My cursed weekend history continues, Update

[dvw]

My wife told me this morning when I left. "You know what this weekend is?" Yes its the same weekend I've broken parts or had issues for 5 of my 13 seasons with this car. Water pump (though we fixed it and won). Pinhole in #6 intake port causing the engine to hydralock. Broken ball stud on the carb in the burnout box. Broken forward clutch carrier in the trans. Broken ring gear on the converter (brand new 8 runs). That brings us to today. Milan's renovations aren't complete. So I made the trip to Lapeer international. Never run this car there. The track is plenty long, well prepped, but the wals are 5 foot closer to the centerline. Went to try a new method of slowing the car to 9.25 for AFX index at Gateway in St Louis for the NDRL race next weekend. First trip to the lanes, light rain. So go back to the pits. T&T is called about an hour later. D/A is good due to temp. But grains, barometer, and headwind aren't great. Run a 9.07@145. Knocked about 2-3 mph off in the 1/4. Though the 1/8 mph was good at 119. Run #2 I pull the throttle back, 9.13@145. Same 60ft so going in the right direction. Run #3. Decide to leave higher 3400 vs 3000. It yanks the wheels hard and heads for the wall. Remembering the wall is 5 foot closer per lane I dump the throttle imediately. Back in the pits all looks fine. Run #4 go to the left lane just in case it goes right again. Hits hard an pulls the wheels quick. Heads for the centerline. I get it it reeled in on the 1/2 shift in the air as it 60fts on the rear tires. It's now right on the centerline. Another aborted run. Thought about added some weight to the nose. But decided to bring it home and make sure nothing is cracked, loose or bent on the chassis. It all looks good on the hoist. I'll scale it tommorow.
Doug

 

[493 Mike]

My wife told me this morning when I left. "You know what this weekend is?" Yes its the same weekend I've broken parts or had issues for 5 of my 13 seasons with this car. Water pump (though we fixed it and won). Pinhole in #6 intake port causing the engine to hydralock. Broken ball stud on the carb in the burnout box. Broken forward clutch carrier in the trans. Broken ring gear on the converter (brand new 8 runs). That brings us to today. Milan's renovations aren't complete. So I made the trip to Lapeer international. Never run this car there. The track is plenty long, well prepped, but the wals are 5 foot closer to the centerline. Went to try a new method of slowing the car to 9.25 for AFX index at Gateway in St Louis for the NDRL race next weekend. First trip to the lanes, light rain. So go back to the pits. T&T is called about an hour later. D/A is good due to temp. But grains, barometer, and headwind aren't great. Run a 9.07@145. Knocked about 2-3 mph off in the 1/4. Though the 1/8 mph was good at 119. Run #2 I pull the throttle back, 9.13@145. Same 60ft so going in the right direction. Run #3. Decide to leave higher 3400 vs 3000. It yanks the wheels hard and heads for the wall. Remembering the wall is 5 foot closer per lane I dump the throttle imediately. Back in the pits all looks fine. Run #4 go to the left lane just in case it goes right again. Hits hard an pulls the wheels quick. Heads for the centerline. I get it it reeled in on the 1/2 shift in the air as it 60fts on the rear tires. It's now right on the centerline. Another aborted run. Thought about added some weight to the nose. But decided to bring it home and make sure nothing is cracked, loose or bent on the chassis. It all looks good on the hoist. I'll scale it tommorow.
Doug

Maybe it's the season number?
Mike

 

[Budnicks]

I'm glad you didn't hit the 'closer walls' or go over into the other lane
there's always next week, I always kept telling myself that,
when **** didn't go as well as it should...

Good luck hopefully it's nothing too bad, maybe just an adjustment change

 

[Unkle Krusty]

From my days at the road race track, I decided, some days are better than others.
I know very little about launching something with power, and having it go straight. The bikes were controllable via the clutch.
Hope it goes better next weekend.

 

[dvw]

Got the scales out today. Add 210# in the driver seat, 200# for me, 10# for my suit, helmet and safety gear. A bit of an eye opener. Right rear is 100# heavier than the left. It should never go right at the launch. Raised the front by the center of the K frame until the tires were off the scales. Now the RR is 20# light. That uncovers the issue. When the front tires come off the ground all preload from the front is lost. Now with negative preload in the rear during a wheelie the car drives right. With all 4 tires back on the scales the right ladder bar preload is loosened. Each flat on the hex is counted, 8 flats. That number is way high. How did this all happen? Over the years the car has set high on the right, low on the left front. So what did I do? Cranked the LF torsion bar tighter. This also adds preload to the RR, until it wheelie. All shock adjusters are fully loosened to check for bind. Scale readings don't change. Time to start over fresh. The right ladder bar pivot bolt was removed to eliminate any rear suspension influence on the front suspension. The torsion bars were adjusted to level the front right to left. The bolts now are with-in 3/32" of being screwed in the same amount. Previously the left bolt was screwed in about 1/2" further. With the front sorted out the car measured at all 4 corners. The front and rear are both level side to side exactly. Now we move to the rear. Measuring the height of both rear springs the LR coil over platform is one revolution higher than the right. They are adjusted and equalised. Next set preload. With everything level and no preload the RR is light. By extending the adjust it raises the front of the right ladder bar. It only requires 2 flats to get the RR to 25# heavier than the LR. This will be a good starting point. Now the car only sets about 1/2" higher on the right than the left race ready with drivers weight and fuel. Amazingly the right to left weight bias is now 50/50. 54% on the nose. Much more confident about a 9 hour trip to the track now.
Doug

 

[peabodyracin]

I sure admire your attention to detail. I'm guilty of the TLAR approach the vast majority of the time. That Looks About Right. Hope it sorts out as you expect.