Bob,

thanks for the compliment

i have the fabrication down, but im still learning a whole lot about suspension. knowing the fact that there is sooooo much to be had from a properly setup suspension, moreso than engine output 90% of the time, im absorbing all that i can.

being able to do all this hands on is what really helps, building and talking with people who know (Joel can setup a Formula SAE suspension and design it like its his job) is helping immensley

Dustin

 

well i would imagine that the FWD that would try a setup like this would have skinnies in the back, so it probably wouldn't be anymore scary (maybe less so) than the fact that RWD drag cars have little weight and no front contact patch on the front of the car!

 

sorry i lost track of this thread guys... my subscription disappeared...
anyway

I know the norm for FWD is to do skinnies.. or at least as small as possible in the back. The problem with fwd set ups is it is very easy to loose your drivabiltly, especially when you do slicks in the front and skinnies in the back... Thats why most street going fwd cars just have really stiff springs and what not to avoid any body motion. There has to be a better set up...
Just to show how much I know about drag racing, I didn't even take into account the gyocopic movements... I was just thinking traction on the back tires due to weight transfer...

what do you guys mean by anti geometry?

When I started this thread, I was hoping to compile alot of very easy to understand information. So, if you would be so kind as to dumb it down, still go in depth and all that good stuff, but dumb down the "technical terms" I'll try and ask all of the dumb questions so its easier to understand, which will be easy for me, cuz i really don't know. my knowledge is limited to fwd gets super stiff and slicks in the front. RWD gets softer in the rear, lots of squat, and slicks in the rear...

 

Anti-geometry refers to anti-dive or, in this case, anti-squat geometry that basically takes a portion of the forward acceleration forces off of the springs and into the suspension linkages. You can design the suspension so that part or all of the force from the acceleration is absorbed by the chassis and doesn't cause the springs to compress. For example, if you have 75% anti-squat geometry, only 25% of the acceleration force for go into the springs and (for linear wheels rates) the car will "squat" only 25% as much as it would with 0% anti-squat. Anti-squat doesn't reduce the amount of weight transferred, but it does reduce the time it takes for the weight to transfer and the car to reach its steady-state condition. However, the more anti-geometry you add to the suspension, the more jerky or harsh the accelerations become, due to the suspension not use the springs and dampers to soften the acceleration. Many vehicles come with anti-geometry in order to have a soft ride but not have the car dive excessively under braking.

In order to get a lot of traction on a RWD, the car doesn't need to squat a lot, it just needs the weight transfer.