If you followed my Track Time, Finally thread, this is the last post I wrote, about corner weights. I am looking for feed back. My Dart is 100 lbs heavier on the driver's side with me in the seat at the line .

I figured the car was not set up properly after the best 60 ft drove me left towards the center line. So I borrowed scales and sure enough;
Lf844. Rf. 703
Lr. 674. Rr. 721.
Total weight with driver and fuel, 2942.
After taking 3 flats away from rr, I got
LF. 819. RF. 728
LR. 701. RR. 694
52.6 ,% on front, 47.4, % on back. The left side weight is1520 and right side is1422. So I chose to consider what the tires had to handle side to side in my choice of how much preload to use

Greg,

with 3 flats of preload in the rear suspension, which is a lot for a 4 link, that makes sense the car was steering left on you while the wheels were in the air. Since you scaled it with the preload in it, and then took the preload out of it, I would run the car with the preload where your rear corner weights are almost exact. Scales are crazy when you use them because as you can see, when you change preload, you don't only affect the rear corner weights, but all of the corner weights. How much preload do you have in it to get the rear corner weights that close? If you take the car back out with that setup and it still wants to push left, I would try a neutral preload, and if it still pushes left, you can try negative preload. I would put negative preload in it on the scales to see how much weight it moves around in the event you find yourself adjusting preload at the race track. At least that is how I approach my own. Also, do you have an anti roll bar on your 4 link?

Greg's Dart is a ladder bar car. No 4 link.

Greg mine has about 30lbs more on the RR. Car is 50lbs heavy on the drivers side. Heavy drivers would make it want to go right with no preload. My housing is dead square in the car with no rear steer. The wheelie bar wheels are equal to the ground on both side with me in the car. It'll go well past the 60ft clocks on the rear tires dead straight. After the intitial 6-8 ft t rides the bars the entire time in the air. I'd check the housing for rear sterr.
Doug

Ok thank you Jerico. I didn’t know that.

I’d agree with DVW, check the rear steer.

Thanks Doug and 78. By rear stear you mean wheeliebar adjustment?

How close do you have to be ? Below is our CW's but it's a CalTrac / leaf spring car.
I don't have any issues with the car steering, it will carry the fronts 100+ft most of the time.

I would try it like that and adjust from there. If it drives slightly right add preload till its good. I like to start at neutral with no preload and make the car go straight. Sometimes you can get away with no preload depending on how the weight is distributed. Static weights on scales setting in the garage are nothing close to what it sees when it is launching.Its just an idea. Every car is different too. My car goes straight as an arrow with these scale weights, which are close to yours.

829 715
664 660

Moving 25# is enough that you should see a change.

When cars start doing odd stuff, springs, shocks, joints, etc need to be verified. None of this stuff lasts forever.

Spring seat heights, AR bar tweaks, moving weight, wheelie bars are other ways of changing the corners and/or making the car go straight.. I typically try to use a minimum of preload in the suspension since it creates bind. I want it to be free and use preload as a fine touch up. If I have to use a wrench on a bar, I may go back and do something else to move a few more pounds.

Now that I am aware of my starting point, with good record keeping I can adjust at the track. It was three flats change for the numbers shown, on the right side ladderbar. I borrowed the scales, and it is a fair drive to the owners house. I appreciate the loan very much.

Need to make sure the housing is square in the chassis.

I have ladder bars also. Jack up your rear by the center of the housing. take not of the difference on each tire to the ground. Your preload side will be closer to the ground You can adjust like this at the track and see what you did.

ALSO i see you are 52% on the front. The way your car wheelies and is uncontrollable sometimes. Think about getting it to 53 or 54 on the nose. It might make a big difference in the way the car acts as far as going forward instead of pitch rotating so much

My method for measuring my rear steer is to pull the tires and wheels off the car. Put the weight on the rear end with jack stands. Take plum bobs and hang them off of the front of the rotor. Measure from the string to one of the holes in the ladder bar bracket. Do that on both sides of the car and it will give you an idea if the rear end is pointing in one direction or the other. Or if the measurements are the same (within 1/16”) then it likely has no rear steer. This is just my method and others have their own way. Tim Mcamis has a good video on YouTube to watch for rear steer that may help. Only thing is, his cars are all tube chassis pro mod cars that are not unibodies. So I keep that in mind.

Make sure you weight is in the seat if you’re outside of car. On mine I had 3 corners the same and driver front had about 60 pounds more. Unless you add weight front or back the back or front will stay the same weight no matter how much you jack the flats, AND the only way a ladder bar can ‘adjust flats’ is one bolt has to be out on housing even with an adjusting heim (easier) especially coil over shocks if you have them. Car was 2160, me 250, lead 80, gas, right at 2500, hooked on snot

Fuel and battery are in front of the radiator. Aluminum block is the culprit. Nothing else to move now. It worked great at 9.60s, but that was a long time ago.

My only response is 3 flats is a LOT in any car.

Greg, check the diameter of each rear tire. Probably not it, but something to eliminate and is free and easy.

Al, it was off quite a bit to start when I first weighed it.. I am certain it is less than that from neutral, based off original corner weights
EDIT: I REDUCED the bias by turning three flats. So my guess would be it was about six flats from neutral.