer delete, warp drive, dilithium crystals, flux capacitor, Slingshot Rubber band power adder, Moonshine & Gas, Leaf Blower Supercharger, Hamster Wheel & Hamster, Energizer Bunny generating 1.21 gigawatts, Mr. Fusion® Home Energy Reactor, hover conversion and a sextant celestial navigation system (The original GPS)
Best 1/4: 1,320 nanoseconds @ 670,616,629.2 miles per hour

"There isn't that much difference anymore between spacecraft, aircraft and modern automobiles..." - Keith Henry, NASA's Langley Research Center
See a list of my real mods and pictures of my car HERE. The true performance of my car was made possible by the Carolinas Crew Chief, RobertP at Rob's Tire & Auto

Last edited by Trunk Monkey; 01-01-2019 at 01:02 PM.
Trunk Monkey is offline  
post #3 of 6 (permalink) Old 01-01-2019, 01:54 PM
Seasoned PostWhore

Super Moderator
 
Join Date: May 2003
Location: Tinton Falls, NJ
Age: 37
Posts: 7,443
Garage
Send a message via AIM to MadMikeyL
I ran a Cougar in Lemons for several years, and we ran cut down SC springs and SC sway bars all the way around. We also ran the Tokico shocks in the front, and 03/04 Mustang Cobra Bilsteins in the rear. We also ran 17x9 Cobra R wheels with 275/40/17 Nitto NT05 tires, 13” Cobra brakes, and a bunch of chassis bracing, along with gutting everything we could to get weight out of it. With this combination, we were able to out-brake pretty much everything else on the track, and we could hang through the corners with all but the quickest Miatas and E30’s.

-91 Cougar LS, coming soon, complete overhaul with a 427" Windsor.
-90 XR7 5-speed black on black w/sunroof, MP2, coated rotors, double intercooler, 15%OD, ported heads, comp stage 1 cam, 85mm TB, 90MM LMAF, 80# injectors, and ported big valve heads
-98 Mark VIII LSC, Procharger P600b, TR3650 swap and 3.73s.
-90 SC Automatic rustbucket winter beater
-97 Tbird Sport 4.6 Nice weather daily driver
-"Your buddy Mike is INSANE!" -ClintD's dad
MadMikeyL is offline  
Sponsored Links
Advertisement
 
post #4 of 6 (permalink) Old 01-01-2019, 03:44 PM Thread Starter
Newbie
 
Join Date: Dec 2018
Posts: 3
Garage
hello! thanks for the replys. 300% stiffer is that correct? maybe my math is off. i was taking the larger number of the lx 501lb springs assuming the progressive portion of the spring is only the 1st 1" or so. and 900 is only 40% stiffer is that correct? then for the front it should be in the 600-650 range to maintain the same 40% spring rate increase. am I that far off here?

madmickey do you have any idea what your sc spring rates could have ended up at?
Sexy jesus is offline  
post #5 of 6 (permalink) Old 01-01-2019, 05:03 PM
Seasoned PostWhore

Super Moderator
 
Join Date: May 2003
Location: Tinton Falls, NJ
Age: 37
Posts: 7,443
Garage
Send a message via AIM to MadMikeyL
You could probably figure it out. I cut 1.5 coils off the rears and 2 coils off the front, so if you can find out how many coils the springs have from the factory, and the factory spring rates, you can multiply the spring rate by how many coils you had, then divide by how many are left, and you will have the new spring rate.

-91 Cougar LS, coming soon, complete overhaul with a 427" Windsor.
-90 XR7 5-speed black on black w/sunroof, MP2, coated rotors, double intercooler, 15%OD, ported heads, comp stage 1 cam, 85mm TB, 90MM LMAF, 80# injectors, and ported big valve heads
-98 Mark VIII LSC, Procharger P600b, TR3650 swap and 3.73s.
-90 SC Automatic rustbucket winter beater
-97 Tbird Sport 4.6 Nice weather daily driver
-"Your buddy Mike is INSANE!" -ClintD's dad
MadMikeyL is offline  
post #6 of 6 (permalink) Old 01-01-2019, 06:08 PM
Road warrior extrodinaire

Super Moderator
 
Trunk Monkey's Avatar
 
Join Date: Feb 2006
Location: Home Sweet Home: Charlotte, NC
Posts: 11,777
Garage
Quote:
Originally Posted by Sexy jesus View Post
hello! thanks for the replys. 300% stiffer is that correct? maybe my math is off. i was taking the larger number of the lx 501lb springs assuming the progressive portion of the spring is only the 1st 1" or so. and 900 is only 40% stiffer is that correct? then for the front it should be in the 600-650 range to maintain the same 40% spring rate increase. am I that far off here?

madmickey do you have any idea what your sc spring rates could have ended up at?
Well, for the base spring the differences are:

270 min to 900 is 233% increase in stiffness
330 max to 900 is 172% increase in stiffness

For the base rear springs at 349 min to 403 max you're looking at

270 min to 900 is 157% increase in stiffness
330 max to 900 is 123% increase in stiffness

I was looking at it as if:

270 min was 100%
540 min was 200%
and
810 min was 300%

So yea, looking at it that way, 900 is over 300% stiffer. But that's wrong. The above percentage increases are accurate.

Anyway, look at the chart in the other thread or just cut some SC springs like Mikey suggested.

Mods? Yea, I got mods ...
Air silencer delete, warp drive, dilithium crystals, flux capacitor, Slingshot Rubber band power adder, Moonshine & Gas, Leaf Blower Supercharger, Hamster Wheel & Hamster, Energizer Bunny generating 1.21 gigawatts, Mr. Fusion® Home Energy Reactor, hover conversion and a sextant celestial navigation system (The original GPS)
Best 1/4: 1,320 nanoseconds @ 670,616,629.2 miles per hour

"There isn't that much difference anymore between spacecraft, aircraft and modern automobiles..." - Keith Henry, NASA's Langley Research Center
See a list of my real mods and pictures of my car HERE. The true performance of my car was made possible by the Carolinas Crew Chief, RobertP at Rob's Tire & Auto
Trunk Monkey is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the TCCoA Forums 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











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



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 On
Trackbacks are On
Pingbacks are On
Refbacks are On

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