cutting coil spring

Help Support 7173Mustangs.com:

164runner

Well-known member
Joined
Dec 3, 2017
Messages
77
Reaction score
7
Location
US
My Car
73 mach1, medium blue, 351 C-6
wanting to cut 1/4 to 1/3 of coil off spring, noticed that the last 1 1/2 of spring is straight. there is a tab on the spring perch, where the end of the coil stops against it. question is cutting end of coil off, removes that straight section off the coil. will it still sit on spring perch correctly. tried to upload pic, it would not 

 
Joined
Apr 24, 2013
Messages
723
Reaction score
55
Location
SE MI
My Car
1971 J Code Mach 1
1972 H Code Mach 1
Kind of.

The 'tangent tail' of the OE spring is there so that the spring won't walk out of the lower seat as it's cycled. Is the cut spring going to move? Probably not. This is one of the reasons why most will recommend against cutting springs, if that sucker comes out of there it won't be fun...

If you are diligent when re-installing the springs I think you can get the newly cut end to touch the stop. I've cut the springs on a car many moons ago but can't remember if I just left the end out in space hoping it wouldn't walk or tried to get the end to the stop.

Sorry for the rambling, not really answer...

 

164runner

Well-known member
Joined
Dec 3, 2017
Messages
77
Reaction score
7
Location
US
My Car
73 mach1, medium blue, 351 C-6
i know a lot people cut there springs and put it back together and dont give it a second thought. but i am not one of them. for now i put it back together, do some research on a new set of coils

 
Joined
Sep 12, 2015
Messages
5,913
Reaction score
976
Location
SW Ontario
My Car
1971 Mustang Mach 1, M code, 4 speed.
Check with Eaton Detroit Springs. They have or can make what you want. Cutting a spring alters the spring rate. Buy 1" lowering springs at the correct spring rate you need for your car. You can call or email them and I'm sure they'll be happy to help. Also if you buy Eaton's, you know you have good US made product not some offshore junk. 

 

droptop73

Well-known member
Staff member
Moderator
Joined
Jul 5, 2010
Messages
6,541
Reaction score
277
Location
Grand Rapids, MI
My Car
73 Convertible
I have cut springs for our cars many times without issue over MANY miles of driving. The tab on the spring seat can be adjusted to meet the end of the spring as it's fairly thin and seems to act more as an index point rather than a stop. I typically measure the distance between coils with the car on the ground from the top of one coil to the top of the next. This will tell you how much cutting one coil or a portion of a coil will shorten the compressed height of the spring. This is not how much it will lower the car. Then I measure from the inner pivot of the control arm to the spring perch and from the spring perch to the center of the ball joint. this will tell you what the ratio is. For illustration let's say they are equal or 50%. At 50% a 1" drop on the height of the spring will yield a 2" drop of the ride height. This is very predictable and ride quality stays the same. The spring rate will rise slightly when cutting a spring. If the spring has 10 coils and you cut one off, the spring rate will increase by 10%.

Take it or leave it, cutting springs has been a topic of debate for as long as I can remember. This is just my experience.

 

luxstang

Well-known member
Joined
Dec 23, 2010
Messages
6,619
Reaction score
80
Location
Luxembourg / Europe
My Car
1972 Mustang Convertible
I’ve cut one whole loop off those one inch lowering springs from Mustangs Unlimited and I’ve been using the car as a daily driver during the summer months for about 8 years with that setup without any issues. You need to be careful to get the edge right when cutting them and of course you need to install them properly against the tab on the bracket. 

 

Latest posts

Top