Anti-Dive in front suspension

Lately i have been noticing a lot more guys trying to build their own chassis and such.  The thing is...i dont see them built with any anti-dive in the front suspension.  I completely understand why there is anti-dive built into the cars we drive on the road but why arent more of these guys building the frames figuring in the anti dive into the suspension.  My main question to you is how important do you think having anti-dive in front suspension is and why.  I am just curious.
 
 

Edited: 10/14/2009 12:50:33 AM by no1lowr

Untitled I think it’s very important as a pretty large part of the alignment of a vehicle. Depending on the vehicle being built and what you want it to do. The angle its being setup at depends on the size of the wheel and tire and how you want the vehicle to handle. Pretty much it will help the vehicle steer itself, it makes it easier for the vehicle to steer itself and react. if your building a trophy truck u might want there to be zero degrees of anti dive, because your going be jumping it and making turns the entire time on a closed course, and you don’t need it because you are going to be controlling the vehicle the entire time, not to mention its stronger! On any other kind of street vehicle, such as an air bagged custom or hot rod it helps it keep itself straight so it doesn’t walk all over when you hit a bump or are on an uneven road. If you were driving straight and u hit a bump, with zero degrees built into the suspension, its going want to jump all over the place and bump around, but with a few degrees it will just  help keep itself straight. So overall in my opinion it’s very important and I agree, many people do overlook it, most of the time I’m sure it’s just because they aren’t aware of it. For example, on my FORD its been set up at about 5 degrees, this is just a ballpark and pretty much enough to either add or take away a bit, and this may change when we get to aligning it and figure out how the trucks going drive and handle itself, very important to the alignment of the vehicle overall and it should be set up for how you want the car to react when managing itself on the road. Just my 2 cents, hope I'm on the right track of what you’re asking…

 

correct me if I'm wrong but what you are describing josh is Castor, which is just having the upper spindle mount essentially offset from the lower, this helps to redirect the wheels into a straight line.  My understanding of anti-dive in the front suspension is its capability to offset any nose dive during braking conditions.  I didn't design any into my suspension for a couple of reasons, mostly due to the fact that as you add more anti-dive the more your castor changes, also it didn't work into my overall design.  I guess I will have to rely on stiff shocks if I do come across it really being an issue

correct me if I'm wrong but what you are describing josh is Castor, which is just having the upper spindle mount essentially offset from the lower, this helps to redirect the wheels into a straight line.  My understanding of anti-dive in the front suspension is its capability to offset any nose dive during braking conditions.  I didn't design any into my suspension for a couple of reasons, mostly due to the fact that as you add more anti-dive the more your castor changes, also it didn't work into my overall design.  I guess I will have to rely on stiff shocks if I do come across it really being an issue

Josh is totally talking about caster, and you def want caster in just about every vehicle. Mike is correct, and I also didnt design any anti-dive into my chassis. I asked Max about it and he said it wasnt worth it for what I was building, and I agree.

Yeah Josh is definetly talking about caster.  Which is completely different than Anti Diive.  Anti Dive is is the forces of inertia and mechanical resistance that the brakes create thru the front suspension.  On most chassis, the lower control arms are level front to back.  The uppers usually have about 5-7 degrees of angle front to back, higher in the front.  This is called anti-dive, because thru the braking force on the front suspension, the chassis will resist dive (weight transfer to the front). Simetimes the front will even have more Anti Dive than the 5 to 7 degress just depending upon the car and the engineer.  I notice  on your Ford Chassis that the upper arms are paralle with the lower arms meaning there is no anti dive in the front suspension.  Now that was basically the question to Max is why arent more guys building it into their suspensions/chassis/frame.  Is it important for the stuff we build?  Or perhaps he thinks that it is not that important.   

My front setup has no anti-dive... There was a question on why my setup didn't incorporate anti-dive. Here is Max's response:"Anti-dive is a dynamic effect that resists the “dive” force that happens when you apply your brakes. The most common way of creating this effect is by angling the upper A-arm back so that the spindle actually rotates back when the suspension moves up (vehicle gets lower) through its travel. When you apply the brakes the caliper being attached to the spindle tries desperately to rotate the spindle forward while weight transfer is trying to make the suspension collapse thus causing the spindle rotate rearward. These two effects can be setup to completely eliminate any dive caused by braking.The problem that I have with anti-dive on adjustable suspension is that the caster change is not helpful. Anti-dive from the factory isn’t that much to start with, 1° to 2° is negligible and not running it is almost unnoticeable. Someone mentioned the Vette having so many degrees of anti-dive, anti-dive is measured in percentage not degrees and without knowing where the center of gravity is on a particular vehicle, you can’t really know how much anti-dive that vehicle has and on top it off there is more to that equation than just the angle of the upper a-arm."

Thanks Robert...that basically answers my question.  I did mean % when i spoke about the degrees of the upper arm.  My bad.  Thanks for the response it helps.  And by the way your chassis  is coming out awesome!

No problem man. Max might have more to say on the subject. He has been running around with his head cut off the past couple of weeks. Thanks!

I'm trying to remember if I ever got a similiar answer from Max about anti-dive, I know I asked him if it was really neccessary since I was having issues with the castor change if I did it.  Anyone driving a vehicle right now without it that could confirm whether or not they even really notice a difference?   I'm not too concerned about it since as much as I considered building in wasn't going to have much effect anyways and when I drive a mini I'm a totally different driver, I always leave huge gaps since I never know what hood hop and associates in my neighborhood might do next