Ok folks I'm totally stumped on my front c5 suspension mounting when I mounted the lower control arm level the c5 coilover would not mount to the arm because of the twist I've attached some pics of how I tried to remount the lower arm so shock mounts but everything is in a bind I've read all the measurements and angles but if someone could explain thing in plain English for a fat old tech challenged guy it woul really help me
Suspension help
- Thread starter lambo1018
- Start date
Moved to the right forum.
I realize you are following the prescribed construction prints, but am somewhat miffed at the rear-most mounts for the LCA being so high on the frame rail. Should you, perhaps, be mounting those tabs much lower, like on the front?
Is there a bind in moving the control arms with no spring on that shock?
I realize you are following the prescribed construction prints, but am somewhat miffed at the rear-most mounts for the LCA being so high on the frame rail. Should you, perhaps, be mounting those tabs much lower, like on the front?
Is there a bind in moving the control arms with no spring on that shock?
That is the issue. If I mount lower on the rear of the lca the lower shock mounts are uneven and shock will not mount to lca
Hmmm.. well, then, it would appear that the LCA is mounted too far rearward. In looking again at the tie rods as they extend from the rack, that they are angling rearward to the steering arms (very poor for ackerman) and may benefit from moving the LCA forward a bit.
I know that with my RCR, the LCAs needed to be mounted in their full forward position within the factory supplied brackets in order to get anywhere near the needed positive camber.
Literally all suspensions are designed with the LCAs and their mounts “level” to the ground.
Very curious..
Thanks for the reply! The tie rods are level but with the lca loose they have fallen. I was hoping for a quick fix from someone but I will figure it out eventually. I really appreciate this forum and you folks!
I don't know if these pics will provide enough info for you to trouble shoot, but thought they might be helpful. This is the C5 suspension setup I used on my Ferrari 250 GTO recreation utilizing coil overs. As you can see, I elected to use the C5 suspension cradle but I did try to retain the control arm angles used by the factory for C5s when fabricating all the mounts.
I just pulled out the creeper and a digital level to attempt an answer to the LCA mount angle. With the car sitting on a level garage floor as last parked, I got a reading of 2 degrees when placing the level under the two mounting tabs on the C5 cradle. There's likely to be some margin of error but the measuring points used appear by eye to be about the same distance to the bolt centerlines. The rear mounting point is higher than the front so a ball park answer is the LCA is mounted with about 2 degrees upward angle from front to rear. I'm guessing a ball park number is likely good enough as the exact LCA angle will vary some as the alignment adjust cams will change the angle some as they are turned during an alignment.
When I was mocking up the C5 suspension on my GTO chassis about 20 years ago (same progress point as you are at), I found a coworker with a C5 Corvette and talked him into bringing it by my garage and I measured it nine ways to Sunday in an attempt to replicate the factory mounting angles/dimensions. I can't find those measurements now or I'd share them with you.
When I was mocking up the C5 suspension on my GTO chassis about 20 years ago (same progress point as you are at), I found a coworker with a C5 Corvette and talked him into bringing it by my garage and I measured it nine ways to Sunday in an attempt to replicate the factory mounting angles/dimensions. I can't find those measurements now or I'd share them with you.
Don’t know if this will help, but a easy Google search came up with this.
There’s a LOT of information out there
Regards Brian
C5 suspension geometry - CorvetteForum - Chevrolet Corvette Forum Discussion
Autocrossing & Roadracing - C5 suspension geometry - UPDATED 2/22/15 I'm working on modeling the C5 suspension geometry and I'm willing to share some of it. Let me know what you'd like to see. My data isn't 100% accurate yet so this is subject to change... C5 Front @ stock ride height RC height...
www.corvetteforum.com
There’s a LOT of information out there
Regards Brian
Thanks but I can't find them
Devin
Supporter
Alan, I would only move the upper control arm to achieve the approximate desired caster and camber angle (upper to lower pivot/ball joint angle) at desired ride height. The upper coilover mount will be the last position dictated by the position of all the other mounting points. In fact I had to learn this lesson and relocate my upper coil mount (see my build post) to keep my Stance air cups from contacting the inner arm during full suspension movement.
BTW, I found spherical joints and tie bars for the coil overs through internet search’s and ended up purchasing mine through Summit Racing.
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I meant to type “positive caster”.. sorry..
Devin
Supporter
The original fixed shock eyelets that came stock were removable on my coil overs and replaced with the proper sized ball mount and tie bars held in place by the appropriate snap rings and clips (bought separately). The tie bars I bought were slotted also to allow slight variable mounting location and hole spacing. Again, nothing is a “kit” or ready to “bolt-on”. Every hour of work on what I have done usually equates to about 2-4 hours of research, parts sourcing, planning and or ordering supplies to make things work or ready to fabricate and install. It’s hard to get a good pic to show the amount of angle the swivel accommodates, but it would be impossible to achieve all the appropriate clearances and mounting points without them IMO. Both top and bottom eyelets have been replaced…the top with a larger hole size for a bolt type mount instead of a tie bars.
Nicely done Devin.
Regards Brian
Regards Brian
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