EM Coilover grinding on axle
Thread Starter
Pro
Joined: Apr 2014
Posts: 719
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From: Helotes Texas
Hey Tom, front spring was damaged so I figured why not change to coilovers, perhaps in hindsight not the brightest idea I've ever had, But then again buying a $2k C4 7yrs ago and dumping money into ever since was a bad idea as well. Clearly I'm a slow learner and a glutton for punishment
Thread Starter
Pro
Joined: Apr 2014
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From: Helotes Texas
I was typing my long response above when you changed this. Please read what I wrote before you do something with these brackets that prevents you from sending them back for a refund!
Edit: I see that you did. Do that bind test that I mentioned first. If there isn't enough space up top to move it around in the car, bolt it to something solid on a bench and do it out of the car.
Edit: I see that you did. Do that bind test that I mentioned first. If there isn't enough space up top to move it around in the car, bolt it to something solid on a bench and do it out of the car.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Hey Tom, front spring was damaged so I figured why not change to coilovers, perhaps in hindsight not the brightest idea I've ever had, But then again buying a $2k C4 7yrs ago and dumping money into ever since was a bad idea as well. Clearly I'm a slow learner and a glutton for punishment
Thread Starter
Pro
Joined: Apr 2014
Posts: 719
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From: Helotes Texas
Well got my trans issue fixed, so I was able to drive the car and so far no grinding on the axle after returning to the stock bolt and raising the coilovers further up. My alignment is so out of wack unfortunately that I couldn't push it during my test drive to see if I will have any drive line issues. Still waiting on the custom bracket to get here
Max G’s
Joined: Nov 2008
Posts: 2,751
Likes: 79
From: Monroe OH
NCM Sinkhole Donor
Im thinking just as Kevova mentioned, you need to check your torque arms. You may have worn out bushings in your torque arms causing the suspension to move under load which is why it was only rubbing when turning in a particular direction. I don't have any issues with my coilovers touching or rubbing the axle shafts. I do have heim jointed torque rods as well as the rest of the suspension parts are heim jointed so there is no movement in my suspension. Good Luck hope it works out.
Le Mans Master
Joined: Aug 2015
Posts: 6,118
Likes: 1,994
From: St. Charles MO
Im thinking just as Kevova mentioned, you need to check your torque arms. You may have worn out bushings in your torque arms causing the suspension to move under load which is why it was only rubbing when turning in a particular direction. I don't have any issues with my coilovers touching or rubbing the axle shafts. I do have heim jointed torque rods as well as the rest of the suspension parts are heim jointed so there is no movement in my suspension. Good Luck hope it works out.
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
The early car uses a different style of shock and its location if fixed since bracket it welded to frame. Probably why there are few coil over kits for early cars. The later kits can have a slotted bracket to adjust position of upper mount. Bracket uses holes for plate the OEM shock mounts on. Not having heim joints can laterally stress mounting points, because C4 rear suspension isn't linear. It's more radial all components are moving up / down and in/ out as they articulate through their travel.
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Thread Starter
Pro
Joined: Apr 2014
Posts: 719
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From: Helotes Texas
Well I was able to limp to my buddies shop to get my alignment done, and I had zero rubbing on the driveline after it was Aligned and I desperately tried to get it to rub, So it looks like I'm finally getting some luck. The Heim jointed camber arms/SPC upper control arm were a absolute pleasure to work with according to my alignment guy and the car feels entirely different now, I still intend to use the SRG bracket for some added strength on that rear knuckle.
After a spirited 30 min drive I must say the EM coilovers have impressed me, Can't speak on other coilover kits but if you have a limited budget these seem worth it so far despite the headaches that may or may not have been specific to my car (12 owners)
After a spirited 30 min drive I must say the EM coilovers have impressed me, Can't speak on other coilover kits but if you have a limited budget these seem worth it so far despite the headaches that may or may not have been specific to my car (12 owners)
Last edited by L98Justin; May 1, 2020 at 04:57 PM.
Melting Slicks
Joined: Jun 2011
Posts: 2,383
Likes: 385
From: Leland , North Carolina
Well I was able to limp to my buddies shop to get my alignment done, and I had zero rubbing on the driveline after it was Aligned and I desperately tried to get it to rub, So it looks like I'm finally getting some luck. The Heim jointed camber arms/SPC upper control arm were a absolute pleasure to work with according to my alignment guy and the car feels entirely different now, I still intend to use the SRG bracket for some added strength on that rear knuckle.
After a spirited 30 min drive I must say the EM coilovers have impressed me, Can't speak on other coilover kits but if you have a limited budget these seem worth it so far despite the headaches that may or may not have been specific to my car (12 owners)
After a spirited 30 min drive I must say the EM coilovers have impressed me, Can't speak on other coilover kits but if you have a limited budget these seem worth it so far despite the headaches that may or may not have been specific to my car (12 owners)
Le Mans Master
Joined: Aug 2015
Posts: 6,118
Likes: 1,994
From: St. Charles MO
The ride will be different only because the damping and wheel rates from the springs are changed. There is nothing else about a coilover setup that will change the ride. You can change the shocks and get a different-rate leaf spring and make similar changes to ride - it's just hard to get different rates and adjustable ride heights these days because the company that used to make all that stuff (VBP) is out of business.
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Joined: Apr 2014
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From: Helotes Texas
It's certainly much much stiffer, unfortunately I had bad bushings in the stock camber bar, bad intermediate shaft, old and probably bad ball joints and tie rod ends and a cracking front spring. Now it has fresh tie rods/ball joints, heim jointed camber bar, 94 intermediate shaft upgrade plus the coilovers and my custom alignment. It's a entirely different car now, I'm not sure how much of it is due to the coilovers or the replacement of the bad components but I love it
Last edited by L98Justin; May 2, 2020 at 11:30 AM.
Melting Slicks
Joined: Jun 2011
Posts: 2,383
Likes: 385
From: Leland , North Carolina
It's certainly much much stiffer, unfortunately I had bad bushings in the stock camber bar, bad intermediate shaft, old and probably bad ball joints and tie rod ends and a cracking front spring. Now it has fresh tie rods/ball joints, heim jointed camber bar, 94 intermediate shaft upgrade plus the coilovers and my custom alignment. It's a entirely different car now, I'm not sure how much of it is due to the coilovers or the replacement of the bad components but I love it
Thread Starter
Pro
Joined: Apr 2014
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From: Helotes Texas
I don't have a problem with it, I love the stiffer ride car stays planted like never before. The roads in San Antonio aren't horrendous on my side of town at least and I drive this car only during the weekends and for AutoX.
Le Mans Master
Joined: Aug 2015
Posts: 6,118
Likes: 1,994
From: St. Charles MO
If you get coilovers with standard 2.5" coil springs, you run any spring rates you want. If you get them with decent adjustable rebound, you can also set cushy-soft damping rates on the street. IME, dampers actually affect ride quality more than spring rates. That's because damper forces over sharp bumps (where the suspension is compressing quickly) are many times higher than spring rates. Springs aren't sensitive to the speed of suspension movement, they are only sensitive to displacement (position); and even then, their rate doesn't change with position unless they are progressive springs. OTOH, dampers are completely insensitive to position, and their rate at any instant is only dependent on suspension speed (actually their piston speed).
Last edited by MatthewMiller; May 2, 2020 at 01:43 PM.
Melting Slicks
Joined: Jun 2011
Posts: 2,383
Likes: 385
From: Leland , North Carolina
Melting Slicks
Joined: Jun 2011
Posts: 2,383
Likes: 385
From: Leland , North Carolina
If you get coilovers with standard 2.5" coil springs, you run any spring rates you want. If you get them with decent adjustable rebound, you can also set cushy-soft damping rates on the street. IME, dampers actually affect ride quality more than spring rates. That's because damper forces over sharp bumps (where the suspension is compressing quickly) are many times higher than spring rates. Springs aren't sensitive to the speed of suspension movement, they are only sensitive to displacement (position); and even then, their rate doesn't change with position unless they are progressive springs. OTOH, dampers are completely insensitive to position, and their rate at any instant is only dependent on suspension speed (actually their piston speed).
Thread Starter
Pro
Joined: Apr 2014
Posts: 719
Likes: 67
From: Helotes Texas
The front for the EM coilovers were a piece of cake took me less than 2hrs, I just cut out my front leaf spring since it was damaged and I widened the towers with a large wrench. The rears were the only place I had issues, and after going back to the stock lower shock bolt and getting my alignment done, those rubbing issues are gone, I just drove with a passenger and did some practice Autox runs with no issues whatsoever.
Just be sure to get the Heim jointed Sway bar end links you'll thank yourself greatly. I spent more money than I should have that I will chalk up to OVER THINKING, but I'm stupid happy with my purchase despite my issues that seem to have been self inflicted. (6" speedway shock bolt I didn't need, disgustingly bad alignment.)
Last edited by L98Justin; May 2, 2020 at 06:45 PM.
Thread Starter
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Joined: Apr 2014
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From: Helotes Texas
Well took it to work today, there is construction near the Hospital I work at so I did hit quite a few bumps in the road, and while they certainly weren't pleasant to hit it didn't seem to jar the car any harder than the stock non-z51 springs and brand new shocks it had before. Highway driving seems unchanged for the most part
Impressions so far after some testing with/against my buddies CAM-C Challenger.
Keep in mind I'm still a novice driver my next event will be my 10th, so I may not be able to articulate exactly how the car is moving compared to most of the guys on here. Car is on Federal RS-Pro's (265/35/18 &/275/35/18) a relatively cheap 200tw tire,
Impressions so far after some testing with/against my buddies CAM-C Challenger.
- The Steering responds to my demands instantly rather than taking it as a suggestion, My autox style has been described as "Aggressive" for what it's worth
- Under steer is virtually gone now at least on the fast "replica" mock track we made yesterday
- body roll feels better, but I should be investing in better sway bars soon
- I was able to get on the power quicker, and it felt better in and out of our "Chicago box" compared to our last event we were able to attend
Keep in mind I'm still a novice driver my next event will be my 10th, so I may not be able to articulate exactly how the car is moving compared to most of the guys on here. Car is on Federal RS-Pro's (265/35/18 &/275/35/18) a relatively cheap 200tw tire,