
Strut coilover conversion? Any thoughts on how?
-
Steve --
- Forum Admin
- Drives: whatever I can get my hands on
- Location:
- St. Pete
- Joined: November 2006
- Posts: 5122
- First Name: Steve
- Last Name: --
- Favorite Car: whatever I can get my hands on
- Location: St. Pete
Strut coilover conversion? Any thoughts on how?

Steven Frank
Class M3 Miata
Proud disciple of the "Push Harder, Suck Less" School of Autocross
______________
I'll get to it. Eventually...
Class M3 Miata
Proud disciple of the "Push Harder, Suck Less" School of Autocross
______________
I'll get to it. Eventually...
-
Bill L-
- Notorious
- Drives: Golf Sportwagen
- Location:
- Odessa
- Joined: February 2017
- Posts: 572
- First Name: Bill
- Last Name: L-
- Favorite Car: Golf Sportwagen
- Location: Odessa
Strut coilover conversion? Any thoughts on how?
thanks, it was fun writing my own prescription on this one.Loren wrote:Nice work! Being that close to target with so many approximated variables is great!
Now, put some stiffer springs on it.![]()
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.
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.
Critical damping ??? We don't need no stinking critical damping !
-
Steve --
- Forum Admin
- Drives: whatever I can get my hands on
- Location:
- St. Pete
- Joined: November 2006
- Posts: 5122
- First Name: Steve
- Last Name: --
- Favorite Car: whatever I can get my hands on
- Location: St. Pete
Strut coilover conversion? Any thoughts on how?

Steven Frank
Class M3 Miata
Proud disciple of the "Push Harder, Suck Less" School of Autocross
______________
I'll get to it. Eventually...
Class M3 Miata
Proud disciple of the "Push Harder, Suck Less" School of Autocross
______________
I'll get to it. Eventually...
-
Loren Williams
- Forum Admin
- Drives: A Mirage
- Location:
- Safety Harbor
- Joined: December 2006
- Posts: 13044
- First Name: Loren
- Last Name: Williams
- Favorite Car: A Mirage
- Location: Safety Harbor
Strut coilover conversion? Any thoughts on how?
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!
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!
Loren Williams - Loren @ Invisiblesun.org
The "Push Harder, Suck Less" philosophy explained:
Push Harder - Drive as close to the limit of your tires as possible.
Suck Less - Drive something resembling a proper racing line.
The "Push Harder, Suck Less" philosophy explained:
Push Harder - Drive as close to the limit of your tires as possible.
Suck Less - Drive something resembling a proper racing line.
-
Dan Estep
- Notorious
- Drives: A different kind of Miata
- Location:
- The driver's seat
- Joined: October 2015
- Posts: 832
- First Name: Dan
- Last Name: Estep
- Favorite Car: A different kind of Miata
- Location: The driver's seat
Strut coilover conversion? Any thoughts on how?
I love that this thread exists... 

-
Bill L-
- Notorious
- Drives: Golf Sportwagen
- Location:
- Odessa
- Joined: February 2017
- Posts: 572
- First Name: Bill
- Last Name: L-
- Favorite Car: Golf Sportwagen
- Location: Odessa
Strut coilover conversion? Any thoughts on how?
thanks!Loren wrote:
Not sure they'd work well with a 2.5" spring, though.
saw these discussed on a Grassroots thread.
there are others for 2.5id from Howe and Longacre, but about double the cost.
Critical damping ??? We don't need no stinking critical damping !
-
Loren Williams
- Forum Admin
- Drives: A Mirage
- Location:
- Safety Harbor
- Joined: December 2006
- Posts: 13044
- First Name: Loren
- Last Name: Williams
- Favorite Car: A Mirage
- Location: Safety Harbor
Strut coilover conversion? Any thoughts on how?
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.
I probably still have a pair of those out in the garage if you want to play with them before you buy.
Loren Williams - Loren @ Invisiblesun.org
The "Push Harder, Suck Less" philosophy explained:
Push Harder - Drive as close to the limit of your tires as possible.
Suck Less - Drive something resembling a proper racing line.
The "Push Harder, Suck Less" philosophy explained:
Push Harder - Drive as close to the limit of your tires as possible.
Suck Less - Drive something resembling a proper racing line.
-
Bill L-
- Notorious
- Drives: Golf Sportwagen
- Location:
- Odessa
- Joined: February 2017
- Posts: 572
- First Name: Bill
- Last Name: L-
- Favorite Car: Golf Sportwagen
- Location: Odessa
Strut coilover conversion? Any thoughts on how?
thank you for that kind offer. I'd try themLoren wrote:
I probably still have a pair of those out in the garage if you want to play with them before you buy.
Critical damping ??? We don't need no stinking critical damping !
-
Loren Williams
- Forum Admin
- Drives: A Mirage
- Location:
- Safety Harbor
- Joined: December 2006
- Posts: 13044
- First Name: Loren
- Last Name: Williams
- Favorite Car: A Mirage
- Location: Safety Harbor
Strut coilover conversion? Any thoughts on how?
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!
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!
Loren Williams - Loren @ Invisiblesun.org
The "Push Harder, Suck Less" philosophy explained:
Push Harder - Drive as close to the limit of your tires as possible.
Suck Less - Drive something resembling a proper racing line.
The "Push Harder, Suck Less" philosophy explained:
Push Harder - Drive as close to the limit of your tires as possible.
Suck Less - Drive something resembling a proper racing line.
-
Bill L-
- Notorious
- Drives: Golf Sportwagen
- Location:
- Odessa
- Joined: February 2017
- Posts: 572
- First Name: Bill
- Last Name: L-
- Favorite Car: Golf Sportwagen
- Location: Odessa
Strut coilover conversion? Any thoughts on how?
cool! next open is fine. After that, I'll check them out fitment wise both front and backLoren 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!
Critical damping ??? We don't need no stinking critical damping !
-
Bill L-
- Notorious
- Drives: Golf Sportwagen
- Location:
- Odessa
- Joined: February 2017
- Posts: 572
- First Name: Bill
- Last Name: L-
- Favorite Car: Golf Sportwagen
- Location: Odessa
Strut coilover conversion? Any thoughts on how?
dang here they aremymomswagon wrote:
real tires are on the way. Steve and I are committed to wearing out those Federals so we can try them out.


Critical damping ??? We don't need no stinking critical damping !
-
Dan -B-
- Well-Known
- Drives: Mazda Free (As Mike Brewer would say)
- Location:
- Palm Harbor
- Joined: October 2014
- Posts: 351
- First Name: Dan
- Last Name: -B-
- Favorite Car: Mazda Free (As Mike Brewer would say)
- Location: Palm Harbor
Strut coilover conversion? Any thoughts on how?
Uh-oh look out for Bill
now there will be two lines of shame to contend with...
The Mirage and the Automatic Wagon

The Mirage and the Automatic Wagon

-
Steve --
- Forum Admin
- Drives: whatever I can get my hands on
- Location:
- St. Pete
- Joined: November 2006
- Posts: 5122
- First Name: Steve
- Last Name: --
- Favorite Car: whatever I can get my hands on
- Location: St. Pete
Strut coilover conversion? Any thoughts on how?
Ah, now, ain't that a purty sight.mymomswagon wrote: dang here they are

Steven Frank
Class M3 Miata
Proud disciple of the "Push Harder, Suck Less" School of Autocross
______________
I'll get to it. Eventually...
Class M3 Miata
Proud disciple of the "Push Harder, Suck Less" School of Autocross
______________
I'll get to it. Eventually...
-
Doug Adams
- Notorious
- Drives: 2004 RX-8
- Location:
- Spring Hill
- Joined: April 2011
- Posts: 4105
- First Name: Doug
- Last Name: Adams
- Favorite Car: 2004 RX-8
- Location: Spring Hill
Strut coilover conversion? Any thoughts on how?
Well that's one way to get new stickers. Go for it.
-
Bill L-
- Notorious
- Drives: Golf Sportwagen
- Location:
- Odessa
- Joined: February 2017
- Posts: 572
- First Name: Bill
- Last Name: L-
- Favorite Car: Golf Sportwagen
- Location: Odessa
Strut coilover conversion? Any thoughts on how?
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.
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.

Critical damping ??? We don't need no stinking critical damping !
-
Loren Williams
- Forum Admin
- Drives: A Mirage
- Location:
- Safety Harbor
- Joined: December 2006
- Posts: 13044
- First Name: Loren
- Last Name: Williams
- Favorite Car: A Mirage
- Location: Safety Harbor
Strut coilover conversion? Any thoughts on how?
Way to play the game, sir!
Loren Williams - Loren @ Invisiblesun.org
The "Push Harder, Suck Less" philosophy explained:
Push Harder - Drive as close to the limit of your tires as possible.
Suck Less - Drive something resembling a proper racing line.
The "Push Harder, Suck Less" philosophy explained:
Push Harder - Drive as close to the limit of your tires as possible.
Suck Less - Drive something resembling a proper racing line.
-
Bill L-
- Notorious
- Drives: Golf Sportwagen
- Location:
- Odessa
- Joined: February 2017
- Posts: 572
- First Name: Bill
- Last Name: L-
- Favorite Car: Golf Sportwagen
- Location: Odessa
Strut coilover conversion? Any thoughts on how?
in small bitesLoren wrote:Way to play the game, sir!

Critical damping ??? We don't need no stinking critical damping !
-
Bill L-
- Notorious
- Drives: Golf Sportwagen
- Location:
- Odessa
- Joined: February 2017
- Posts: 572
- First Name: Bill
- Last Name: L-
- Favorite Car: Golf Sportwagen
- Location: Odessa
Strut coilover conversion? Any thoughts on how?
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.mymomswagon wrote:in small bitesLoren wrote:Way to play the game, sir!but it's fun
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.


Critical damping ??? We don't need no stinking critical damping !
-
Loren Williams
- Forum Admin
- Drives: A Mirage
- Location:
- Safety Harbor
- Joined: December 2006
- Posts: 13044
- First Name: Loren
- Last Name: Williams
- Favorite Car: A Mirage
- Location: Safety Harbor
Strut coilover conversion? Any thoughts on how?
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.
And that's why it doesn't feel harsh. The rubber is making it nice and progressive.
Loren Williams - Loren @ Invisiblesun.org
The "Push Harder, Suck Less" philosophy explained:
Push Harder - Drive as close to the limit of your tires as possible.
Suck Less - Drive something resembling a proper racing line.
The "Push Harder, Suck Less" philosophy explained:
Push Harder - Drive as close to the limit of your tires as possible.
Suck Less - Drive something resembling a proper racing line.
-
Bill L-
- Notorious
- Drives: Golf Sportwagen
- Location:
- Odessa
- Joined: February 2017
- Posts: 572
- First Name: Bill
- Last Name: L-
- Favorite Car: Golf Sportwagen
- Location: Odessa
Strut coilover conversion? Any thoughts on how?
makes sense. they actually are semi compressed, pic shows fronts at full droop, they're thicker than the gaps between the coils.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.
I'm sure they give a little more as the car corners.
Critical damping ??? We don't need no stinking critical damping !
Return to “Autocross/Track Setup”
Who is online
Users browsing this forum: No registered users and 1 guest