OK this is what I've learned. A few weeks ago we went out to T/T. Track was so so. 1.32-1.35 60 fts car ran low 9.30's. When we saw the housing bouncing on the video we thought the logical step was to tighten compression on the rear. The first movement of the axle housing will ALWAYS be downward. So the goal was to keep the housing from bouncing back up. Went back out on race day. I made the change, it still came up, I tightened even more, no help. Spent the day in the 1.40's. So on to the next step. It's still spinning so I raise the ladder bar to hit the tire harder. Housing still bounces car can't even make it to the 330 mark, 1.45 60 ft. Disgusted as I have a set of Holley's replacing the Eddy's, it should be quicker. Listening that it is the carbs, bar location, tires, etc. I order new tires. Put the bars back in the middle hole. First hit 1.26 60 ft. Eureka, it's fixed, no quite so fast. goes 1.27, 1.35,1.28, 1.29. I throw out the 1.35 assuming it's something on the track, wrong. Onward to the Quaker City Mopar race. Numbers are not great as I'm deep staging running the .400 tree. Hooks OK until the final. Fortunately my opponent is broke. It kills the tires to the 330, but I get the win. Day 2, loosen the front trying to get it to pitch rotate back, no help but we go to the final again. This time not so lucky. Kills the tires, car misses the dial by .20. I blame it on hot track temp, 140 degrees, wrong. On to the Northern Class nationals. First hit is what you see in the video, then garbage. That afternoon we start to look back. Maybe that Friday T/T wasn't as bad as we thought. Maybe I have the rebound to loose allowing the housing to hit the tire to hard and the tire itself is bouncing, not the housing. We tighten the rebound on the Koni's to -5/12 from full tight. Go back to the old compression setting and add one click, now -9/12 from full tight. We dynoed this pair of Konis. They have a very tight compression range, thus the loose setting. Last year the car had QA-1 street shocks on the front set at -2/12 from full tight. It now has Afco doubles on the front. To simulate we run compression full tight to keep it stable from wheel stand. Loose rebound has never shown that it works well with this car. Yanks the front hard and then spins. So the front rebound is now at -30/40 from full tight. The results speak for themselves. Went back to back 9.17 in the heat. It has picked up .02 at 330 with consistent 60 ft. We went beyond the tuning window. Hit the tire WAY to hard and spun. Now that were back close a LITTLE adjustment at a time. There's more in it.
Doug
