wiggle of the starting line.

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Cudafever

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Got my buddy to us my phone and get few run of my car.

It is amazing that you can react to something and your brain didn't even drop a note that it happen.
Each clip is from a different run.
The 2nt one is in "slow mo" from the front.
O and that funny stuff hanging from the front:eek: is just loose header wrap.:D
 
Those appear to be a pretty good launchs. No unusual bouncing or bobbing of the front or rear suspension. No apparent wheelspin.

I am guessing that you do not have a spool in the rearend. Without a spool you will nearly always get a slight difference in torque applied to each rear tire, even with a limited slip differential. That difference in torque will cause the vehicle to slightly steer to one side or the other. For guys that have been driving muscle cars on the street for years with that "wiggle" the correction in the steering wheel is so second nature that I'm not surprised that you are not aware of making that adjustment. I don't think it is a problem untill you start pulling the front tires off the ground at launch. Then it will be a real important problem to fix or else you will end up in the wall right at the launch. A rebuilt differential would help, but a spool is the best solution for on the track.

Your rearend might also be slightly misaligned with the car. Or perhaps a bad front tire alignment causing you to stage at a very slight angle. So could slicks that have different air pressure, or different rollout circumferences cause this. Or even just a minor variation in traction of the track from side to side. But in this case I think the most likely cause is the simply the limited slip applying differing torque to the each slick.

All that said, you should video other fast cars from the rear at the launch. You will find that many of them have some wiggle as they go launch and go down the track, depending on how their suspension is reacting and the traction under each one of the slicks. And even defects in the track surface can cause a car to move around.
 
It looks to me like it's lined up crooked to the left.
 
You can name the car " the wiggler" atleast
 
MinnesotaMopar said:
Those appear to be a pretty good launchs. No unusual bouncing or bobbing of the front or rear suspension. No apparent wheelspin.

I am guessing that you do not have a spool in the rearend. Without a spool you will nearly always get a slight difference in torque applied to each rear tire, even with a limited slip differential. That difference in torque will cause the vehicle to slightly steer to one side or the other. For guys that have been driving muscle cars on the street for years with that "wiggle" the correction in the steering wheel is so second nature that I'm not surprised that you are not aware of making that adjustment. I don't think it is a problem untill you start pulling the front tires off the ground at launch. Then it will be a real important problem to fix or else you will end up in the wall right at the launch. A rebuilt differential would help, but a spool is the best solution for on the track.

Your rearend might also be slightly misaligned with the car. Or perhaps a bad front tire alignment causing you to stage at a very slight angle. So could slicks that have different air pressure, or different rollout circumferences cause this. Or even just a minor variation in traction of the track from side to side. But in this case I think the most likely cause is the simply the limited slip applying differing torque to the each slick.

All that said, you should video other fast cars from the rear at the launch. You will find that many of them have some wiggle as they go launch and go down the track, depending on how their suspension is reacting and the traction under each one of the slicks. And even defects in the track surface can cause a car to move around.
Click to expand...

Interesting, no it don't have a spool, clutch style unit that i rebuild last year.
If i could muster another 10 or 15 HP out of it i thing it would be packing the front tires. And is why i have been taking videos.
When the track goes away it does spin off the line. Not a blow the tires off spin, but a spin. And that's when the car get out of hand as you can see in ?????3d launch.
both slick at 15 psi. circumference is something i should check.

justinp61 said:
It looks to me like it's lined up crooked to the left.
Click to expand...
could be....I'm a one man band, and i try to point it straight each time.

If you look close from the rear, it launches straight and true. then something changes and it heads right.(like a half of a turn of the slick it starts) Is it launching straight but not to the track and i'm making it swing?...........It is possible..........
Next time i will have someone video from the outside and set up my gopo on the inside focusing on the steering wheel. that should answer that on.

MOPARMAGA said:
You can name the car " the wiggler" atleast
Click to expand...
I have never came up with a name for my car.........But i don't think that is the one.:D
 
So here is what i think is going on, or what i am seeing, feel free to comment

I think that my front end is going up to quickly(rebuild the hole front end with low friction components). My front shock can be set at 3 setting and they have all way, been on the 90/10 setting. Think i need to slow down the front end rise. I thing they are topping out. but not at the same time. You can see the R front stop travel, then the L front. I thing it is unloading(when it tops out the suspension) and reloading the rear suspension at different intervals.
 
If you can get it to lift the tires off the track you will find out quickly if it is the front suspension or the rear. Ask me how I know! And be prepared to back off quickly!
 
Leaving off idle? Have you tried to load the converter a bit? I don’t think it is topping out too quick. It’s not upsetting the car. The steering will get very light and on launch you would be surprised how much you will turn the wheel without realizing it. You might try and move the seat a bit closer to the wheel. Gives your arm some “slack” to help with you turning the wheel. I also thought you look crooked. I see you do load it some.
 
I have left off of at a idle, works but my reaction times go's in the toilet. my brakes won't hold me much past 2800 rpm(brakes need work)
I really felt i was on the verge of lifting the front tires off the ground, but have yet to feel a soft or light steering.

I have read that you need to have the front end slowly come up and not stop until, at-least the Christmas Tree. aka 1 to 2 sec's into the run. Mine is full extended in like .2 or .3 of one second.

I will have to notice my arm/ body position in race ready position.

I really think that i'm lining my car up straight.......but it dose look like i'm not, in the video.
 
If it smoothy tops out and doesn’t upset the car, that’s the goal. Now if it does that and after it tops out it spins the tire. I would slow the nose down and extend the time it is transferring weight. It might start to spin a couple of feet after the hit then, because it will have transfer less weight earlier on. Easy to see the difference in steering effort. Jack it up until the tire is just touching the ground. Get in and turn the wheel, remember it will be a good bit easier when the car is rolling. Don’t knock it off the jack. Stands would be smart. Adjusting the nose will be tough with the limited setting you have.
 
Also it could be the alignment. As the wheel drops down on the launch the toe changes. The tie rods effectively gets shorter which toes the front tires out. Then whichever tire grips better or hits a seam or any number of reasons, that tire steers the car. Then it can change to the other tire and back and forth. With it jacked up measure toe with a tape measure. Tire groove to the corresponding other tire groove. Do it in front of tire and back. How much different
 
I have to agree with a couple of the others on here, it looks like the car is not straight to the track and you will naturally ease it back on launch to straight and the car will wiggle on those 2 ply slicks, looks like you can see some steering input on the front tire in a couple of those shots. The front end speed seems ok to me, my policy has been to get it up as fast as possible until you get going too high off the ground then you need a bit of control to slow it down
 
RockinRobin said:
If you can get it to lift the tires off the track you will find out quickly if it is the front suspension or the rear. Ask me how I know! And be prepared to back off quickly!
Click to expand...
And that right there folks is how you crack your fiberglass front fenders. Ask me how I know. The chowderhead behind the wheel on my Cuda did the infamous panic lift thereby bringing front end down a bit unceremoniously if you will.
 
furrystump said:
If it smoothy tops out and doesn’t upset the car, that’s the goal. Now if it does that and after it tops out it spins the tire. I would slow the nose down and extend the time it is transferring weight. It might start to spin a couple of feet after the hit then, because it will have transfer less weight earlier on. Easy to see the difference in steering effort. Jack it up until the tire is just touching the ground. Get in and turn the wheel, remember it will be a good bit easier when the car is rolling. Don’t knock it off the jack. Stands would be smart. Adjusting the nose will be tough with the limited setting you have.
Click to expand...
When i'm running my cheeter slicks aka street tires. I will stick long enough to move about a foot or two and them goes up is smoke.
If i feather it out of the hole, i can't give it full throttle until after the Christmas Tree.
bump steer is defiantly something to consider. Some thing ells i will have to take a look at.
 
But it always kicks the *** end out to the left and then i correct with the wheel.
The other thing is that this is an old air port and the surface is crowned. in other worked it slopes to the left on the left side and right on the right side. But, both lanes it kick the *** end to the left of the starting line.

But i agree, the video of me in the right lane, it look like i'm pointing it at the Christmas Tree.
 
You're getting another dimension to straight line racing. More fun! :lol: The track looks a little greasy. The passes weren't during competition so maximum traction and track prep aren't happening. Are you just cleaning your tires or are you getting them heated up good? Have you tried loading it against the convertor a little more? Just spit balling? Sometimes you have to try a dozen different things before you find the right combination.
 
o yeah 3d gear burn out up to the starting line, lots of smoke.
I can't stall it much higher with out better brakes.
 
Yeah, if it really picks up the tire and you feel the need to do something, like there is an emergency, not going straight, etc. Shift into high gear and stay in it. You’re trying to bog the motor. Softest way to put the nose down, but that takes time and space. If you have neither you kinda run out of options. The worst thing to do when it surprises you with how high the front end is in the air is to lift. Easy to say hard to do.
 
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