Awesome video again! I'll be referencing this as I look at modernizing my 49 Cadillac. Thanks for the tip on the free software and how to use it. This will seriously help me get a rough draft of an idea on the plan rather than weld and rebuild method.
Great explanation. From doing fsae in engineering another good book to read is Race Car Vehicle Dynamics by Milliken has some good estimates and guides for designs. One thing I will say about the book you can get lost fairly easily. But you can go a bit further and work out requirements for ARB stiffness if you don't want a crazy high spring rate for better mechanical grip from your tires etc.
Great video. I felt I had a good understanding of this before but this connected some more dots. Now I think I understand why the RC is almost always a few inches below the CG on steet cars. If the RC was only an inch below the CG, the dynamic changes in the suspension might cause the RC to go above the CG, which would result in weight jacking. By keeping the RC a little bit lower, you avoid that risk. A compromise. Is that correct?
Maybe somebody with more industry knowledge can give a better answer than me. I stay away from guessing what road manufacturers are doing because sometimes they have genius reasons for doing something that on the face of it (with only a basic understanding) seems wrong (like using bump steer to give a car a certain amount of "feel"... I still want to know more about that one). But I can say that weight jacking happens to some degree anytime the roll center isn't at ground level, regardless of the CG. But even that is beyond what I use Roll Centers for. For me it boils down to High Roll Center = faster load transition, less spring/shock roll resistance needed, but poorer grip. Low Roll Center = slower load transition, more spring/shock roll resistance needed, higher grip. And you can tune the front and rear handling by the relation between the two. Beyond that and I start getting conflicting information that often has little application. So I just get on with it. But I did a search on roll centers last night and I'm finding a lot more information than the last time I searched for it. So the answer may be out there for you. I'm thinking I probably didn't need to make this video after all. Others have probably done it better.
Outstanding stuff, thank you for the upload!!
This is very helpful, thanks!
This tutorial is fantastic!!! I’ve never heard RC explained so plainly that I now finally get IT. Thank you 🙏
Awesome video again! I'll be referencing this as I look at modernizing my 49 Cadillac. Thanks for the tip on the free software and how to use it. This will seriously help me get a rough draft of an idea on the plan rather than weld and rebuild method.
loved this! I never quite found clear indications on where the RC are located on road cars vs race cars...
Excellent presentation. A great introduction to understanding roll centres or roll centers.
I love your videos and content. I have a 1963 audi f11 I've converted to rwd. And i incorporated all the things i learn in my chassis modifications
Loving these videos!
Great explanation. From doing fsae in engineering another good book to read is Race Car Vehicle Dynamics by Milliken has some good estimates and guides for designs. One thing I will say about the book you can get lost fairly easily. But you can go a bit further and work out requirements for ARB stiffness if you don't want a crazy high spring rate for better mechanical grip from your tires etc.
Why not use thicker roll bars rather than harder springs to control roll on high cg cars? Thanks.
Great video. I felt I had a good understanding of this before but this connected some more dots. Now I think I understand why the RC is almost always a few inches below the CG on steet cars. If the RC was only an inch below the CG, the dynamic changes in the suspension might cause the RC to go above the CG, which would result in weight jacking. By keeping the RC a little bit lower, you avoid that risk. A compromise. Is that correct?
Maybe somebody with more industry knowledge can give a better answer than me. I stay away from guessing what road manufacturers are doing because sometimes they have genius reasons for doing something that on the face of it (with only a basic understanding) seems wrong (like using bump steer to give a car a certain amount of "feel"... I still want to know more about that one). But I can say that weight jacking happens to some degree anytime the roll center isn't at ground level, regardless of the CG. But even that is beyond what I use Roll Centers for. For me it boils down to High Roll Center = faster load transition, less spring/shock roll resistance needed, but poorer grip. Low Roll Center = slower load transition, more spring/shock roll resistance needed, higher grip. And you can tune the front and rear handling by the relation between the two. Beyond that and I start getting conflicting information that often has little application. So I just get on with it. But I did a search on roll centers last night and I'm finding a lot more information than the last time I searched for it. So the answer may be out there for you. I'm thinking I probably didn't need to make this video after all. Others have probably done it better.
What a great video. Thank you so much for taking the time to produce and post.
Should the roll center for the rear suspension be the same, higher or lower compared to the front roll center?