Caster Angle Increase

AssBurns

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While talking to @Tyler James Inc and @eimkeith today, we were briefly discussing caster angle change throughout suspension cycle, and the benefit of having built in change in caster angle.
As you can see based on this photo from Solo Motorsports XLT kit using the stock upper and lower control arm pivot points, the castor angle increases at bump and is almost 0* at full droop. I drew some shitty lines to reflect the changes as the suspension cycles. The red lines are the paths of the "Ball Joints" and the green line is the caster angle at bump.
I've been thinking about this all day and can't come up with a great reason to purposely have less caster at droop than at bump. I'd think it would be better to have little to no change throughout suspension cycle. Or even have some increased caster angle at droop rather than decreased, so that you keep a positive caster during a front end dive.

Thoughts?

XLT-Series-Tacoma-4Runner-Xtreme-Long-Travel-Front-Suspension-Kit-1.jpg
Image-1.jpg
 

madtaco461

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The reason this exist is because the manufacture has calculated antidive for the stock suspension. Suspension binds up instead of making your shocks do all the work. They can run smaller shocks and get the road handling they designed.

Most kits you see for a tacoma are bolt on. Still uses factory geometry just extended. Now racing you have a lot of shock power we can eliminate antidive. Basically you flatten out your uca in the pic above. What’s the advantage? Well getting rid of antidive you pull stress away from your suspension joints and direct that energy to your shocks.

Handling on dirt between the 2 styles is where I lack knowledge.
 

AssBurns

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The reason this exist is because the manufacture has calculated antidive for the stock suspension. Suspension binds up instead of making your shocks do all the work. They can run smaller shocks and get the road handling they designed.

Most kits you see for a tacoma are bolt on. Still uses factory geometry just extended. Now racing you have a lot of shock power we can eliminate antidive. Basically you flatten out your uca in the pic above. What’s the advantage? Well getting rid of antidive you pull stress away from your suspension joints and direct that energy to your shocks.

Handling on dirt between the 2 styles is where I lack knowledge.
Okay I've been doing some reading on IFS anti-dive, and fuck there is a ton of information and info that goes into IFS suspension geometry compared to solid axle. With IFS, there is a ton of consideration for Thrust based and Torque Based anti-dive and/or pro-dive. It's back to learning more about all this stuff. I thought solid axle suspension design was in depth, but shit this stuff is a whole new dimension.
You basically just gave me an extremely simplified version of what I've been reading about this past hour. Thanks!
 

madtaco461

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Okay I've been doing some reading on IFS anti-dive, and fuck there is a ton of information and info that goes into IFS suspension geometry compared to solid axle. With IFS, there is a ton of consideration for Thrust based and Torque Based anti-dive and/or pro-dive. It's back to learning more about all this stuff. I thought solid axle suspension design was in depth, but shit this stuff is a whole new dimension.
You basically just gave me an extremely simplified version of what I've been reading about this past hour. Thanks!

With anti-dive you just really only need to know a basic condensed amount for front long travel. You can be safe and stick with factory numbers. If you have a lot of shock power you can pull out anti-dive and have your shocks tuned for your driving style.
 

AssBurns

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With anti-dive you just really only need to know a basic condensed amount for front long travel. You can be safe and stick with factory numbers. If you have a lot of shock power you can pull out anti-dive and have your shocks tuned for your driving style.
Yeah I'm nowhere near ready to tackle building a custom LT front suspension. If I do, I'd like to be able to ditch the factory mounts for something a little better geometry if needed. For now, I'm probably gonna stick with stock mounting points.
 
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