I tried something a bit funky on my xray this weekend that smoothed out a handling problem I was having.
On corner entry (transition to power off) I'd get an inconsistent oversteer. My car was *very* sensitive to smooth driving and small changes in droop. The car would behave differently in the 1st part of the race to the second. I use very little traction sauce so it wan't that burning off. I also run 1/12th and can run a respectable, clean 8 minute race - though not with the good guys - so I know how to drive smooth.
Any rate - I made 2 changes to my car that made it much smoother on corner entry.
- shifted one set of cells (left side of the saddle pack) one slot forward to move more mass up to the front. This reduces the amount of weight transfer to the front tires on corner entry.
- a little drill press and grinding work to allow for a "kick-down" on the front lower arm. Essentially I drilled a hole to move the rear suspension holder on the front bulkheads up a bit. So the front bulkheads look like the rear where you have two holes for front and two for rear holders. I changed caster blocks to 6* so I have an effective 3* caster. The steering belcrank needed a little work as well to make it clear the suspension holder.
What this does is make the suspension want to extend under power off and want to compress on power on. This reduces the mass transfer on corner entry and on corner exit. Saw some Losi guys doing this for this reason. (a pushy car on exit doesn't bother me a bit. I try to apex late anyway so I don't make lots of steering inputs late in the corner.)
I did both at the same time and didn't try it with only one at a time - so I can't tell you which one did more. perhaps next weekend I'll move the battery back to see.
My car was much smoother on entry, which allowed more mid corner speed and exit speed. It had a very slight push - so I sauced the full front rather than 1/2 front. I also drove more aggresively. Grabbed it by the scruff and tossed it around more.
Once the car took a set in the corner, it dug in very hard and could carry lots of speed and still rotate fast and smoothly. never came close to traction rolling enven though I was pushing the carpet around and making it bunch up a bit.
My other suspension setting are pretty standard for long arms, though I do run the hardest front springs (38lbs?) and then 28lbs on the rear. 60 wt front oil, all closed and 50 wt. 2 closed rear. Longest wheel base and 2* rear toe, 0-1* front toe out.
My personal best before this was an inconsistent 25-5.04, today I ran a 27-5.03 (not sure about the time) for 2nd in the main.
Best race I've seen at our track to date. 3 of us on the lead lap and the slowest not less than 24 or 25 laps ( I think...)
Would of had 28 laps but I was stupid and allowed myself to get close to a back marker - making an inside pass and he chopped me into a pipe, cost me a 5 second marshall.
( the next lap, I came up behind him again. He crashed in front of me, I passed him then he jumped a pipe to get back in front of me
he blew a corner wide after a bit and I finally got passed the kid on the inside