Strut coilover conversion? Any thoughts on how?

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Strut coilover conversion? Any thoughts on how?

Postby Native » Wed Feb 28, 2018 6:31 pm

:whip:
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Strut coilover conversion? Any thoughts on how?

Postby mymomswagon » Wed Feb 28, 2018 8:41 pm

Loren wrote:Nice work! Being that close to target with so many approximated variables is great!

Now, put some stiffer springs on it. 8-)

A little more spring rate would get you a little more height. And 150# seems absurdly soft for an "upgrade", especially for such a heavy car.

Remember, if you've got the rear suspension to where it's lifting a tire, as soon as that happens, ALL roll resistance goes to the front. You need a pretty significant front spring rate to ease that transition.

Go with a 1" shorter spring and something like a 200# rate... even that isn't very stiff. But, would be an improvement and put your ride height a little closer.
thanks, it was fun writing my own prescription on this one.

yeah that spring rate is nothing to get excited about. played it safe given I was still working with factory struts made to accommodate 140# oe springs. good ride quality for every day though.

for more spring rate at events, might play with packing the front bump stops or isolating a coil with a spring rubber. think it would add some and still be reversible.

real tires are on the way. Steve and I are committed to wearing out those Federals so we can try them out.
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Strut coilover conversion? Any thoughts on how?

Postby Native » Wed Feb 28, 2018 8:49 pm

:notworthy:
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Strut coilover conversion? Any thoughts on how?

Postby Loren » Wed Feb 28, 2018 8:52 pm

You raised the spring rate by... 7%?

Oh, Bill. You're so conservative!

But, I get it. And, yes, coming up with something to stuff into the spring to remove a coil will definitely stiffen it. You can even calculate how much!

I've used these before:
https://www.amazon.com/dp/B000BWCFIM/

Not sure they'd work well with a 2.5" spring, though.

My first custom spring experiment was on my wife's 1996 Saturn when I replaced the shocks. My mission was to improve the car without her noticing! So, I cut 1/2 coil off of each spring, and stuffed in a set of those rubber spacers to remove another active coil. Net result was the car was 3/4" lower and 20% stiffer. And she didn't notice. I attributed it all to "fresh shocks" and told her about it a few weeks later!
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Strut coilover conversion? Any thoughts on how?

Postby ImpostorDan » Wed Feb 28, 2018 9:04 pm

I love that this thread exists... :lol:
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Strut coilover conversion? Any thoughts on how?

Postby mymomswagon » Thu Mar 01, 2018 5:45 am


Loren wrote:
Not sure they'd work well with a 2.5" spring, though.
thanks!

saw these discussed on a Grassroots thread.

there are others for 2.5id from Howe and Longacre, but about double the cost.
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Strut coilover conversion? Any thoughts on how?

Postby Loren » Thu Mar 01, 2018 8:40 am

You could trim the ends and they would conform to the 2.5" diameter. But, you'd probably have to zip-tie them to the spring or something to keep them in place. As long as you're not coil-binding the spring, that could work.

I probably still have a pair of those out in the garage if you want to play with them before you buy.
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Strut coilover conversion? Any thoughts on how?

Postby mymomswagon » Thu Mar 01, 2018 9:18 am


Loren wrote:
I probably still have a pair of those out in the garage if you want to play with them before you buy.
thank you for that kind offer. I'd try them
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Strut coilover conversion? Any thoughts on how?

Postby Loren » Thu Mar 01, 2018 1:49 pm

Found them. I'll throw them in the car for the next event unless you want to come get them sooner.

They are suffering the fate of 20-year-old rubber. Very hard and starting to crumble around the edges. Not sure I'd trust them to last very long, especially in competition. But, they should be good for a test fit. Given their condition, I'm never going to use them, so you can keep them. Trim them to fit your application. Have fun!
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Strut coilover conversion? Any thoughts on how?

Postby mymomswagon » Thu Mar 01, 2018 5:05 pm

Loren wrote:Found them. I'll throw them in the car for the next event unless you want to come get them sooner.

They are suffering the fate of 20-year-old rubber. Very hard and starting to crumble around the edges. Not sure I'd trust them to last very long, especially in competition. But, they should be good for a test fit. Given their condition, I'm never going to use them, so you can keep them. Trim them to fit your application. Have fun!
cool! next open is fine. After that, I'll check them out fitment wise both front and back
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Strut coilover conversion? Any thoughts on how?

Postby mymomswagon » Sat Mar 03, 2018 5:07 pm


mymomswagon wrote:
real tires are on the way. Steve and I are committed to wearing out those Federals so we can try them out.
dang here they are :)
Image
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Strut coilover conversion? Any thoughts on how?

Postby dbeng » Sat Mar 03, 2018 5:58 pm

Uh-oh look out for Bill :whip: now there will be two lines of shame to contend with...
The Mirage and the Automatic Wagon :geek:
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Strut coilover conversion? Any thoughts on how?

Postby Native » Sat Mar 03, 2018 7:31 pm

mymomswagon wrote: dang here they are
Ah, now, ain't that a purty sight. :lust:
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Strut coilover conversion? Any thoughts on how?

Postby twistedwankel » Sat Mar 03, 2018 9:32 pm

Well that's one way to get new stickers. Go for it.
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Strut coilover conversion? Any thoughts on how?

Postby mymomswagon » Wed Mar 21, 2018 2:59 pm

Had a chance to try out Loren's spring rubbers.

Unfortunately, the diameter was a no-go on the 2.5 id barrels. They were also too tall to squeeze into my rears at full droop....well, I didn't start unbolting anything, so maybe there's a way.

Did some searching for the front on the interweb and found some reasonably priced ($15) spring rubbers for 2.5 id at Speedway.

I called Speedway to get more info before buying. I was asked "what model of car" and was transferred to a very sceptical tech in the circle track department, who wasn't accustomed to VW circle track racers. So I told him that I thought circle track was pretty cool and that I already tried bump springs for autocross, and he warmed right up!

Got my questions answered, product delivered.

Drilled three holes in them, threaded zip ties, lifted car, and fastened them in. Maybe 5 mins per side of work to install or remove.

Springs are 150 lbs and for argument sake, 4 free coils. Isolating a coil, at least by the formula leaves 3 coils and a rate of 200 lbs...but the coils are not equal diameter and there is some deflection, so I just guess we're somewhere between 175 and 200 lbs.

No complaints about DD comfort. No
sign that my struts are under-damped. On the street, might be gripping better..hard to say. Next FAST open will hopefully tell more.

pic shows spring and rubber, at droop. under load it is tightly squeezed with minimal effect on ride height.Image
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Strut coilover conversion? Any thoughts on how?

Postby Loren » Wed Mar 21, 2018 3:12 pm

Way to play the game, sir!
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Strut coilover conversion? Any thoughts on how?

Postby mymomswagon » Wed Mar 21, 2018 3:16 pm

Loren wrote:Way to play the game, sir!
in small bites :) but it's fun
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Strut coilover conversion? Any thoughts on how?

Postby mymomswagon » Tue Apr 03, 2018 2:50 pm

mymomswagon wrote:
Loren wrote:Way to play the game, sir!
in small bites :) but it's fun
since it's so much fun, I decided to add a second rubber on each front side. First rubber was 3/4" tall, new rubber is an inch tall.

On the street, 2nd rubber had the desired effect, causing less roll and the car felt faster in corner exit. No real issue with harshness on stock struts, quite comfortable...firmness mitigated as ride height appears to have increased by about 3/8".

"Theoretical spring rate" is now capped around 300 ?? but I suspect deflection makes it lower. Still, this is encouraging for me as I think I can now swap into much firmer springs without killing the ride or overwhelming the struts .

On an empty backroad, car felt a bit less playful in a few lane change / slalom maneuvers. This motivated me to revisit Loren's loaners for the rear, which I was able to fit with some persistence. They're a little big and overlap but could cut to fit. One set seems to liven the back up again.

ImageImage
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Strut coilover conversion? Any thoughts on how?

Postby Loren » Tue Apr 03, 2018 5:51 pm

What you've created is a sort of progressive spring. As your spring rubbers contact and start to compress, your spring rate increases. At some point, the rubbers are compressed about as much as they're going to, and that's where you'll have your calculated 300# rate.

And that's why it doesn't feel harsh. The rubber is making it nice and progressive.
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Strut coilover conversion? Any thoughts on how?

Postby mymomswagon » Tue Apr 03, 2018 7:11 pm

Loren wrote:What you've created is a sort of progressive spring. As your spring rubbers contact and start to compress, your spring rate increases. At some point, the rubbers are compressed about as much as they're going to, and that's where you'll have your calculated 300# rate.

And that's why it doesn't feel harsh. The rubber is making it nice and progressive.
makes sense. they actually are semi compressed, pic shows fronts at full droop, they're thicker than the gaps between the coils.

I'm sure they give a little more as the car corners.


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