:. Racing .:. 2005/06/18 - Autocross
Results: Here
"The Front just feels....weird"
After a solid 3 weeks of not really playing with the car to avoid a bit of a burn-out feeling, (not to mention the hellacious process of buying a house), today was the first race since the carb-flooding event at PPIR on May28. It was fun to get the ol' girl out again and have some fun racing around!
All I did between last event and this was stripping the carbs and reassembling them, to assure myself that there were no fundamentally flawed parts in the Keihins. They are, as it turns out, quite simple. At any rate, nothing seemed wrong, and I'm waiting on some parts for the Mikuni carbs, as Hasty suggests I try, so back on the car they went. Bummer. They did their flood trick once today, for which I have no explanation. I'll try the Mikunis and see if the problem persists or goes away.
Today was the first day I had a co-driver with any DSR familiarity. Steve Ott and I finally managed to get in touch with eachother, so he co-drove the Radical today to see if he could give me a hand with getting this car tuned a little bit (not to mention getting to drive a fun car around a little bit - heh). His basic impressions were the same as mine, in that the car doesn't turn in for squatsky, and has a real lack of front-end grip overall. They way registration worked out, he ran first in X-class, and I followed in the 2nd heat running B-Mod.
During Steve's runs, first we added some front bump, as well as 1/32 of toe per front wheel, which he said helped some. Then added 5 flats on rebound, which was a bit better, and then a further 5 flats. Turn-in was finally deemed acceptable. Turn-in was definitely much better - back to where I'd remembered it, but with the shocks now turned up quite high on some pretty soft front springs, there seemed to be a real mismatch between the feel on turn in (very, quick, light), and the time/amount of roll the car had once it took a set and stopped transitioning. It was a very strange feel - stiff/soft/stiff/soft as it would transition, and move on and off of the shocks. Steve's last commentw as "It just feels...weird. I dunno...I'll have to think about it." My thoughts exactly - weird.
As a result, it was a very strange car to drive. While it would turn in, the car felt like it would roll and wallow a little bit after the initial "point", and so feel-wise, it was very strange. It took a long *time* to roll, almost. I think the answer is to back off on the rebound a bit, and bump up on the front spring, at least to get the front-end feeling a bit better, especially in slaloming.
One other change that was interesting was adding a bit of rake to the car. This made quite a difference, and seemed to take care of a fair amount of understeer. This might have been masked just because of the goofy feel of the front-end, but the push didn't seem as bad as normal. I'll try raising the rear even more, and if gets out of hand, bump up on springrate and seeing if that allows me to get the rear of the car back down to within a normal range of the front.
Another consequence of the higher bump/rebound in front was a resurgence of the noncompliance over bumps on the northwest part of the lot, so I think either the bump or the rebound does need to come back down. Especially, I only noticed it at the front of the car, where we had done all of our adjusting. So, very clearly, the shocks are the issue when it comes to bump compliance on the lots. Imagine that!
It was a very drama filled day - on Steve's second run, the RR toe link broke (second time), which means that clearly the threaded rod in there the first time (that I replaced the first one with) is *NOT* what is supposed to be in there. I'll see if I can find out the proper toelink replacement, and get *four* of those for future use. Seeing the car come in with the RR wheel at 45* to straight was an interesting experience...
In other misc notes, Steve commented that it felt like the brakes didn't have a lot feel, and seemed like kinda on/off. His experience was that Hawks tend to be a little like that, and they use Porterfields road racing. I've also felt like getting used to the brakes has been quite difficult, so perhaps there'd be some merit in looking at some alternate pads to replace the Hawk Blues with next time around.
Overall, the results were pretty good. 945 points and a 21/221 finish, on a day when I was just trying to judge car feel a bit. Certainly since I wasn't competing with anybody, I did have plenty of fun driving, despite the very quirky feel of the car.
Plan for next time: Back to at least a 300# spring up front to see how that will affect the car's ability to transition properly. Rembering how quickly the 'vette was able to transition with its new front spring, I think that will help in slaloms. The key will be trying to maintain and/or improve the balance, and then avoid having the car feel "skittish" (which it does not feel now).
As the car still has a push, this might necessitate bumping the rear springrate to 400# to keep the same basic balance the car has now. Also, I think I'll drop the shocks back down a bit on both bump and rebound since they seem to be too stiff for the time being. Steve said he'll talk with some Radical guys at June Sprints to see if there is any good info out there to be had. I'm hitting the books to see if I can put data to what I was feeling.
Lastly, it's looking like this set of tires has finally had it, so I'll be wanting to get a new set of R25A's here soon - maybe I can try some 20x7.5 fronts and see how that improves the situation. Or, perhaps staying with 20x7.0's would be more intelligent for comparison's purposes? Always more development!
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