:. Racing .:. 2006/04/16 - RMSolo Summer 2006 #1
Dusting Off the Cobwebs
After a HUGE absence from autocrossing, I finally hopped back into the car for some RMSolo action to start the season. With Time Trials just a fond memory now, this is about all I get to do this season. Fine enough - the 300ZX will keep me amused between races, I am sure.
Fresh from my IMI day, I moved the bias towards the front to try and prevent the rear locking, but still did not get it right. The car was locking up the rears and wanting to spin all weekend, and led to a few spins. The shocks are back down to their normal -20 rear spot on rebound.
Handling-wise, steady state seemed reasonble, but as always, still too much understeer. Trying to power out of corners was impossible, as the car had a HORRIBLE power-on push. Tight corners felt quite bumpy - I am going to soften the gas pressures down from 150psi to 100 or so, to see if that will help.
The 400/600 setup is getting that situation that R. Pare told me about - steady state understeer that turns into corner-exit oversteer, because the tires have been in an understeer state the whole corner, and then bite as slip angle reduces. I will try either raising the car, or increasing rear springrate to see if that neutralizes the mid-corner somewhat, and hopefully eliminates that corner-exit snap before the push starts in.
The gearing is still too high, it seems. Would be nice to get a 14T sprocket for the front of the car.
Splitter rubbing is present, but minimal, so I am going to leave the front ride height where it is for now. With any kind of reasonable rear ride height, that should be acceptable.
Points were poor - 909. Part of that attributable to poor setup, some to driver confidence because of the turn-in instability, and some due to old tires.
For next time: Soften gas pressures, lower the front 1/8" or so, try increasing front preload, test removing the swaybars, try adding some rear bump to fix Corner-exit understeer.