Solution to rough ride on lowered C3s
#1
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Location: Hudson OH
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Solution to rough ride on lowered C3s
This seasons I went ahead and accomplished a few items
1) Solid mounted the x member which raised the diff ~ 3/4"
2) Installed VBP dual mount spring
3) Installed smart struts
4) Installed QA1 single adjustable shocks
What I found is the ride to be somewhat rough/bouncy no matter what setting I had the shocks on. An email over to QA1 indicated that anything less than 12.5" center to center starts to get into high damping rates which reduces the difference between settings and makes for a rough ride.
I measured mine at 11"...10.5" is end of travel! GM was not doing us any favors in how they mounted the shocks. I saw one solution where the individual pocketed the frame and moved the shock mount up an inch.
I went the other way and remanufactured the lower shock mount. This modification is reversible and more easily made by your average DIYer. Here is what you need:
Tools:
1) welder
2) Drill/bits
3) Jig saw
4) Grinder
Materials
1) 1/4" steel plate
2) 5/8 fine thread grade 8 bolts
3) Whatever size bolts needed for your shocks. QA1 was also 5/8"
Don't forget to put a flat on one side of the bolt so it slips through the knuckle. Though you cannot see it, there is another ear on the outer side of the shock for the thru bolt. I also trimmed the bump stops about 1" to compensate for moving the x member higher.
With the increased shock travel the ride is greatly improved. I have the spring on the 3rd hole and the shocks set at 7. I believe 3-7 will give a good ride on most roads.
1) Solid mounted the x member which raised the diff ~ 3/4"
2) Installed VBP dual mount spring
3) Installed smart struts
4) Installed QA1 single adjustable shocks
What I found is the ride to be somewhat rough/bouncy no matter what setting I had the shocks on. An email over to QA1 indicated that anything less than 12.5" center to center starts to get into high damping rates which reduces the difference between settings and makes for a rough ride.
I measured mine at 11"...10.5" is end of travel! GM was not doing us any favors in how they mounted the shocks. I saw one solution where the individual pocketed the frame and moved the shock mount up an inch.
I went the other way and remanufactured the lower shock mount. This modification is reversible and more easily made by your average DIYer. Here is what you need:
Tools:
1) welder
2) Drill/bits
3) Jig saw
4) Grinder
Materials
1) 1/4" steel plate
2) 5/8 fine thread grade 8 bolts
3) Whatever size bolts needed for your shocks. QA1 was also 5/8"
Don't forget to put a flat on one side of the bolt so it slips through the knuckle. Though you cannot see it, there is another ear on the outer side of the shock for the thru bolt. I also trimmed the bump stops about 1" to compensate for moving the x member higher.
With the increased shock travel the ride is greatly improved. I have the spring on the 3rd hole and the shocks set at 7. I believe 3-7 will give a good ride on most roads.
Last edited by cbrock; 09-01-2016 at 09:53 AM.
#4
Smart solution! How's the ride height now?
#5
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I'll have to measure the ground to fender distance. In General I was shooting for 2 finger gap all the way around. I have room to move lower now but with SE MI roads, it's about where it has to be.
With the steel spring that was in it the car looked like a 4x4
With the steel spring that was in it the car looked like a 4x4
#6
Le Mans Master
Never have anything lower than the rim, ever! That's an extremely dangerous thing. I've seen what will happen if you have a flat tire and it isn't pretty. You would not be able to control the car. Seriously re think it.
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midigike (09-02-2016)
#8
Drifting
He was shocked and never heard of such a thing. I told him when he goes in gear the rear will drop, and during hard acceleration too.
I'm curious because I have the VBP 340lb mono rear and coilover front suspension and my ride is very compliant and not bouncy.
#9
Le Mans Master
In the event of a bolt it would probably bend or shear off ,but something with some structural substance would be a different matter.
I knew a guy years ago with a falcon sprint with traction bars that hung below the rim,everybody warned him about it. Driving like a nut in an area being repaired with the sewer covers raised he hit one shot his car off the road onto a sidewalk across the median. Killed a 7 or 8 year old kid on his bicycle. If there was an upside to it that clown lost his drivers licence forever.after doing some jail time.
I knew a guy years ago with a falcon sprint with traction bars that hung below the rim,everybody warned him about it. Driving like a nut in an area being repaired with the sewer covers raised he hit one shot his car off the road onto a sidewalk across the median. Killed a 7 or 8 year old kid on his bicycle. If there was an upside to it that clown lost his drivers licence forever.after doing some jail time.
Last edited by 7t9l82; 09-02-2016 at 08:27 AM.
#11
Drifting
Member Since: Aug 2015
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C3 of Year Finalist (track prepared) 2019
I'm pretty sure the angle of the pic makes it look worse than it is, and that with 17"+ wheels which he says he is fitting that it will be fine. Nice job, thanks for sharing!
#12
Had a 1976 L-82, 4-sp
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Royal Canadian Navy
I was just at a show and one of the guys had a real bad 80 with flares, monster 315 meats in the back and we got to discussing ride height. He felt he was still higher in back than he wanted. I looked underneath and he had 10 inch bolts that were way below rim level. I told him if he ever gets a flat to watch he doesn't dig that bolt in the ground and rip the rear right out of it!
He was shocked and never heard of such a thing. I told him when he goes in gear the rear will drop, and during hard acceleration too.
I'm curious because I have the VBP 340lb mono rear and coilover front suspension and my ride is very compliant and not bouncy.
He was shocked and never heard of such a thing. I told him when he goes in gear the rear will drop, and during hard acceleration too.
I'm curious because I have the VBP 340lb mono rear and coilover front suspension and my ride is very compliant and not bouncy.
Last edited by resdoggie; 09-03-2016 at 09:58 PM.