Hi folks, just setting up the front suspension mounting points on my Mk1 using C5 corvette suspension, Can anyone tell me the angle of drop from the chassis to the knuckle on the upper and lower control arms, I already have the camber, caster & angle for the anti dive but cat find anything on the droop angle so that I can set the height of the mounting points. any info would be appreciated
C5 corvette front suspension
- Thread starter LanceC
- Start date
Chris Kouba
Supporter
Hi Lance,
Is this for a scratch build or do you have a chassis already?
Full disclosure, I am not an expert on this but have been pondering things of this nature. From what I've gathered, the classic answer would be to start with the lower ball joint leveled up with its inboard pivots. Have you tried that? What does that look like for you? Note that the arm itself may not appear level due to its geometry, it's only the pivot locations which matter. If the pivots and the ball joint are even, the kinematics don't care about the shape of the arm. A slight droop (inboard pivots higher than the ball joint) might have some camber gain benefits for you. There are many other things to consider as well- roll center, instant center, etc... which will all serve to adjust the hardpoints.
If you have a chassis already, with the lower set level(-ish), that would dictate the angle of the upper for you based on where the mounts are fabbed to the chassis.
If you're building from scratch, you'll likely want the upper ball joint slightly higher than its inboard pivots. How much is slightly? Many things to consider.
If you're not too familiar with designing a suspension, this guy has a series of videos in which he goes through building a GT40. He's pretty tolerable and I thought he did a decent job walking through his process- https://www.youtube.com/results?search_query=ben+beames. Beyond that, you can easily get lost on the internet rabbit hole of suspension set up. The trick is to enjoy the learning process.
Chris
Is this for a scratch build or do you have a chassis already?
Full disclosure, I am not an expert on this but have been pondering things of this nature. From what I've gathered, the classic answer would be to start with the lower ball joint leveled up with its inboard pivots. Have you tried that? What does that look like for you? Note that the arm itself may not appear level due to its geometry, it's only the pivot locations which matter. If the pivots and the ball joint are even, the kinematics don't care about the shape of the arm. A slight droop (inboard pivots higher than the ball joint) might have some camber gain benefits for you. There are many other things to consider as well- roll center, instant center, etc... which will all serve to adjust the hardpoints.
If you have a chassis already, with the lower set level(-ish), that would dictate the angle of the upper for you based on where the mounts are fabbed to the chassis.
If you're building from scratch, you'll likely want the upper ball joint slightly higher than its inboard pivots. How much is slightly? Many things to consider.
If you're not too familiar with designing a suspension, this guy has a series of videos in which he goes through building a GT40. He's pretty tolerable and I thought he did a decent job walking through his process- https://www.youtube.com/results?search_query=ben+beames. Beyond that, you can easily get lost on the internet rabbit hole of suspension set up. The trick is to enjoy the learning process.
Chris
Chris Kouba
Supporter
Sounds like a fun project. Hopefully some of the more knowledgeable members will chime in here as well.
Seeing the arms, it is the upper where the ball joint is in the spindle so it might look flat but be at an angle. The lower looks pretty planar between the inner pivots and ball joint center.
Seeing the arms, it is the upper where the ball joint is in the spindle so it might look flat but be at an angle. The lower looks pretty planar between the inner pivots and ball joint center.
Chris Kouba
Supporter
If that's nominal ride height, I think you'll want the inner pivot below the outer for the upper arm. The first image makes it look like it's drooping at the outboard end. As is, you'll be gaining positive camber as the suspension compresses.
You can use free suspension analyzer to get the points and dimensions. For mine I went with zero anti dive. It’s makes the fab easier and with the low CG of these cars and mid engine configuration I felt the benefits were negligible. Just do a good google search, the dimensions are all over the internet.
