Why I had the scales I put my dart on them. The RR is about 55 pound lighter with me in the car then the LR. Would extending RR shackle to preload it more help?
The LF is already little higher then RF and its a street car trying to avoid the odd stance and looking for little more bite on the street.

Minitubbed,SS springs, rancho 9000, 28x14.5 hooiser quick time pros

Your car results are normal for BB A body and probably SB also
Raising the rear with longer shackles will probably move the weight forward, not move it back
Raising the RF will shift weight backwards towards the rear, probably add more weight on the LR than the RR Do you have the battery mounted up front in the stock location? If so how about moving into the trunk behind the RR near to the bumper as possible

Battery in rear on driver side, nitrous tank is on passenger side, fuel cell is centered in trunk.
Figured it would try and push front end down, so turn front spring back up and shift weight back to RR
All sounds good in theory lol

How much weight have people shifted on leaf spring car an results in 60'

Tighten lt front torsion bar to raise rt rear weight. it wont take much to adjust the weight difference you have so it should not make the car sit too high on lt side. If not you have to shift battery to rt side.

The difference in your weights from side to side most likely not make a difference in 60"s. What shocks do you have, what springs do you have, what front shocks what front torsion bars. How much powe do yo make what converter. Those are all the things that would have a bigger impact on 60's.

Most of this is just for the theory. This was my first car and always been a street car, owned it for almost 29 years. There is no cage or enough safety equipment to take to a track.

Just to keep the conversation going

Will have to find the SS leaf spring receipt see what they are exactly, they been on the car forever. Rancho 90000
Has alterktion front with QA1 believe it was 600 rate springs.

517 motor made 735hp on 93 octane pump gas back in 2007 been in there for awhile lol have added better headers and changed cam since then. Has a 250 fogger on it just for fun also. ptc 9.5 stall around 5000 was a more nitrous set converter.

Have a buddy that bracket races bringing his Roadrunner over tonight to see how it scales. Runs 11 flat around 120. Might be looking for more advice on his set up.

I would look at getting all the weight I could get on the right rear tires by moving the battery, fuel cell over and so on I added another group 27 battery in my old pump gas (3450 lbs. with me in it) 1971 Duster to help it run faster, especially at the track. It was NHRA legal to 10.00 and I ended up getting kick off at Woodburn 1/4 track for running 9.99 ET through the complete 3.0 inch exhaust system with the air cleaner on
My motor started off as a 511 C.I. 400 block stroker motor with 906 iron heads, 9.25 to 1 compression ratio and a low deck six pack set up, it ended up being 4.375 bore with a 4.300 stroke crank (517 C.I.) and a set of M.W. port size Indy SR heads(10.78 to 1 comp. ratio) with a matching 4500 Indy 400-3 intake and a 1050 CFM Holley Dominator carb.
It was a ladder bar car with coil overs from day one though, I never drove that car with leaf springs

We scaled the Road Runner tonight.
Ended up two full turns up on driver side and down two turns on passenger side, 6 cylinder torsion bars, SS springs in rear. Ride height stayed about the same and driver side is slightly higher then passenger side, almost even with driver in the car. Ended up with 40 more pounds on RR with driver in the seat. Driver under 150 pounds.
hopefully weather lets him test friday night.

Will mess with Dart tomorrow night see what I end up with. Thought of changing to ladder bar for a winter project.

I played w/this on my Dart and one thing for sure, 2 batteries on the pass rear hooked and booked way better that a single and proven at the track. That's about 40 lbs. w/a gel battery and my car is biased more on the dr side and went a 1.33 60 last time out footin to 2500. We played around quite a bit raising the ft. w/a floor jack and watching the rear scale #'s and it's crazy how much they change at launch so if it leaves good and goes straight,they are what they are............

This is a topic I've thought about for a while. A buddy of mine has a set of scales I can borrow to scale my Dart, so I've been wondering about side to side weight and how close it needs to be.

Not sure why the weights changed and forgot to check the scales for zero after we took car off.

You are on the right track, I think the changes you made will help.
I played with this a lot on my F.A.S.T. GTX. Running 10's on stock suspension and G70-14 Coker redlines, I found that the car needs to be level sitting still, level (side to side) at launch, and have a lot more weight on the LF and RR to keep it from lifting the RR tire and loosing traction. Solution: add leaves or half leafs to the RR spring, crank up the LF torsion bar, get the weight on the RR and LF tires. Then loosen the RF torsion bar and de-arch the LR spring to get the car level and drop it down to the proper ride height.

Thanks for advice. Still amazed what you FAST guys do!


I did Some adjusting last night and extended the shackle about 1.25 it helped. Will post scales once I get stuff readable lol.