'custom' lowering spring?

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twastheglow
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'custom' lowering spring?

Post by twastheglow »

I know the topic of lowering springs has been discussed on here...and I know most people have an incredibly hard time locating springs that allow the ride height to be dropped.

I accidentally came across this while looking for something else.

http://www.iemotorsport.com/bmw/E12-sus ... pring.html

Are these a possibility?
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Post by twastheglow »

*EDIT* I noticed these springs were elluded to in another thread...but since these aren't coilovers, I figured they could be discussed here.
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Post by T.Hanson »

Perhaps the acronym, initials referred to in the other post that make understanding what the cool insiders of everything tech,...impossible,...

Ireland Engineering (I.E.), sounded annoying to deal with.

Having installed both Eibach and Alpina lowering springs, their lowering is limited by the shock piston rod extension length.

When the shock is properly mounted at both ends, the spring has got to be long enough to fit in the upper and lower perches. When the shock is fully extended, with the tire off the ground, the spring can't be loose between the perches to be able to rotate or fall out cattywompus.

That's why the ad wants a spring (length) measurement. It's also why just buying lowering springs isn't the whole trick to lowering your suspension. More than what the springs allow takes getting the shocks modified.

Then maybe the suspension (camber) adjusted.
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Post by twastheglow »

Why must the spring stretch from top to bottom with the strut piston fully extended?

Every set of coilovers I've ever installed had springs that were short enough that they were loose until the car was set down. I don't plan on any Dukes Of Hazard driving. lol

But joking aside, I have Intrax springs now with Bilstein Sports and I would still like an extra ~1"+ drop both front and rear (possibly even 1.5" rear to help eliminate a little rake).
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Post by T.Hanson »

Keep in mind I am more student than instructor. If we are lucky, one of those will read this thread and offer enlightenment.

Twenty five years ago after market companies like Intrax, H&R, Eibach offered lowering springs. They did the math and produced the kits to drop the ride height 1.5" just by installation. Time went by, the springs disappeared.

Today the springs are ebay finds or an exercise in finding a set with the proper tech specs. What used to be in the box labeled e12, e24, but now just the specs.

The front struts (see exploded parts view) allow the shock to be inserted in the tube. The spring is captured by a flair at the bottom and a mount at the top. Both ends use a spring perch rubber to cushion, prevent noise. Both ends have notches for the ends of the spring for fit and limiting rotation.

Just a spring would allow unlimited bouncing. Add the shock, it becomes a system, that engineers designed using the weight of the car, suspension geometry, ride quality vs. stiffness for handling, etc.

If you want a visual education, remove the interior, exhaust and a few other bits to see your lowering springs without the 600 pounds compressing them.

E12 springs don't stretch. They have a relaxed height. If the distance between the perches, holding them in their proper positions, is (too) large enough, it will be possible to unweight the inside shocks to let the springs rotate, mess up the fit of the rubbers or worse.

Because shocks are pistons in cylinders with engineered tech specs for compression, travel, it's not a good idea for garage mechanic mods.

If you know all of the above, I believe the answer you are looking for will come from someone with experience in sending the Bilsteins home for revalving, modifying to lower using your springs.

Personally, I had to ask myself why the hassle to get the car low enough to rip the exhaust off on some stupid street bump, log, dip, what.
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Post by Jelmer »

Intrax still has E12 springs.
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twastheglow
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Post by twastheglow »

Jelmer wrote:Intrax still has E12 springs.
That's what I have now. I'd really like to get roughly another 1" lower in the front and 1.5" in the rear. Needless to say this is all for aesthetics.
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Post by twastheglow »

Also, since starting this thread I see that GC offers Eibach springs in whatever length/rate you request as well. I'd clearly prefer Eibach than some "no-name" brand.
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Post by JodyStevens »

Basically anything over 1.5inch drop from stock height is going to need sport struts. Also I would highly doubt you will find a set of springs that will lower another inch on top of that. You're basically looking at coilovers at this point.
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Post by twastheglow »

I have the Bilstein Sport struts now. That's why I'm looking at getting springs made how I request...
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Post by JodyStevens »

So you're going to get springs made that have a 2.5" drop? Thats a big drop from stock. I don't forsee that working out very well.
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Post by twastheglow »

JodyStevens wrote:So you're going to get springs made that have a 2.5" drop? Thats a big drop from stock. I don't forsee that working out very well.
Can you give some insight as to why?
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Post by JodyStevens »

To ride that low the springs will have to be quite stiff, uncomfortably so, to keep from bottoming out. 2.5 inches is A LOT to drop a car on springs alone.

Another user also mentioned that the spring provides a level of tension between the strut housing and the top mount. I would be surprised if a 2.5" lowering spring could provide the necessary force. You would probably be in danger of the spring inproperly seating over bumps etc.

Shortening the strut housing and using shortned struts you could get by this.
David in Seattle
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Post by David in Seattle »

I have B&G springs on my E12. It's just low enough. It rides really well, even with Bilstein sports. It's not a stiff harsh ride at all, even with 16" wheels.

And, if a spring is made in the USA, regardless of brand, it is probably made by Eibach. In fact, Ireland's are made by Eibach.

And Ireland Engineering isn't hard to deal with at all. I order from them all the time. Just don't talk to Jeff Ireland when you call. Ask for Jeremy or Andrew.
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Post by JodyStevens »

David in Seattle wrote:I have B&G springs on my E12. It's just low enough. It rides really well, even with Bilstein sports. It's not a stiff harsh ride at all, even with 16" wheels.

And, if a spring is made in the USA, regardless of brand, it is probably made by Eibach. In fact, Ireland's are made by Eibach.

And Ireland Engineering isn't hard to deal with at all. I order from them all the time. Just don't talk to Jeff Ireland when you call. Ask for Jeremy or Andrew.
B&G springs only lower 1.6"F and 1.2"R. He wants to go down another inch on that. A 1.6" drop wouldnt be too bad but to go another inch it would have to be pretty stiff to not hit the stops constantly.

Ireland isn't bad to deal with. Dealt with them multiple times. Jeff has a hard time responding to emails though.
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