Shelp Drop Questions 65 Fastback??/

[347Fastback]

Hello everyone,

A part of my project is replacing the front suspension on my car. I would like to do the shelby drop and I would also like to know what springs go with this setup. Any info would be welcomed. I do have the template on the way from a friend. Thanks in advance...

 

[skywalker]

Stock springs will work, I personally have 620 1" drop coils.

IOW, pretty much any that would otherwise work for your car.

 

[2bav8]

I'm using 620 springs with my Shelby mod as well.

 

[NorCal66]

I'd say 620s too, it's a really nice look and handles very well.

The stiffness doesn't really bother me too much at all. Then again I pretty much stay in town, they might get to you after long trips?

You have a template, but just in case, or for more info, I used this:

www.thecarsource.com/shelby/restore/lowering.html

 

[TT670]

Im also using the GT springs from mustangs plus, IMO the 620 are just too stiff.

 

[dolfan87]

Hello everyone,

A part of my project is replacing the front suspension on my car. I would like to do the shelby drop and I would also like to know what springs go with this setup. Any info would be welcomed. I do have the template on the way from a friend. Thanks in advance...

I sent you a PM about some springs I have...disregard it, as I didn't notice you have a 65. Mine are for 67-70.

87

 

[HistoricMustang]

Ditto on the 620's for street use. When going to autocross or open track the 750's are good. For the crazy track stuff like Daytona I stick in the 1000 pounders.

Here is a question that will get a good argument going!

When you cut the springs, does the spring rate go up or down?

HistoricMustang
www.historicmustang.com

 

[Hack]

Ditto on the 620's for street use. When going to autocross or open track the 750's are good. For the crazy track stuff like Daytona I stick in the 1000 pounders.

Here is a question that will get a good argument going!

When you cut the springs, does the spring rate go up or down?

HistoricMustang
www.historicmustang.com

When you cut the springs, the rate doesn't change. Deflection = (rate)X(force)X(spring length).

A given force will deflect a unit length of the spring a certain amount. If you shorten the spring and apply the same force, each unit length of the spring still deflects the same amount as before. However, now the spring is shorter, so it deflects less than before.

So, your seat of the pants feel will be that the rate changed (the springs feel stiffer). However, the rate didn't change.

Did I pass the test?

 

[skywalker]

Ditto on the 620's for street use. When going to autocross or open track the 750's are good. For the crazy track stuff like Daytona I stick in the 1000 pounders.

Here is a question that will get a good argument going!

When you cut the springs, does the spring rate go up or down?

HistoricMustang
www.historicmustang.com

Should go down.

 

[skywalker]

When you cut the springs, the rate doesn't change. Deflection = (rate)X(force)X(spring length).

A given force will deflect a unit length of the spring a certain amount. If you shorten the spring and apply the same force, each unit length of the spring still deflects the same amount as before. However, now the spring is shorter, so it deflects less than before.

So, your seat of the pants feel will be that the rate changed (the springs feel stiffer). However, the rate didn't change.

Did I pass the test?

Under classic mechanics you'd be correct, but physics looks at things to ways: ideally and physically. With an ideal spring you'd be correct, but (I might be wrong) with a physical spring, I believe the cutting makes the spring rate go down. That's why people who cut springs tend to say they get poorer handling. There's a formula for it on historic's website IIRC.

 

[gp001]

I run the 620s as well. Not too stiff for the street in my opinion.

 

[skywalker]

I run the 620s as well. Not too stiff for the street in my opinion.

What shocks are you running gp?