After looking at a lot of Spyder photo's, it seems as though a majority of them look to be lower in the rear end than the front. Is there a reason for this ? Is it for performance or just a preferred look..............Aircooled Water Bruce
No caster shims.
Ed........I don't understand your comment..........Bruce
It's a joke, Bruce. If the back end is lower than the front, there's natural caster (without shims).
When the Spyder is level, the front arches appear to be higher. They are cut this way to accomodate the turning front wheels as on most cars.
Original Spyders with 16" wheels have the rear wheels tucked way up.
Typical me. I overthink or under think things. Sorry Ed, I just didn't get it. However, A Spyder lowered in the rear would give it more positive caster. These cars are supposed to have negative caster for better handling so here I am again, wondering why I see a lot of them with the rear sitting lower. I'm looking at under the car between the wheels to get this reference. The cars are not parallel to the ground..........Bruce
I think you really are confused a bit, Bruce.
Caster: you want positive caster. It makes the steering self-center and gives high-speed stability. Think the angle of the head tube on a bicycle, the lean back causes the front wheel to want to go straight ahead. Caster is the angle that the front wheels pivot at from vertical, through the two ball joints. On a typical Spyder you're stuck with what the chassis builder welds the beam at.
Camber: The lean of the front tires toward or away from each other, top to bottom. Toward each other is negative camber, away is positive. Negative gives you a flatter outside tire in a curve when the car is leaning toward that outside tire. Too much negative camber can hurt braking, so don't go crazy. I run about 1.5 degrees negative in front. The rear is around 3 to 3.5 degrees negative to get the right ride height with the swing axle.
Toe: Toe-in is when the tires are closer together at the front than the back, as in not quite parallel when going straight. This gives self-centering and stability as well. I run 1/16" total toe-in front AND rear.
My car sits pretty level compared to most.
Nah man. You want a little negative camber. That's the wheels A-ing out a little, with the tops a bit closer to each other than the bottoms, when viewed from behind or in front. /------\ like that. (but waaay less!)
Caster is the tendency for the turning axis to be other than vertical. Positive setting the top behind the bottom, negative the top in front of the bottom. Positive caster keeps your wheels wanting to go straight; negative makes them easier to change direction.
Danny's explanation is the right one though. If you look at both real and fake Spyders in profile, you'll see the floor tends to be very close to level. The fender arches' relation to the tops of the tires can lead one astray.
This is correct:
Most replicas are set a little lower, mostly because guys are running 15-inch wheels with low profile rubber, which gives them less sidewall and concomitantly less height, like
(edit: and now I see Danny beat me to it...hey but I got pics...).
I'm embarrassed again. Got to thinking again and that's dangerous ! Positive Caster is the person who makes sure the best people get picked for the part. Negative Caster is the one who doesn't or, in some cases, has a reputation like Harvey Winestein ?
Anyway, thanks again guys, for correcting me. Again, my mind did a flip flop. So what your telling me is that it's an optical illusion and to look for horizontal parallel between front and rear wheels ?
Ed...The blue car looks perfect to me..............On to the next thing............Bruce
Yes, look for the floor parallel to the ground.
The blue car is 550-0051, the one I'm trying to copy. It looks perfect to me too.