Scot's '82 racer gets a ride hight adjustment by cutting springs!
05-13-2009 | 11:06 PM
#31
Instructor
Joined: Aug 2006
Posts: 232
Likes: 1
From: Melbourne Australia
I cant see the problem with cutting 1/2 to 1 coil out. It would be very hard to tell the difference from a stock spring and a cut stock spring when fitted to the shock!
Glenn
'81 928
Australia
Glenn
'81 928
Australia
05-14-2009 | 01:03 AM
#32
Captain Obvious
Super User
Super User
Joined: Aug 2003
Posts: 22,846
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From: Cambridge, Ontario, Canada
I remember years ago when the Mustang guys used to cut their spings. Every now and then, you would hear what happened when they caught air and the spring dislodged. I understand that we have coilovers but knowingly having a loose spring can be very dangerous.
05-14-2009 | 01:42 AM
#33
Former Vendor
Joined: Feb 2005
Posts: 15,230
Likes: 2,481
From: Anaheim
Now you are making me laugh! Have you seen how NASCAR guys change spring rates? 
Wedgies!!!! ha ha ha!
a spring is a spring. cut it and it is a stiffer spring, unless it is progressive, or has fitting issues at the ends that fit the purches. In the case of the 928 springs, they are configured in such a way that they can be cut with no adverse issues. In fact, there are very few springs that can be cut like this.
It just so happens, that the shock and spring package (peformance and stock) can be stiffened up with a shock coil spring cut. what you end up with, is a more optimal ride hight. (good). more adjustable ride hight (good), stiffer spring rate (good if you want this), and a fit that is transparant to the orginal design. (good). I cant think of any thing bad that could come out of it, especially if it was on a street car, besides, over powering the shock or too stiff a ride. (Both of which does not occur on the street or sport set ups avaible for 928s).
mk
Wedgies!!!! ha ha ha!a spring is a spring. cut it and it is a stiffer spring, unless it is progressive, or has fitting issues at the ends that fit the purches. In the case of the 928 springs, they are configured in such a way that they can be cut with no adverse issues. In fact, there are very few springs that can be cut like this.
It just so happens, that the shock and spring package (peformance and stock) can be stiffened up with a shock coil spring cut. what you end up with, is a more optimal ride hight. (good). more adjustable ride hight (good), stiffer spring rate (good if you want this), and a fit that is transparant to the orginal design. (good). I cant think of any thing bad that could come out of it, especially if it was on a street car, besides, over powering the shock or too stiff a ride. (Both of which does not occur on the street or sport set ups avaible for 928s).
mk
05-14-2009 | 02:38 AM
#34
Instructor
Joined: Aug 2006
Posts: 232
Likes: 1
From: Melbourne Australia
Cut Springs
Glenn
'81 928
Australia
05-14-2009 | 09:33 AM
#35
Drifting
Joined: Dec 2003
Posts: 2,902
Likes: 0
From: an unnatural suburban habitat
You can have your shock rebuilt to shorten the travel, if you have a rebuildable shock.
I have almost no pre-load on my 600/400 hypercoils to have decent ride height. If I were to go lower, they would be loose on full extension.
I have almost no pre-load on my 600/400 hypercoils to have decent ride height. If I were to go lower, they would be loose on full extension.
05-14-2009 | 01:45 PM
#36
Thread Starter
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Joined: Feb 2003
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From: saratoga, ca
as i said, fronts dont get disloged, at all . impossible. rears can happen, but it is absolutely preventable by ride hight adjustment. I had, and have no problem with a little looseness with the rear set up, as it is not loose enough to create any problem. PLus, in all the races scot has raced, he has had no issue, because there is no chance of an issue based on how we have it configured.
mk
mk
Mark,
This can be a dangerous setup. When the back goes airborn the spring will become loose and can dislodge/shift. Then when the car comes down on the shifted sping, it can get ugly really fast. This is the main reason cutting springs is illegal. Yes, nothing has happend to either of the cars yet but it could easily do so. You guys are playing with fire.
This can be a dangerous setup. When the back goes airborn the spring will become loose and can dislodge/shift. Then when the car comes down on the shifted sping, it can get ugly really fast. This is the main reason cutting springs is illegal. Yes, nothing has happend to either of the cars yet but it could easily do so. You guys are playing with fire.
05-14-2009 | 01:49 PM
#37
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From: saratoga, ca
TOTALLY DIFFERENT SET UP AND CONCERNS! with our coil overs and worst case possiblities, the bottom of the spring could hang on the bottom purch and be offset by .5", but that wouldnt have any dangerous outcomes. as I said, we dont adjust the set up so that can happen. 1 coil removal in the rear is max on the 928intl or stock spring set up. Very diffent than the american car spring shock set ups. not even comparable.
mk
mk
I didn't say anything about being able to tell. My concer is that when the wheel is in the air (0 weight on it), the sping should not be loose (a gap between the shock and end of the sping). There always should be pressure in the spring, even if the wheel is in the air.
I remember years ago when the Mustang guys used to cut their spings. Every now and then, you would hear what happened when they caught air and the spring dislodged. I understand that we have coilovers but knowingly having a loose spring can be very dangerous.
I remember years ago when the Mustang guys used to cut their spings. Every now and then, you would hear what happened when they caught air and the spring dislodged. I understand that we have coilovers but knowingly having a loose spring can be very dangerous.
05-14-2009 | 01:53 PM
#38
Thread Starter
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Joined: Feb 2003
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From: saratoga, ca
cutting a spring, using a wedgy, what is the differerence? You know there is none. You are increasing the spring rate by removing an active part of the spring. Wedgie does it by negating the effect of mid spring coils, cutting does the same at the end of the coil spring. PLUS, you are comparing apples and oranges. those springs are different in construction and configuration. the 928 springs can be cut to create a stiffer spring with no downside. other springs on different cars when cut could compromise the fit to the lower purch. on the 928 it is not the case. Dont make me post a picture of scots set up to prove you would never know by looking at the set up!
Yes, nascar has trailers of springs, but wedgies only increase spring rates and is adjustable. cutting is one way! wedgies are faster as well. cutting for us, is much cheaper if thats the way to go. always trade offs, right?
mk
Yes, nascar has trailers of springs, but wedgies only increase spring rates and is adjustable. cutting is one way! wedgies are faster as well. cutting for us, is much cheaper if thats the way to go. always trade offs, right?
mk
05-14-2009 | 01:57 PM
#39
Thread Starter
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From: saratoga, ca
DIng ding ding. we have a winner! exactly .
however, i would bet on coil in the rear and 2 in the front is max.
mk
however, i would bet on coil in the rear and 2 in the front is max.
mk
Thats cool, what I meant was some cars have tapered spring ends, the 928 has squared spring ends and have spring perches to match, that way you cant tell when one is cut. There would still be plenty of tension on the shock/spring assembly with a coil taken out. Maybe with 2 or 3 coils cut out, that may release all the tension when airborne I dont know, not game to try.
Glenn
'81 928
Australia
Glenn
'81 928
Australia
05-14-2009 | 02:00 PM
#40
Thread Starter
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From: saratoga, ca
I forgot about my set up. Im right with you there. my rears have some gap , because im at the very end of the travel. the fronts are a slight tight fit. with our hypercoils, they cant be cut, but the stock stuff can due to the way they are made and configured. there is no issue with my rears as there is no place for the rear sping to go but right as it was. I get air born on ocassion, and have no issues with the rears with a little gap.
mk
QUOTE=928andRC51;6566760]You can have your shock rebuilt to shorten the travel, if you have a rebuildable shock.
I have almost no pre-load on my 600/400 hypercoils to have decent ride height. If I were to go lower, they would be loose on full extension.[/QUOTE]
mk
QUOTE=928andRC51;6566760]You can have your shock rebuilt to shorten the travel, if you have a rebuildable shock.
I have almost no pre-load on my 600/400 hypercoils to have decent ride height. If I were to go lower, they would be loose on full extension.[/QUOTE]
05-14-2009 | 02:42 PM
#41
Nordschleife Master
Joined: Jul 2003
Posts: 7,674
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From: Minneapolis, Minnesota
The spring ends are square but the last coils are more tightly would to fit the slope of the perch. That's a difference. I'm not sure it's a problem but it does increase the force on a small part of the perch.
For really short springs that would come loose there are "helper springs." They're usually flat and are fully compressed when the car is on the ground. They extend to keep the spring from coming loose. Not sure if there are any for the 928 spring sizes.
For really short springs that would come loose there are "helper springs." They're usually flat and are fully compressed when the car is on the ground. They extend to keep the spring from coming loose. Not sure if there are any for the 928 spring sizes.
05-14-2009 | 05:53 PM
#42
Thread Starter
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Joined: Feb 2003
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From: saratoga, ca
The 928 purch has an angled reciever for that last coil end, not like the "standard" coil purches. so, when cutting the coil, it appears to be stock and doesnt create any issues at all. What you end up with, is a good fit, no slop and a lowered car with stiffer spring rate. NO downside, and no dissassembly labor or costs.
mk
mk
The spring ends are square but the last coils are more tightly would to fit the slope of the perch. That's a difference. I'm not sure it's a problem but it does increase the force on a small part of the perch.
For really short springs that would come loose there are "helper springs." They're usually flat and are fully compressed when the car is on the ground. They extend to keep the spring from coming loose. Not sure if there are any for the 928 spring sizes.
For really short springs that would come loose there are "helper springs." They're usually flat and are fully compressed when the car is on the ground. They extend to keep the spring from coming loose. Not sure if there are any for the 928 spring sizes.
05-14-2009 | 06:53 PM
#43
Instructor
Joined: Aug 2006
Posts: 232
Likes: 1
From: Melbourne Australia
Cut Springs
Fantastic, and the prize is.........the money or the dremel..... just kidding.
Thanks for the info on the cutting of springs Mark. A cheap and effective way to drop the nose on my 928 without any side effects.
It could only take a couple of hours to do, so it's on my to do list.
Glenn
'81 928
Australia
Thanks for the info on the cutting of springs Mark. A cheap and effective way to drop the nose on my 928 without any side effects.
It could only take a couple of hours to do, so it's on my to do list.
Glenn
'81 928
Australia
