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93-525i
08-25-2005, 10:08 AM
I know this has been discussed before, but I'm planning cutting a coil from my front stock springs and replacing the 9mm spring seat with the 3mm one. Does anyone have pics of their car with cut springs? How many coils did you cut? I'm curious as tot he drop per cut coil.

Thanks

liquidtiger720
08-25-2005, 10:14 AM
I think most people here would say. "Don't do it". I would agree with them. Exacly why are you cutting your springs?

93-525i
08-25-2005, 10:23 AM
The reason I chose to go this route is because I don't want the car too low and I also want to retais as much of the stock ride as I can. I ordered a set of BavAuto springs but canceled the order when I read more about them here. I think the key to cutting springs is to do it corectly, since the stock springs aren't progressive rate springs, the spring should not stiffen when a coil is cut. Looking at pictures of the stock spring, it also appears that the spring does not flatten out too much at the top or bottom where it seats, so no heating and bending will be needed either. I think it would work fine.

White535Mtl
08-25-2005, 10:36 AM
As liquidtiger mentionned,your bmw deserves much more than that. Don't try to save the extra buck and go get those springs.

ericcamaro
08-25-2005, 10:43 AM
cutting coils is a cheap and effective way to lower your car, but as soon as the springs start to wear out as you know they will they will start to sag and then your ride quality is all shot to ****. If your going to cut them you shuold take off maybe half to a third of a coil but before you do that you may just want to try the springs off a touring model or the m5 springs both lower the car a little bit (would be significant with the 3mm pads) and you will not jepardise the integrity of your suspension. if you decide to cut em I would have another stock set laying around when you change your mind.

tim s
08-25-2005, 10:46 AM
they claim their springs only drop about 1/2" & maintain a comfortable ride with better handling.
tim s.

uscharalph
08-25-2005, 10:48 AM
cutting coils is a cheap and effective way to lower your car, but as soon as the springs start to wear out as you know they will they will start to sag and then your ride quality is all shot to ****. If your going to cut them you shuold take off maybe half to a third of a coil but before you do that you may just want to try the springs off a touring model or the m5 springs both lower the car a little bit (would be significant with the 3mm pads) and you will not jepardise the integrity of your suspension. if you decide to cut em I would have another stock set laying around when you change your mind.
So M5 springs plus 3mm pads would lower the car how much?

DanDombrowski
08-25-2005, 10:54 AM
The spring will definitely stiffen when a coil is removed. How much? I have no idea (without analyzing it), but I do know that it will. There are some equations for determining the spring rate of a coil based on the diameter of the coil, length, end type, etc I have in some of my design books. Don't know them off the top of my head, but I definitely know length is a factor. Just throwing that out there.

632 Regal
08-25-2005, 10:54 AM
the ends of the springs ARE bent a bit where they seat in the pad, if you just chop them it will probably cut right through the primary seating area and youll get metal to metal in a short while.

93-525i
08-25-2005, 11:01 AM
I'm not trying to go the cheap route, I don't mind buying the springs, it's the ride quality that I want to save.
Here is my other car, and as you can see all performance, not much ride quality :)

http://home.comcast.net/~polosport8/P1010009.JPG

brodee
08-25-2005, 11:03 AM
So M5 springs plus 3mm pads would lower the car how much?

On the touring I got almost an inch with m5 springs and 3mm pads.

Incantation
08-25-2005, 11:16 AM
i read you want to retain your stock ride.. chances are after 12 years your springs and shocks are shot anyway so "stock ride" is not happening.. go get the sachs kit.. nice lowerage, and it rides almost stock.. but firmer

bimmerd00d
08-25-2005, 11:19 AM
As someone who has been through this, I would say do NOT do this. Get yourself a nice set of BavAuto, or H&R springs and the stock Boge shocks. You will hate the way the car sits with cut springs. You will eat up your tires VERY VERY quickly too by cutting stock springs.

DaCan23
08-25-2005, 12:00 PM
A friend of a friend once cut his springs... if he hit a really good bump the spring would slip out of the mounts and would have to take it apart to reseat. Never a good idea.

93-525i
08-25-2005, 12:07 PM
A friend of a friend once cut his springs... if he hit a really good bump the spring would slip out of the mounts and would have to take it apart to reseat. Never a good idea.

Cutting one coil form the springs will not allow it to jump out of it's seat, even if hitting a bump fairly hard. These springs, even without one coil have so much preassure pushing into the seat it's not possible unless I cut like 3 coil off. I've done it before on another car and without a problem, and I know a couple people have on this board as well and have had the setup for several years before going to aftermarket springs.

93-525i
08-25-2005, 12:36 PM
Anyone have a used set of Bav Auto springs they want to get rid of?

Kalevera
08-25-2005, 07:28 PM
Alright.

Let me say it frankly, because it needs to be said -- cutting springs or using BavAuto springs are just about the dumbest ideas I've read in a long time. I feel so strongly about this topic that I'm tempted to use a few choice foul adjectives to describe all related subjects...

I once had an acquaintence who bought a 525 for his wife off of a kid. The kid had cut the springs (stupid kid). On the way home, the driver hit a mild bump (California highways) and the subframe split in two.

Cutting the springs would leave me no choice but to classify the cutter as an idiot...and I don't like to write people off as such.

For myriad reasons, using bavauto springs is for dingos, as well. Not as dumb as cutting springs, but good lord, man....you've been warned. The garbage will bottom out like there's no tomorrow. Especially if you're running stock shocks, and if you're trying to buy a used set of springs, I have a feeling that's the case.

Look, it took me a few months to learn it, as well, and I can practically guarantee that my car looks worse than yours so you actually have a reason to do it right the first time around -- *DON'T* do things on the cheap. If money's an issue, SAVE the pennies. Doing it cheaply the first time around only cost me more money in the long run.


best, whit

genphreak
08-25-2005, 07:40 PM
**very well said** Whit, and to think a set of Voigtland springs are only $200, are progressive rate and fit straight in... why do it the hard way. Saving is easier... ;) GP

uscharalph
08-25-2005, 07:45 PM
I'm with Whit! I'm trying to put what I'd like to do to my car in some sort of order by priority. What needs to be done gets done first. Get the most bang for my buck, but do it right the 1st time or wait.

darron525
08-25-2005, 07:49 PM
as stated before, get m-tec springs and 3mm spring pads.


darron

Bimmerman
08-25-2005, 08:52 PM
Stealer here wants $392 each for front and $349.20 for rear m tec springs, works out to around US$1125 for all 4 springs just to buy them. gotta convince BMA to set up here in oz...

Kalevera
08-25-2005, 08:56 PM
BMA's prices, were they doing business in Australia, would be equivalent to the dealer's (albeit slightly less). Your government levies hefty taxes on importing such items. Hence it's more expensive.


best, whit

genphreak
08-25-2005, 09:36 PM
BMA's prices, were they doing business in Australia, would be equivalent to the dealer's (albeit slightly less). Your government levies hefty taxes on importing such items. Hence it's more expensive. best, whit I disagree a little on the numbers Whit, its generally 17% (inc. consumption tax) on the full import value . It works so that (mainly) American car companies and thrrough suppliers can continue to build cars here despite the fact that it is not economically viable to do so on the wrong side of the world. They like duties as they not directly show up like policy thorns in the country's account balances.They want to support the industry, but they don't want anyone to know how much the policy rallly costs, and in effect the consumers here subsidise local industry every time they import something, which we should.

The problem is, Australian stealers (inc. FoMoCo, GM, Toyota etc) stealers all hike their parts prices to be competitive on cars that noone wants due to the ongoing automotive market glut.

Mitsubishi is having a hard time atm giving 5 year warranties and cheap prices. All the rest have bastardised price points too. The only place they feel they can cash in is on parts, which is very disorganised here and run by the mafia in a big way.

The locals have little idea about marketing them to anything other than the panel shops and motor-trade. However there are more back yarders in Australia than in most places. We have two main parts enterprises and a gaggle of euro-specialists, but its like the choice of whtehr you want to do business with a middle-eastern street-gang or your regionally-appointed central european mafia.

The mainstream places won't help if its not a domestic car or a $2 chinese tool. We do need a bma.com.au down here... and the prices would be 15%+costs, so you could say it'd charge customers a 100% markup (it would only operate on a relatively meagre 'Australian' scale) and still do a nice (if small by US standards) business. :) GP

Kalevera
08-25-2005, 10:17 PM
This is getting O/T but...

Nick, although I never mentioned any numbers, it's important to remember that the US Dollar is stronger than that of the AUS. The 25% or so weakness (I forget the exact number...been a while since I had to concern myself with the exchange rate) adds cost across the board. The argument correlates to the Euro as well, and BMW is decidedly a company that operates on it.

US prices on parts are affected in a manner tantamount to the AUS/US rift; in the past six months, BMW has implemented across the board price increases to dealers and other wholesalers, citing exchange rate discrepancies. Of course, the added cost gets passed onto the consumer.

The most ironic item that I know of in this foray is BMW Cool Blue, which is produced in the US and theoretically shouldn't be affected by the exchange rates. What was previously a $17/gal item is now a $25/gal item.

Now, as I've hopefully implied, I know very little about international finance, and beyond finishing one course short of completing an econ minor in college (sorry sorry, university :D), ignorantly little about exchange rates. Given that preface, I do know that when our cars were new, they were sold at an additional 100% of the US price (again -- it could've been from government luxury tariffs, exchange rates....I don't know but I doubt the latter). Specifically, the 750 was a $100k US car and a $200+k AUS car.

Secondly, I did a cursory investigation into developing some kind of import/export operation myself. I mentioned it to my boss, who is Australian, and he indicated that he'd looked into it -- that is, importing parts through his family -- but found it to be not economical.

Times may have changed, but given my general incredulity of bureaucracy, I highly doubt it ;)

best, whit

pyro
08-26-2005, 01:20 AM
Where and how much $$ are the m5 springs? Im also looking for a very suddle drop in ride height? How much do they usually lower the car?

Nick.Hay
08-26-2005, 03:42 AM
Be very careful, as you may be cutting the exact same off the springs, but they may differ in the final result...

I'd be more inclined to buy a 'proper' set of lowering springs... but thats just me. Nothing but the best for my E34 :D

Good luck, but "don't get out the angle grinder" is my suggestion.

genphreak
08-26-2005, 09:08 AM
This is getting O/T but...

it's important to remember that the US Dollar is stronger than that of the AUS. The 25% or so weakness (I forget the exact number... I do know that when our cars were new, they were sold at an additional 100% of the US price (again -- it could've been from government luxury tariffs, exchange rates....I don't know but I doubt the latter). Specifically, the 750 was a $100k US car and a $200+k AUS car.

Secondly, I did a cursory investigation into developing some kind of import/export operation myself. I mentioned it to my boss, who is Australian, and he indicated that he'd looked into it -- that is, importing parts through his family -- but found it to be not economical.

Times may have changed, but given my general incredulity of bureaucracy, I highly doubt it ;)

best, whitThanks Whit, you raise good points there. In the case of parts the prices here are not subject to luxury car taxes or any tariff above 10%. After we a few years ago introduced the GST we got rid of sales tax (20-30%) on some items in favour of a 10% consumption tax on all items (except foodstuffs). You are right though- at the moment the exchange rates are working well for us. At present the Aussie Dollar (AUD) is 0.75 to the USD and that is nearer the AUD 0.80 level we had prior to our new tax regime. Before the Afghanistan war it had dropped to AUD 0.60 levels (for some time)- i have a feeling that might be what turned your boss off...

However my point is not so much that the financial argument makes it viable against the competition, it is how the marketing/business one does. No-euro parts vendor here even has an online catalogue. Plus now with the recent free-trade agreement, any American made parts can be imported without any tariff whatsoever. (Not that there are many on a bimmer, but TRW and some others do make a few in the US) :) GP

93-525i
08-26-2005, 10:07 AM
Hey guys, well again, I didn't do this to save a little money, didn't try to be cheap, I just wanted the stock ride and after cutting one coil off the springs, I got just that, a car that sits 1 to 1.5 inches lower and the ride is exactly the same as stock. I drove around after I put the struts back in to let it settle, and than I wen to a parking lot to go through some speed bumps to ensure that it would not have any consequences. The car rides great, no improvement in handling and there was none expected as the BMW already has pretty good handling as a stock car. Here are some pictures of the difference.

Before
http://home.comcast.net/~polosport8/P1010005.JPG

After
http://home.comcast.net/~polosport8/P1010008.JPG

Pic of the car after
http://home.comcast.net/~polosport8/P1010010.JPG

632 Regal
08-26-2005, 10:18 AM
looks better!

Bellicose Right Winger
08-26-2005, 11:15 AM
Looks good indeed.
Do you have any before and after pics of the springs?
Did you cut one coil as measured from the end?
Did you reform the end of the spring to restore the end configuration that previously existed?

Can you take a measurement, as described in Bentley, from the edge of the wheel nearest the ground vertically to the fender well opening? Should be like 22-23". Need to tell us the wheel diameter so we can compare to factory stock.

Thanks,
Paul Shovestul

Bellicose Right Winger
08-26-2005, 11:18 AM
All you have to do now is mount some LR78-15's and it'll look like Jeff's. :D

Paul Shovestul


looks better!

bullyd
08-26-2005, 03:13 PM
where are you based? as cutting the springs in the uk will make your car fail the mot as a 'cut' spring is classed as a 'broken' spring, i can supply a set of springs that will lower your car 40mm for £75 inc delivery (if in uk), they the same as i used on my e28 and they didnt hurt the ride too bad at all but made the car look the business

93-525i
08-26-2005, 03:54 PM
where are you based? as cutting the springs in the uk will make your car fail the mot as a 'cut' spring is classed as a 'broken' spring, i can supply a set of springs that will lower your car 40mm for £75 inc delivery (if in uk), they the same as i used on my e28 and they didnt hurt the ride too bad at all but made the car look the business

I'm in the US. Portland, Oregon to be exact. We don't have a "MOT" here as you do, all we have to pass is the air quality test (DEQ). I wouldn't think that the MOT would be able to tell that the springs have been cut since the only way to do so would be to pull them out of their seat. Even though the mot is more thorough and anything we have in the US, it's still not going to take your car apart :)

bullyd
08-26-2005, 04:01 PM
I'm in the US. Portland, Oregon to be exact. We don't have a "MOT" here as you do, all we have to pass is the air quality test (DEQ). I wouldn't think that the MOT would be able to tell that the springs have been cut since the only way to do so would be to pull them out of their seat. Even though the mot is more thorough and anything we have in the US, it's still not going to take your car apart :)

believe me they can spot it, when they raise the car off its wheels the shocks are checked for leaking and at the same time they grab the spring from a coil and give it a yank, if there is any movement they take a closer look, anymore than 3/4 of a coil cut and with no weight on the spring it will move cosiderably when pulled!! :p

uscharalph
08-26-2005, 04:04 PM
believe me they can spot it, when they raise the car off its wheels the shocks are checked for leaking and at the same time they grab the spring from a coil and give it a yank, if there is any movement they take a closer look, anymore than 3/4 of a coil cut and with no weight on the spring it will move cosiderably when pulled!! :p
Boy, it must cost the government a fortune to do those inspections, or do you have to pay for it? How often do they inspect your car?

bullyd
08-26-2005, 04:07 PM
Boy, it must cost the government a fortune to do those inspections, or do you have to pay for it? How often do they inspect your car?
WE have to pay! once a year and its around £35-£40 :(

Paul in NZ
08-26-2005, 05:30 PM
twice a year and 35 to 40....

Dash01
08-26-2005, 08:29 PM
This is really interesting:

You (and a guy in Canada who actually have experience cutting the stock springs by one coil) say it works fine, with no apparentl ill effects.

OTOH, lots of others (who presumably have not themselves tried it) say it would not work safely, if at all.

Seems to me, if you cut off only one coil and use a hack saw or other cool cutting (i.e., not a torch) tool that does not affect the temper of the metal, this should work pretty well, and the price is right.

Kalevera
08-27-2005, 12:28 AM
This is really interesting:

You (and a guy in Canada who actually have experience cutting the stock springs by one coil) say it works fine, with no apparentl ill effects.

OTOH, lots of others (who presumably have not themselves tried it) say it would not work safely, if at all.

Seems to me, if you cut off only one coil and use a hack saw or other cool cutting (i.e., not a torch) tool that does not affect the temper of the metal, this should work pretty well, and the price is right.
Just because he cut the springs and put the car back together and it still somehow manages to stay on its own four wheels doesn't make it right or "good", especially after 5 miles of driving it.

*When* the car gets in an accident, how do you think an insurance adjuster is going to consider the cut springs?

Threads such as this seem to me to indicate a lack of expertise in automotive engineering that I can only equate to the typical garbage discussed on roadfly. In fact, there's so much ******** present in this thread that I frankly thought I'd ended up on the aformentioned site instead of .info.

There are two assertions in this mess that are particularly disheartening to me:

1) "handling didn't change". That's ********. I don't care about what you think you can feel in the car, by cutting a coil out of the front springs, much changed about the suspension geometry (both "beneficial" and negative) and alignment...regardless of whether or not the springs in the car are dead. The tragedy of this is, instead of buying a tuned kit, wherein (at least some) R&D determined the specifications of the product for the given application, the cheap path was taken. Now the "tuned" kit that came with the car from the factory is compromised beyond design limits.

2) "no [apparent] ill effects". Once again, I'm beating a dead horse. The stock boge automatic strut, dead/not dead/worn or broken -- any way you take it, is designed to have a specific amount of travel. Same with the spring. Suspension dynamics 101 indicates that the spring does the suspending of the car, while the strut insert acts as a counter force on the spring action. This results in the spring action being a more controlled motion. By cutting the spring, the amount of work performed by a (likely already dead) strut insert increases dramatically, limiting its usable lifespan. This is why tuned kits come with -- yes, you guessed it -- very specific strut inserts, or "recommended" products. The more immediate concern is that by limiting the spring's potential range, there's the possibility that it could jump the perch. I can't think of a more exciting way to save a few bucks by not doing it the correct way the first time than in having to locate and replace the strut housing, in addition to the spring and strut insert that weren't serviced correctly in the first go around.

Do what you want. It's your car, but I can't respect you for these actions.


best, whit

Dash01
08-27-2005, 10:58 AM
Thank you, Whit, your points are well taken and well stated.

I personally have not yet cut the stock springs or fitted aftermarket springs, because I don't yet know enough about either option to make an informed choice. So, your insight and expertise are much appreciated.

Still, a couple of individuals who have cut their stock springs (by one coil) and then reported their results on this forum, both said the car handled reasonably well afterward. Their anecdotes are the sole basis for my post yesterday.

Ideally, somebody could do a scientific before and after comparison of stock, cut-stock, and various aftermarket springs. As of now, when reading the various posts over the past year or two, one gets the impression that some aftermarket spring brands may be better (or worse) than stock or cut-stock.

At least one brand of aftermarket springs seems to have a bad reputation, meaning that particular vendor probably did not do much R & D.

What brand do you recommend for use with stock shocks on a 535i, to lower the car by ~1-1.5" and still retain essentially stock ride and handling?


Just because he cut the springs and put the car back together and it still somehow manages to stay on its own four wheels doesn't make it right or "good", especially after 5 miles of driving it.

*When* the car gets in an accident, how do you think an insurance adjuster is going to consider the cut springs?

Threads such as this seem to me to indicate a lack of expertise in automotive engineering that I can only equate to the typical garbage discussed on roadfly. In fact, there's so much ******** present in this thread that I frankly thought I'd ended up on the aformentioned site instead of .info.

There are two assertions in this mess that are particularly disheartening to me:

1) "handling didn't change". That's ********. I don't care about what you think you can feel in the car, by cutting a coil out of the front springs, much changed about the suspension geometry (both "beneficial" and negative) and alignment...regardless of whether or not the springs in the car are dead. The tragedy of this is, instead of buying a tuned kit, wherein (at least some) R&D determined the specifications of the product for the given application, the cheap path was taken. Now the "tuned" kit that came with the car from the factory is compromised beyond design limits.

2) "no [apparent] ill effects". Once again, I'm beating a dead horse. The stock boge automatic strut, dead/not dead/worn or broken -- any way you take it, is designed to have a specific amount of travel. Same with the spring. Suspension dynamics 101 indicates that the spring does the suspending of the car, while the strut insert acts as a counter force on the spring action. This results in the spring action being a more controlled motion. By cutting the spring, the amount of work performed by a (likely already dead) strut insert increases dramatically, limiting its usable lifespan. This is why tuned kits come with -- yes, you guessed it -- very specific strut inserts, or "recommended" products. The more immediate concern is that by limiting the spring's potential range, there's the possibility that it could jump the perch. I can't think of a more exciting way to save a few bucks by not doing it the correct way the first time than in having to locate and replace the strut housing, in addition to the spring and strut insert that weren't serviced correctly in the first go around.

Do what you want. It's your car, but I can't respect you for these actions.


best, whit

Kalevera
08-27-2005, 02:18 PM
Dash, I did not mean to direct my reply at your post, in particular. Forgive me if I seemed to attack you in it. I was frustrated with what I was reading, in general.

Frankly, there isn't any way to lower the car and not change handling and alignment characteristics (at least, minutely). Of course, ceteris paribus: replacing a dead suspension with ANYTHING is going to yield noticeable improvement, and very few people know how they rode from the factory -- I'm assuming here that the existing suspension on a given car is in excellent working condition.

There's a distinct tradeoff between wheel gap and center of gravity. I find the sachs kit to ride slightly firmer than stock in most driving situations while eliminating most wheel gap. The ride gets progressively firmer in the corners/where it counts. It's not an uncomfortable compromise; one definitely worth making in the case of my car and my wishes. I've never installed a set of vogtland springs, but I think that those with them on their cars will attest to their handling characteristics. But the fallacy of lowering a car and keeping the stock "ride" just doesn't work. And in my book, the compromise that one assumes by cutting a stock spring (again, all other things being equal) isn't a good or responsible decision.

best, whit

JAlfredPrufrock
08-27-2005, 03:19 PM
Voted bad idea.

But what do I know?

632 Regal
08-27-2005, 03:40 PM
I think there was about one coil of preload with the stock front springs, maybe a bit more...soo if there is still some (1/4 coil) preload it shouldnt jump off the perch. I agree whole heartedly with Whit on this but I have in my past...with american steel created "hack" and as a game of chance or just messing around I have done the same with them...also with minimal negetive reactions...but on that same point as I made earlier the end of the coil is slightly flatened to reduce corner load and that cant be accomplished without heating and bending the coil...which will adversly affect the temper and eventually crack...been there done that.

93-525i
08-29-2005, 10:41 AM
Just because he cut the springs and put the car back together and it still somehow manages to stay on its own four wheels doesn't make it right or "good", especially after 5 miles of driving it.

*When* the car gets in an accident, how do you think an insurance adjuster is going to consider the cut springs?

Threads such as this seem to me to indicate a lack of expertise in automotive engineering that I can only equate to the typical garbage discussed on roadfly. In fact, there's so much ******** present in this thread that I frankly thought I'd ended up on the aformentioned site instead of .info.

There are two assertions in this mess that are particularly disheartening to me:

1) "handling didn't change". That's ********. I don't care about what you think you can feel in the car, by cutting a coil out of the front springs, much changed about the suspension geometry (both "beneficial" and negative) and alignment...regardless of whether or not the springs in the car are dead. The tragedy of this is, instead of buying a tuned kit, wherein (at least some) R&D determined the specifications of the product for the given application, the cheap path was taken. Now the "tuned" kit that came with the car from the factory is compromised beyond design limits.

2) "no [apparent] ill effects". Once again, I'm beating a dead horse. The stock boge automatic strut, dead/not dead/worn or broken -- any way you take it, is designed to have a specific amount of travel. Same with the spring. Suspension dynamics 101 indicates that the spring does the suspending of the car, while the strut insert acts as a counter force on the spring action. This results in the spring action being a more controlled motion. By cutting the spring, the amount of work performed by a (likely already dead) strut insert increases dramatically, limiting its usable lifespan. This is why tuned kits come with -- yes, you guessed it -- very specific strut inserts, or "recommended" products. The more immediate concern is that by limiting the spring's potential range, there's the possibility that it could jump the perch. I can't think of a more exciting way to save a few bucks by not doing it the correct way the first time than in having to locate and replace the strut housing, in addition to the spring and strut insert that weren't serviced correctly in the first go around.

Do what you want. It's your car, but I can't respect you for these actions.


best, whit


Wow, this is quite the heated responce. I've gone through many cars, currently have the 525 and an SLK. I've lowered the suspension on every car I've had, and I've done it with aftermarket suspension kits. The 525 is my daily driver and a car I didn't plan to put much money into and I wanted to see how simply cutting a spring would act compared to aftermarket spring options. I've now put about 600 miles over the weekend on the car and it rides great. Now I know that this has changed my suspension characteristics, but they are not changes that are noticeable.

I have gone over some good size potholes and speed bumps and I can tell you that when the spring is decompresses there is to much preassure for it to simply jump the perch. Now if I'm in an accident and the car is hit from the front, the strutt would most likely bend before the spring would come out of the housing. You also have to realize that if the spring were to jump the perch, it will lower that side by about another inch while dislodged, becuase it coils around the struff it's not going to fly out the side or anything.
Here is the bottom line, If you take your car tot he track, invest in a nice aftermarket suspension. If you drive your car as leisure, this has given me a stock like ride and brought the front down a bit as well without the extreme camber changes that aftermarket springs will provide.

J

Dave M
08-29-2005, 11:46 AM
This is really interesting:

You (and a guy in Canada who actually have experience cutting the stock springs by one coil) say it works fine, with no apparentl ill effects.

OTOH, lots of others (who presumably have not themselves tried it) say it would not work safely, if at all.

Seems to me, if you cut off only one coil and use a hack saw or other cool cutting (i.e., not a torch) tool that does not affect the temper of the metal, this should work pretty well, and the price is right.

OK, I'll admit it, I'm the "guy in Canada" who has experience cutting springs on the e34 as well as other vehicles. For those interested, I've included the link to my input when this topic was last up for discussion. It does include photos and a few of my thoughts. And no, the results of the spring cut are not associated with the body damage, but admitadely a humerous combo. For those who don't read it, I will say that it was done as an experiment/temporary 'fix' with full intent to install an eibach pro kit, which was done in due course (very happy wit the result:) ).

This post has gotten a little too heated for my liking, so I'll leave it at that, except to say that all the vehicles I've performed the work on have been driven for many miles, never shown signs of sketchy handling, never structurally failed in any respect, and passed all inspections. There is no noticeable sag or looseness in a cut e34 spring and no chance of it jumping the perches (mayby with a 3mm pad?). As well, once weighted, the bottom cut coil seats nicely in the lower perch.

Many of you, whit especially, have valid points and are stating the appropriate things when speaking to the group. I respect that and hope members take my experience with a big grain of salt.

Dave M

http://www.bimmer.info/forum/showthread.php?p=16813#post16813