'67 Camaro SCCA build

[GregWeld]

Well.... I don't really know anything about suspension ---- I just noticed that huge (IMHO) side to side movement.

I know that I've set up panhard bars that at full suspension travel move as much as 1/8th inch off center line --- so a total of 1/4" top to bottom.

I cut a tire on my race car -- and we search all over for the cause and never did find anything wrong -- and my tires are pretty close to the fender lips in the rear.

And you can see how close they get under load in the front... But we're road racing not auto crossing which is really going to toss the car around side to side.

[Matt@BOS]

I too am surprised at how much it is moving, not laterally, but rather how everything seems to be swiveling, or as Todd said, it almost "looks like the front tires turning." I'm guessing that attributable to bushing flex, right? What kind of bushings do you have. I'm sure whatever you have has been mandated by the rule book.

Matt

[Flash68]

4 wheel steering?

[j-rho]

Originally Posted by Matt.A

I too am surprised at how much it is moving, not laterally, but rather how everything seems to be swiveling, or as Todd said, it almost "looks like the front tires turning." I'm guessing that attributable to bushing flex, right? What kind of bushings do you have. I'm sure whatever you have has been mandated by the rule book.

Matt

At present it only has leaf springs for fore/aft and torque reaction control. They are composite of decent rate (250lbs.) for the rear corner sprung weights (<500lbs.), but aren't enough to keep things under good control.

Greg, the motion you are talking about is axle lateral movement through pure vertical travel - the watts link eliminates this movement. As the car rolls about its rear roll center, on the outside rear corner, the outer fender lip tends to move "away" from the tire (since it is well above the roll center height), and the inboard top of the tire gets closer to the inner fenderwell.

[Sieg]

http://www.hotchkis.net/swivel-max-b...6874-nova.html

[GregWeld]

Originally Posted by j-rho

At present it only has leaf springs for fore/aft and torque reaction control. They are composite of decent rate (250lbs.) for the rear corner sprung weights (<500lbs.), but aren't enough to keep things under good control.

Greg, the motion you are talking about is axle lateral movement through pure vertical travel - the watts link eliminates this movement. As the car rolls about its rear roll center, on the outside rear corner, the outer fender lip tends to move "away" from the tire (since it is well above the roll center height), and the inboard top of the tire gets closer to the inner fenderwell.

I'm not 'arguing' right or wrong - because I really just don't know..... and I wasn't trying to open up a discussion on right or wrong ---- I was just merely shocked at what I was seeing.

I'm going to have to put my GoPro on the quarter in October at Thunderhill and see if my car does this much!! I know my car handles fine --- and obviously your's does as well! You've got some great accomplishments with it (and yourself as the driver!).

What I was thinking was that --- if the body "rolls" that much (and that's not the correct term) side to side -- then someone with a different shaped wheel well might be close to cutting the sidewall in a turn if they're close to the lip to begin with.

I have the Maier rear end suspension on my Mustang --- on leaf springs --- so now I'll have to tape it just to see. After that I might have to hang up my shoes because I might scare myself!! HAHAHAHAHAHA

[j-rho]

Slapped this together in mspaint, perhaps it will help visualize the chassis/axle interactions a bit-


Thanks for the props Greg! Car is still quite a ways from where it could be, which I'm hoping is the same as "where it needs to be" to be really competitive.

[GregWeld]

Good visual graphic!