Slow Car Fast
June 12, 2012 - Another steering tweak.
The steering feels overassisted - it's too light for my taste. I have a few things to learn about power steering systems in terms of the results of different pressure versus different flow, but the RX7 crowd seem to think that trimming the relief spring should drop the pressure a bit. Others claim that the only real solution is a Turn One pump for $240.
The spring cut makes logical sense to me - and if it doesn't work out and I end up going for the Turn One setup, it doesn't make any difference. So I made the cut. A fairly conservative one at that. It's not a massive change, but there is a bit more meat to the wheel. I might try one more little snip later, but first I'll drive it for a bit to get used to the new rack and assist.
entry 647 - tags: steering
January 5, 2014 - The MG's seen some action.
First, I took it to the track again. I finally got the chance to see how it handled at the limit without the big fireballs. The answer? Not that well, really. The car was oversteering badly, feeling like an arrow flying backwards. On the sweeper, it was actively trying to kill me constantly. The steering still had the wobble in it I didn't want. I tried adjusting the rear suspension pickup points (based on something I came across in Mark Donohue's "Unfair Advantage", of all things) and it helped a bit. But it was still twitchy and difficult to even drive on the interstate without the car exhibiting roll steer.
But I noticed something. The front tires were worn as if I had significant toe in. Lots and lots of it. So I checked, and sure enough. The toe was way out. I fixed that and all of a sudden the car was much better. The odd roll behavior went away and the steering dead spot disappeared. All of that chasing around, and it was just a bad alignment. Which is odd, given that it's been aligned before...
I also took the car out to a Corvette autocross, which they found fairly entertaining. Unfortunately, I simply didn't have enough tire to deal with the torque of the engine on a first-gear course and finished 4th overall if memory serves. Still, it was a fun day.
So it's mostly a driver right now. There are still some things that need to be sorted - in particular a vibration from the transmission leaning up against the tunnel under load and the bad reverse selection - but those don't stop me from driving it. That steering problem really took the fun out of it. That's been sorted!
entry 648 - tags: track, steering, handling, autocross