Fresh post, fresh info for stick cars.
After playing around on a slippery non-prepped track all summer, I decided to retune my
suspension differently as all the tricks I was using before really weren't working on my toploader car. Instead of doing just one change at a time (like you are supposed to do), I made several changes so as to start an all new baseline.
First I bought new 26x10x15S MT ET drag slicks. Note the "S" on the end which stands for Stiff Sidewalls. After lots of research of other manual transmission cars, I discovered that the Stiff Sidewalls work very well in that application. Previously I had been using regular 26x10x15's MT ET slicks with only limited success. These things are great and they do not waddle like the old slicks would in the pits plus the car feels much safer on the upper end of the track.
I discovered through some videos that both my rear tires had some serious wheel hop and stiffening the rear shocks did not help, even though I have Caltracs. I decided to drop my Caltrac bars to the lower-most setting to soften the hit, plus I also adjusted the preload to 1/4 turn on both sides.
The final thing that I did, kid you not, was to put 50lbs of sand in the rearmost part of trunk under the spare tire.
The result of those 3 changes was that I can now launch at a much higher RPM and the car seems to jump out of the hole when the clutch is dropped. My 60'ers went from typical 1.72's or so down to the low 1.6 range and I have touched the 1.5's several times with a best of 1.581. I feel that is pretty darn good for an NA stick street/strip car. An added benefit has been that my ET's have also improved tremendously--they were in the 11.6-11.7 range all year, and now I have had several 11.25-11.27's runs.
A negative from the increased traction is that I went through a period of breaking the drivetrain on every outing. The first weekend I twisted the input shaft to the SB toploader. I replaced it and went racing the next week only to twist both 31 spline axles and break my 9" True Trac. I bought new 33 spline axles and a spool, put it all together again, and twisted yet another input shaft on my first launch. I seriously think that I am getting decent traction now. LOL