--Quick Question-- About Wagon Springs

[gadget73]

I've done them with the jack under the control arm and the hammer method to separate the ball joint. I also stand in front of the car to lower the jack, just in case.

[saiyaneye]

Bringing this back to the top---
Another quick question though

For the rear I ended up getting MOOG 8795
Part Number 8795
Inside Diameter 5.000
End Type 1 Pigtail
End Type 2 Pigtail
Bar Diameter 0.625
Install Height 12.69
Load in Pounds 790.0
Spring Rate 182.0
Free Height 17.04
Rear Coil Springs
-----------------------
I have about 110 pounds in the trunk, give or take 10 pounds, what would be the best way to match up front springs so the car sets pretty level?

Front Springs:
Base: 374lb/in
Wagon: 443lb/in
HPP: 540 lb/in
P71: 700 lb/in

Rear Springs
Base rear coils: 107 lb/in
Wagon rear coils: 182lb/in
P71 rear coils 160 lb/in
HPP bags ~110 lb/in nominal

[mrltd]

Wiegh the car and determine the springs needed is the best way. Would help to have the rear hieght and how much the front needs to be lifted to sit level.

[saiyaneye]

Where to I measure, behind the wheel well or in front?

[saiyaneye]

I looked at blazes thread in readers rides and seen how he measured.

Rear sits up 11.75-12" (wow sits high.)

Front sits up 10.75" to 11"

[mrltd]

Hmm... well I guess some wagon springs would actually get it about level.

[1987cp]

might consider just getting some new cop springs, letting them take a set, and then trim them a little if they're too high.

[saiyaneye]

Front Springs:

Base: 374lb/in
Wagon: 443lb/in
HPP: 540 lb/in
P71: 700 lb/in

What springs could I get that would be about in between both base and wagon, I am thinking maybe about 400-415lb/in springs. That would probably be perfect seeing that I have 100+ pounds in the trunk at all times. If you guys need me to do anymore measurements I can't do any until Friday night I am in Colorado Springs at the moment, it is nice here but it is kind of cold and rainy.

[gadget73]

Stock Towncar springs are like 390 in/lb but they'll be slightly higher. If you use the HD sedan coils, you'll keep the same ride height and get the higher rate. I have them on my car, and the ride is anything but harsh. The change from stock rate to the HD coils is not enough to severely affect ride. Shocks can change it more to be honest. Actually on a Towncar, the HD coils make the front end a tad lower than stock since they have a slightly shorter free height than a Townie spring, and Lincolns have an extra front chassis brace and another foot of body hanging past the wheels.

[1987cp]

I'd not heard about Lincolns having an extra brace on the front of the chassis. Where is it exactly?

[saiyaneye]

So the rating has nothing to do with the height, I am confused? Is the install height all i have to worry about? How do I determine this if I am to choose different springs not listed on the list MrLTD posted?

[1987cp]

So the rating has nothing to do with the height, I am confused? Is the install height all i have to worry about? How do I determine this if I am to choose different springs not listed on the list MrLTD posted?

Abso-friggin-lutely. I schpealed a little on it on the thread by the new guy 911vic. The only book I've really read on the topic is one called "Chassis Engineering" buy a guy called Herb Adams. It was about 15 bucks at the local Schuler Books.

Spring rate is a measure of the resistance of the spring to compression. If a spring is rated at 500 lb/in, that means that a load of 500 pounds will compress it one inch. A load of 1000 pounds will compress it two inches. Spring rate is determined by a little formula that takes into account the diameter of the wire, the diameter of the coils, the torsional modulus for steel, and the number of active coils, and basically has nothing to do with the height of the spring.

Obviously, a 14" spring with a rate of 500 lb/in will compress to a length of 12" if a load of 1000 pounds is applied.

Spring height (free height) is just how long the thing is. This will generally change over time when a spring "sags", but the spring rate will not change unless one of the inputs to the spring-rate formula changes, usually the number of active coils in the event you cut a coil or so to make it shorter. This is why cutting coils will result in a slight increase in spring rate but sagging springs do not change the rate at all.

To make things even more fun, unless the spring is able to act on the wheel directly over the tire's contact patch, the effective spring rate at the wheel is less than the actual rate of the spring. There's a formula for that as well, but I'm not sure if anyone here has made the measurements required to put it to work on a Panther. If it happens, I'd guess Blaze86Vic would be the first to do it.

[saiyaneye]

So like gadget73 said, the shocks can/will affect the ride height as well. If they do would it probably be .25-.5? or less? J/w

Also does anyone here have damn near stock Vic or Merc w/ HD Coils on the front? If so can you take a measurement for me.

[mrltd]

He did not say it will affect ride hieght. He said ride QUALITY. Shocks have more to do with it than the springs.

[saiyaneye]

How much heavier is the station wagon up front? Is it much heavier?