why a shortened spring?
Thread Starter
Burning Brakes
Joined: Jan 2006
Posts: 761
Likes: 0
From: san jose California
why a shortened spring?
ok so EVENTUALLY i plan on putting some coys on my car, 18 x 9.5s in the rear, whatever backspacing i need.. i just picked up a 360lb fiberglass spring from vb&p... will i have issues later on down the road?
can you shorten a regular fiberglass spring?
thanks
can you shorten a regular fiberglass spring?
thanks
Safety Car
Joined: Nov 2008
Posts: 3,717
Likes: 551
From: Seattle Washington
I have Run 17x 11" Rims using offset Trailing arms. I have Shortened the Spring as well but I found I didn't need to as the 17" Wheels are Large enough for the Spring to fit up inside the Rim. You might have to turn the Spring Bolts up side down with the Nuts on top. Your 18" should give You more Clearance. A shortened Spring 1/2" off each side Pulls the Spring Bolts at an odd angle to where the Bolts starts rubbing the mounts and the Spring takes a weird Ark. I don't recomend it.
Melting Slicks
Joined: Dec 1999
Posts: 2,116
Likes: 156
From: Mid West
Cruise-In III Veteran
I have Run 17x 11" Rims using offset Trailing arms. I have Shortened the Spring as well but I found I didn't need to as the 17" Wheels are Large enough for the Spring to fit up inside the Rim. You might have to turn the Spring Bolts up side down with the Nuts on top. Your 18" should give You more Clearance. A shortened Spring 1/2" off each side Pulls the Spring Bolts at an odd angle to where the Bolts starts rubbing the mounts and the Spring takes a weird Ark. I don't recomend it.
http://www.vansteel.com/index.cfm?fu...p=1801&ID=2359
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
Yes, but the whole thing runs the gamut as to IF and how much...
first up is wheel diameter...if the spring edge fits inside the rim, not out...then if the wheel offset is stock and the rim width comes in toward the frame/t-arm/sway bar that with wider tires the first rub point is the Ebrake bracket on the t-arm...so once that is moved, dealt with, the wheel/tire is much closer to the inside by as much as 3/4 inch for the same wheel center line....
so if the wheel is 17" most springs have enough clearance to allow for spring straightening the arch...but that is only 3/4 inch to the inside...anything wider like could be done with eliminating the sway bar or offset t-arms would have to be gone over....
first up is wheel diameter...if the spring edge fits inside the rim, not out...then if the wheel offset is stock and the rim width comes in toward the frame/t-arm/sway bar that with wider tires the first rub point is the Ebrake bracket on the t-arm...so once that is moved, dealt with, the wheel/tire is much closer to the inside by as much as 3/4 inch for the same wheel center line....
so if the wheel is 17" most springs have enough clearance to allow for spring straightening the arch...but that is only 3/4 inch to the inside...anything wider like could be done with eliminating the sway bar or offset t-arms would have to be gone over....
Heel & Toe
Joined: Apr 2004
Posts: 15
Likes: 0
From: victoria bc
I have exactly the set-up you are going for in my `74 with the Coys and the 360lb spring. I used the 10inch bolts as this was the only way to get the car lowered sufficiently to get the right stance. Clearance to the edge of the inner rim from the nut is about 1/2 inch and i have had no interference issues. E-brake cable must be routed on top of trailing arm- no need to spend dough on ofset arms.
Thread Starter
Burning Brakes
Joined: Jan 2006
Posts: 761
Likes: 0
From: san jose California
I have exactly the set-up you are going for in my `74 with the Coys and the 360lb spring. I used the 10inch bolts as this was the only way to get the car lowered sufficiently to get the right stance. Clearance to the edge of the inner rim from the nut is about 1/2 inch and i have had no interference issues. E-brake cable must be routed on top of trailing arm- no need to spend dough on ofset arms.
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Le Mans Master
Joined: Apr 2001
Posts: 5,000
Likes: 1
From: Minneapolis, Mn USA
With 15s, spring contact, with a longer than the OEM 6 inch spring to trailing arm bolt, to the sidewall is a problem if your backspacing is 4.0 or greater.
With 18s, even with an 8 inch bolt to give you a lower ride height, your rear spring would perch inside your wheel. Your OK even if you increase the backspacing beyond 4.0, due to the larger ID of the wheel.
So in other words I dont believe you will have any issues with spring contact with 18inch wheel or tire.
Thats where I'm heading someday as well.
With 18s, even with an 8 inch bolt to give you a lower ride height, your rear spring would perch inside your wheel. Your OK even if you increase the backspacing beyond 4.0, due to the larger ID of the wheel.
So in other words I dont believe you will have any issues with spring contact with 18inch wheel or tire.
Thats where I'm heading someday as well.
Racer
Joined: Apr 2006
Posts: 429
Likes: 0
From: Marietta Georgia
You shouldn't need to shorten the spring for 17" or 18" rims. Typically an issue for wider 15" or 16" rims because the spring conflicts with the rim. I have 15 x 10" wheels w/5" backspace on my '74 and ordered a shortened spring from VB&P to make them fit.
I am in the process of adding rear coil overs so I can get more back space under the car.
I am in the process of adding rear coil overs so I can get more back space under the car.