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travis steele
07-06-2015, 05:59 PM
Can to much caster on the right front bind a car up. Bumped the wall a few weeks back killed the lower replaced it with a new one an haven't been fast since had the right spindle checked it was ok can't seem to find where I went wrong.

let-r-eat
07-06-2015, 09:16 PM
Yes it can.

FlatTire
07-06-2015, 09:57 PM
It will make u tight on early entry. Car won't want to turn in.

7uptruckracer
07-07-2015, 07:16 AM
Make sure your mount is ok. Make sure you reset your caster according to you builder and use the correct piece to actually set the caster

PushinTheLimit
07-07-2015, 09:18 AM
It was my understanding that the bigger caster split between the RF and LF, the better the car would turn. Is that the case or completely wrong? Or I guess is there a point to where you can have too much caster in the RF?

Matt49
07-07-2015, 09:55 AM
It was my understanding that the bigger caster split between the RF and LF, the better the car would turn. Is that the case or completely wrong? Or I guess is there a point to where you can have too much caster in the RF?

Caster split (more RF than LF) will make the car "easier" but it's a bit of fools gold.
Adding caster to both sides makes the steering wheel want to go straight because both wheels are always trying to turn inboard. Removing it from one side (like the left) will make the other wheel dominant on inboard steering if you simply let go of the wheel. So it "feels" like it turns easier because you just let go of the wheel and it immediately turns left. This was a much bigger deal before everybody had power steering and remains a bit more or hot topic on pavement cars.

25drtrkr
07-07-2015, 01:20 PM
Also, when adding positive caster to the lf, you are increasing the wheelbase at the contact patch, but with the wheels turned to the right, you are increasing wedge.

And....check the instructions for your gauge. Some call for the wheel to turn left and some right when checking caster. LOL, this almost led to a huge fight one night at our shop!

billetbirdcage
07-07-2015, 02:54 PM
And....check the instructions for your gauge. Some call for the wheel to turn left and some right when checking caster. LOL, this almost led to a huge fight one night at our shop!

You'd be surprised how many times I seen that one, instead of positive caster they have negative in both sides.

It happens even to big name drivers from time to time, funny story. Not going to mention his name but eventually became a touring USMTS driver with major car owner, but this was before then and happened his first year in a modified. He was pretty fast in a street stock and moved to modifieds but just wasn't any good and struggled pretty bad. He was so bad, that people said it was him and not the car and he just didn't have what it took to make it in the mod division.

One night at some races a friend of mine came over and said he hot lapped his car for him and asked me what would cause the car to pull right. So I went over and just eye balled down the ball joints and low and behold the upper B/J was in front of the lower B/J on both sides. Told him: "Well, there is your problem".

He didn't have a gauge with him, so I told him I'd just eye ball it but I'd get it close enough that way. So I adjusted both sides where the upper was roughly 1/2" behind the lower on the RF and about a 1/4" or so on the LF and reset the camber roughly.

Well, he won his first mod race that night by winning the heat race and leading every lap in the feature.

Always and I mean always eye ball down the ball joints when done to make sure the upper is behind the lower for positive caster, it only takes a second and can save you a ton of headache.

billetbirdcage
07-07-2015, 03:05 PM
Can to much caster on the right front bind a car up. Bumped the wall a few weeks back killed the lower replaced it with a new one an haven't been fast since had the right spindle checked it was ok can't seem to find where I went wrong.

Not sure how you or someone checked the spindle, but they are notorious for not be 100% after they are welded and you could have bent it and that actually made the alignment of the ball joints better with a typical spindle checker, but the inclination is way off now.

If you notice a difference in handling or all of a sudden a lack of drive (this is what I found is typical with a bend RF spindle), it's best to just swap out the spindle instead of struggling for several weeks then changing it cause you tried everything else.

Just my opinion

Matt49
07-07-2015, 05:15 PM
Not sure how you or someone checked the spindle, but they are notorious for not be 100% after they are welded and you could have bent it and that actually made the alignment of the ball joints better with a typical spindle checker, but the inclination is way off now.

If you notice a difference in handling or all of a sudden a lack of drive (this is what I found is typical with a bend RF spindle), it's best to just swap out the spindle instead of struggling for several weeks then changing it cause you tried everything else.

Just my opinion

I've considered making jigs using known good spindles. Not because I want to build my own but just to have something to set it on to quickly see if it is where it should be after trying to knock the fence down.

zerolm
07-11-2015, 10:23 AM
That's exactly what I do. I can tell you that pretty much every time the steering arm itself is what bends. Most of the time I will put it back in the correct place with my fixture, strengthen the weak spot and put it right back on the car with confidence.