wiggle of the starting line.

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Cudafever said:
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.
Click to expand...

there is no need to “ stall it higher”
It would be very unusual if the car was any faster leaving off the foot at 1500 or 2000 than 2800 or 3000.
Just find a nice relaxed, repeatable spot to launch it.
It might well be the convertor is somewhat tight( not necessarily a bad thing) that makes it push at 2800, and nothing to do with your brakes.
Making a run at the convertor at a lower Rpm can sometimes make it hit harder , than having the suspension all tensed up.
 
If you slow the video down, you can see your front tires turn to the right as they are coming up.
 
Bump steer my be a problem as i have lowered the front end 3 1/2 inch. 2 of them inches after i had it aligned.
I need to check my toe and see how much my tie rod my be going up hill at ride height................

I have lots of thing to check and many that i hadn't even considered.:poke::thumbsup:
 
jaws said:
If you slow the video down, you can see your front tires turn to the right as they are coming up.
Click to expand...
Well if the suspension is turning the wheel to the right.......that would sure make the *** end kick to the left.
 
I am kind a thinking out loud........ but if the tie rod is going up hill "because the car height is lowered below factory specs", and changed the geometry.......
So, this make the tie rod shorter......As the suspension goes UP........the tie rod becomes Longer,.......and would make the car or wheel turn out, or steer left..........Hmmmmmm the right front wheel would turn out as well causing the car to go right, Right????
So i guess which ever front tire has the most weight on it at full launch/lift would be the steering tire.........
That could make sence why it goes left and then right......in theory anyways.
 
Need to set the car at ride height, then put a floor jack under the K frame. While jacking up the car check it for toe in change.
Knowing someone with an alignment rack is a plus
 
sam65 said:
If you are running a stock style seat and the launch plants you back in the seat you are going to move the steering wheel.
Click to expand...

That is defensively a "thing". when i was only running high 15 in the 1/4 i broke my seat back and had a old racing helmet behind the front seat keep it from being a recliner :lol:
Had to strip my seat completely and have my buddy weld it all back together. Yes i'm still racing in that seat.
 
Cudafever said:
I am kind a thinking out loud........ but if the tie rod is going up hill "because the car height is lowered below factory specs", and changed the geometry.......
So, this make the tie rod shorter......As the suspension goes UP........the tie rod becomes Longer,.......and would make the car or wheel turn out, or steer left..........Hmmmmmm the right front wheel would turn out as well causing the car to go right, Right????
So i guess which ever front tire has the most weight on it at full launch/lift would be the steering tire.........
That could make sence why it goes left and then right......in theory anyways.
Click to expand...

THIS STATEMENT IS WRONG. so i'm up dating it.

The tie rod is mounted to the back of the spindle,,,,,, there for, as the tie rod getting longer it would turn the L front Tire to the right and cause the *** end to go to the left( As it is doing)
Soooo that makes a lot of Sense............I have got to get out to my garage and find some answer..........or create more questions:D
 
Well as i said more question then answer.
The tie rod is in a down hill rack(as i thought it would be) but as the suspension goes up(floor jack under the K frame) the tie rod becomes even steeper in its angle not, not less as the suspension goes up as i had thought. Spindle tie rod end down or lower then center link bar end of tie rods

However, the toe is at 0 (or as close as i can tell with a 2x4 and a tap measure) at ride height. Jack up until one tire unloads enough to start to slide inward. measure again, and it is toe out 3/8 of a inch.

So this is what don't make sence to me. as the tie rod goes down it becomes shorter in length horizontal. So, in my mind it should toe in as the suspension goes up. BUT it did not, it toe out.
EDIT: I have to keep reminding my self that the tie rod is on the back side.
Shorter would cause it to toe out.:BangHead:

I'm not a suspension guy at all but i don't think this is my problem with it swinging the *** end out to the left at launch.
 
Before i rebuild my clutch style posi, it still worked, but when i would torque my wheels, with the car in the air and in park.
The right side would turn the wheel 1/8 of a turn before locking up and the drivers side (L) would not.
Just went out and re torqued my rear slick. No movement on either side in forward or revers directions. Clutch Posi is in good shape CHECK!

Slick diameter, left to right, Is the Same. CHECK!
 
Sublime one said:
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.
Click to expand...
Agreed. I shouldn't have said "back off quickly", but you need to do something quickly, as the wall is getting closer fast! Best thing to do IMO to bring front wheels back down is to shift into the next gear.
 
The only thing i haven't check is the rear end to the body.
I lowered my front end by equity turning each torsion bar.

I think i'm going to have to do some staggering to get it right/launch straight.
But first some more videos, in car and out. but that's a month a way:(

I know some of you are saying that it's not that bad or no big deal.......And it's not!
But i need to get some chassis tuning learned, and in my tool box(so too speak) before it does pack that front tire.
 
So we had a small tire/ big tire street outlaw type race a Hypoxia today.
you guys said that i should video the back of other race cars(being a bit of a smart as:)) it was kinda interesting.
well here you go.
 
Unfortunately i set them two short video up as "shorts" on you-tube.
What i learned is that you can't edit if when you do it that way. aka slow it down, speed it up.

So i have been playing it on my phone were i can slow it down......
I sure wish i would have shared this video with the Green Cuda. He through more boost off the line on that run and blew the tires off of it.
Man there is so much more to the story then that. I believe the wheel bar was what started the loss of traction, BUT it was already heading to the wall at that point. The tires unloading (spinning) allowed the front end down so he could steer away from the wall. as the body rolled to the RR tire, it bit and the LR tire when into a little tire shake or waffling affect(unloaded now). bringing it back on to the track. and then wiggling back and forth all the way to the end of the track.

The green dart, although looking uneventful, in slow motion i noticed that the left front tire turned to the right........did he turn it to the right at launch????? or did the suspension do that. Hmmmm

MinnesotaMopar said:
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...

Thanks for that @MinnesotaMopar I hadn't even considered watching other race car suspension work.
More educating then i would have thought.:thumbsup::thumbsup:
 
Ok finally the race happen and i have video.......

Well the video isn't going to help out much on anything that we have been discussing above.
Every run but the last on was straight/dead hook/little need for input from the driver.
The last run down the track was a total **** show and no DATA to show it. Gave my buddy my phone to video from the front....Phone timed out so he couldn't video. i turn on my data recorder for the first time all day......turn off car before stopping the recording, which corrupt the chop and loose all data.

Launched, and the rear end washed out to the left then to the right, hit 2nt gear and it straightens out......with not a single piece of data to go back and look at.:( o well it is what it is.

So on a lighter note. here is a 4 minute in car video of my runs.
 
Cudafever said:
Unfortunately i set them two short video up as "shorts" on you-tube.
What i learned is that you can't edit if when you do it that way. aka slow it down, speed it up.

So i have been playing it on my phone were i can slow it down......
I sure wish i would have shared this video with the Green Cuda. He through more boost off the line on that run and blew the tires off of it.
Man there is so much more to the story then that. I believe the wheel bar was what started the loss of traction, BUT it was already heading to the wall at that point. The tires unloading (spinning) allowed the front end down so he could steer away from the wall. as the body rolled to the RR tire, it bit and the LR tire when into a little tire shake or waffling affect(unloaded now). bringing it back on to the track. and then wiggling back and forth all the way to the end of the track.

The green dart, although looking uneventful, in slow motion i noticed that the left front tire turned to the right........did he turn it to the right at launch????? or did the suspension do that. Hmmmm



Thanks for that @MinnesotaMopar I hadn't even considered watching other race car suspension work.
More educating then i would have thought.:thumbsup::thumbsup:
Click to expand...

The Cuda definitely needs to fix the rear suspension on that dude ! Years ago I raced a 71 charger ! 6.90 1/8 mile car ! 1.50 short time ! 99 to 100 mph ! It would do the same thing your car is doing ! Had a buddy ask me if I had checked my wheel base on the car ! So I measured it ! I was 1/8 off ! So I corrected that ! The car never did it again ! I didn’t see any short time or et from it, but the car went straight out of the gate ! If yours is straight , mite add another spring clamp to the right spring.. see if you can get the right rear to bite a touch harder ! Something else to check ! I enjoy trying to figure out these things !
 
Rmoore said:
The Cuda definitely needs to fix the rear suspension on that dude ! Years ago I raced a 71 charger ! 6.90 1/8 mile car ! 1.50 short time ! 99 to 100 mph ! It would do the same thing your car is doing ! Had a buddy ask me if I had checked my wheel base on the car ! So I measured it ! I was 1/8 off ! So I corrected that ! The car never did it again ! I didn’t see any short time or et from it, but the car went straight out of the gate ! If yours is straight , mite add another spring clamp to the right spring.. see if you can get the right rear to bite a touch harder ! Something else to check ! I enjoy trying to figure out these things !
Click to expand...

Thanks, good info. I haven't yet checked the rear for square.
At this point, adding a clamp is out of the question as there is not enough clearance between the slicks sidewall and the spring for a spring clamp.

I think i have found the problem........just haven't decided how i'm going to fix it.
 
So finally went out and measured my rear end. Was not even 1/16 of a inch off. as far as a tape measure goes it was perfect.
Now to what i thing is some or maybe all of my problems.
 
I don't think this look right to me.




Pinnion snubber.jpg

:BangHead::D
 
I think i will try and glue it back on with some windshield urethane.
 
A tube of Urethane and the gun to apply it was more then just buying another one.
UPS said delivered Saturday by 7 pm.
Still haven't decided if i will put my cheater slick on and race the 20th. Or keep the slick on and wait for Sep 17.
Replacing my pinion snubbed every 20 years.......that's not bad, right!:D
 
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