C4 coilover suspension
#21
Melting Slicks
#22
Tech Contributor
The only time I would do them is if I ever feel like I need moar low
#23
Burning Brakes
I plan to do some autocross next year, but mostly I'm going to drive the wheels off the car. I'm not a big fan of the leaf springs and installing coil overs will help out the ride quality. These days coil overs aren't that pricey as they used to be, I thought it was similarly priced upgrade vs buying one those over priced stock C4 Z51 suspension mono leaf spring kits.
#25
The following users liked this post:
Dutch84 (09-01-2020)
#27
#29
Melting Slicks
While I really like my coilovers there is one big thing to consider, if a shock or shock mount breaks, you are not going anywhere. The car will drop down on the corner that broke and you will be on a roll back to get it home. While this is a rare occurance, it could happen. That being said, my car has been through 11 states with one broken mount.
A few years ago the shaft on one of my koni coilover's broke just below the thread of the top mount, i fitted coilover's before there were kits for C4's available.
Lucky the spring kept in place preventing the front of the car hitting the bitumen, i got to drive the car home carefully. (have a modified top mount similar to ""rklessdriver"") and 1/4 inch steel reinforcement on the lower control arm shock mounting plate.
An obvious design flaw at the end of the thread no radius to transfer the load, replaced the coilover shock and been fine since.
I have been running coilovers for close to 20 years, my next ones will be the QA1 with thick 5/8 piston shaft for durability.
Last edited by gerardvg; 09-28-2017 at 07:31 AM.
#30
Melting Slicks
I suppose welding the mount may have weakened the knuckle, i track my c4 as often as i can but that is nothing like public roads and potholes, i will have a look at my rear knuckle to coilover mount. I have gone over many potholes that could swallow a volkswagon whole without incident at quite high speed. I have a mounting bracket and additional support rods that bolted on the the original shock absorber and knuckle, to mount the coilover out further for coilover spring clearance.
Thanks for sharing your misfortune, is a chance others to check their suspension for cracks,
Will have to look if any further strengthening can be done
#31
Le Mans Master
I had the very same thing happen to me, I built my own bottom mount and I know it will not break. I will get a couple pics and post them later. Illinois roads are so bad that I really have no idea how the break got it's start. There were 5 of us, all in Corvettes on a short road trip, I got about 30 miles from home when all of a sudden I heard a loud bang and the rear dropped down, the bottom of the shock was dragging the pavement. I moved it as easily as I could into a parking lot and called a flatbed.
#32
Le Mans Master
Yes but that can happen with the composite spring, they do break while the front will almost drop to the ground the rear has bump stops to get you home.
A few years ago the shaft on one of my koni coilover's broke just below the thread of the top mount, i fitted coilover's before there were kits for C4's available.
Lucky the spring kept in place preventing the front of the car hitting the bitumen, i got to drive the car home carefully. (have a modified top mount similar to ""rklessdriver"") and 1/4 inch steel reinforcement on the lower control arm shock mounting plate.
An obvious design flaw at the end of the thread no radius to transfer the load, replaced the coilover shock and been fine since.
I have been running coilovers for close to 20 years, my next ones will be the QA1 with thick 5/8 piston shaft for durability.
A few years ago the shaft on one of my koni coilover's broke just below the thread of the top mount, i fitted coilover's before there were kits for C4's available.
Lucky the spring kept in place preventing the front of the car hitting the bitumen, i got to drive the car home carefully. (have a modified top mount similar to ""rklessdriver"") and 1/4 inch steel reinforcement on the lower control arm shock mounting plate.
An obvious design flaw at the end of the thread no radius to transfer the load, replaced the coilover shock and been fine since.
I have been running coilovers for close to 20 years, my next ones will be the QA1 with thick 5/8 piston shaft for durability.
#33
Burning Brakes
Any body make a bracket so you can use the rear lower control "arm" bolt as well as use the original shock bolt? It should be a lot more beefier.
For the lower coil over bolt, instead of just using only shock bolt. Just an idea. That's the way I was gonna build mine.
For the lower coil over bolt, instead of just using only shock bolt. Just an idea. That's the way I was gonna build mine.
#34
Le Mans Master
Here are the ones I made up, the 3 red arrows show where the mount bolts to the knuckle and then the mount is made with two pieces of 1/4 inch flat stock, (as is the rest of the mount) this makes double shear strength which should be impossible to break, (I hope)
Last edited by Midnight 85; 09-28-2017 at 05:21 PM.
The following 2 users liked this post by Midnight 85:
Dutch84 (09-01-2020),
Mike Holmen (09-30-2017)
#35
Burning Brakes
Midnight 85, hate to ask, but do you have the specs on the coilovers? and spring rates? I took a quick look at the rear yesterday, they shock looks shorter than whats on the front.
I see that your using the bearing mounting coilovers. I was leaning toward using the bear mounts coil overs. They seem to be more rigid of a mount that the poly mount.
Looks good buddy. I was also thinking about doing my lower mount similar to yours.
I see that your using the bearing mounting coilovers. I was leaning toward using the bear mounts coil overs. They seem to be more rigid of a mount that the poly mount.
Looks good buddy. I was also thinking about doing my lower mount similar to yours.
#36
Le Mans Master
Midnight 85, hate to ask, but do you have the specs on the coilovers? and spring rates? I took a quick look at the rear yesterday, they shock looks shorter than whats on the front.
I see that your using the bearing mounting coilovers. I was leaning toward using the bear mounts coil overs. They seem to be more rigid of a mount that the poly mount.
Looks good buddy. I was also thinking about doing my lower mount similar to yours.
I see that your using the bearing mounting coilovers. I was leaning toward using the bear mounts coil overs. They seem to be more rigid of a mount that the poly mount.
Looks good buddy. I was also thinking about doing my lower mount similar to yours.
the mount i made is not my idea, i saw the same thing on another c4 group and was impressed with the strength. the downside is that you have to cut the original mount off the knuckle, the upside,, for me anyway,, is that it made my previously broken knuckle usable again. if i can be of any further assistance just ask.
The following users liked this post:
Mike Holmen (09-30-2017)