Wednesday, July 21, 2010

Moving Up in the Pack

Sorry folks, wrote this several months ago but forgot to publish it... I am now due for a season wrap up (which will contain tales of the season points race, car modifications, weather factors and lessons learned). I'll let this entertain you while I put that together :) If you want a sneak peak of that, you can of course check out my graphs...

The latest SCCA event on 7/18 was yet another high water mark. Even though I didn't beat either the Turbo Miata or the CRX, I was close enough to make it look possible this time. Everyone in the class ran well, and the stats speak for themselves. I was over the 60th percentile in the PAX standings, a full 12% higher than ever before. If one uses the Super Stock PAX that is more appropriate for the actual level of modifications to my car, I broke into the 70th percentile. As a SS car, I would have out PAXed everyone in SSM. Relative to Russ, my raw time was only 4.3% slower, and he was 15th in PAX standings overall, just shy of the 90th percentile.

The day started and ended well. The first run had me in second place in SSM with Brian only 0.7 sec faster. The next couple runs got away from me a bit (one had a spin) and predictably the other competitors moved up and passed me. In the afternoon I had one spin to start, then a run that shaved 0.3 sec off my best. This left me in position to give it my all. I just concentrated on driving it all harder and closer to the edge, and somehow didn't loose control. The result? I shaved a whopping 1.7 seconds off my time. I was still in 4th, but up with the pack instead of trailing.

The conclusion? I had plateaued again. My improvements in my ability to control the car had allowed me to get comfortable again. Need to push out of my comfort zone. I did a fair job of this in the second half of the next event too. I finished with the 24th best raw time (up from 29th after the morning runs) at the 7/31 Renegade Miata event. There were over 60 people at that event, but this is not directly comparable, of course there are about 25 miata of all levels of prep, and basically all the cars have fenders (no formula cars or carts). But there are definately lots of well prepared cars there, so the conversion is entirely unclear being in the front half of the pack is good.

Oh, and then there's the mods I just did... (next post) :)

Friday, July 9, 2010

Midseason Summary

Ok so I've been a bit delinquent. But given that I have an official follower and a couple people have admitted to lurking here, I should possibly resume posting. The last post was about cold weather and tires. The good news is that my tires were undamaged. Now the season is half over, so lets go for a summary.

I did the NER school and the Evo School this year, both were very helpful. One of the most helpful bits was learning about trail breaking from Grant R . at the NER school. Secondly, I felt a bit better after the EVO school in that the second day in the Challenge school, I was mostly able to hang with people who were far more experienced. It was clear however that I had some consistency issues. My instructor however is a national level competitor in my class and she did say that my car seemed to have potential to be competitive with proper driving and modifications.

Competition wise, We've now had 4 SCCA events and my results are:
  • 4th of 5 on 4/11/2010 (47% SS pax)
  • 4th of 6 on 4/25/2010 (47% SS pax)
  • 3rd of 3 on 5/2/2010 (64% SS pax)
  • 2nd of 5 on 6/6/2010 (46% SS pax) - Trophy
So I'm solidly in the middle of the pack when one uses a pax that is reasonable for the actual level of preparation for my car. The 64% pax is an anomaly probably due to the fact the event was at New Hampshire Motor Speedway, and drew a different crowd. The 2nd place finish in the last event is facilitated by the fact that the Blue CRX sheared an axle the day before and Brian was competing in an RX-8 he never drove before. He made it close and forced me to have a good last run which shows that he's really quite a good driver.

In other entertainment, I've been daydreaming about working the car into a state where it could be competitive. Right now, it's simply outgunned by the 340hp 8lbs/hp CRX with the 275 front tires and full suspension etc. I don't have to go crazy to become competitive, but for fun I started a thread on the SCCA forums about the ballast rules for my class and how they make it ridiculously hard to apply forced induction without bumping up to XP class. The resulting thread basically convinced me that it might be fun to try to build up a lightweight contender instead.

I certainly don't have the money right now, but I may have some fun phantom building it on paper, and figuring out what order to do stuff in to move that direction. There are some basic things that need to be done before one even thinks about working over the engine/transmission and changing the wheels as mentioned in that thread. More speed can be gained for less expense, but it would be kinda fun to know how many $$ I am from the dream lightweight normally aspirated lotus SSM Autocross setup.

I'll post some thoughts on my upgrade path a future post.

Friday, March 19, 2010

Yokohama A048 & cold weather

Recently I've been dealing with a relatively technical issue surrounding my street tires, and their temperature requirements. Last spring when I deemed the factory original Yokohama AD07 tires to be nigh unto bald, and definitely unsafe in wet weather, I decided to replace them. A number of factors played into my decision. I definitely wanted to have a high performance tire, anything else seems a travesty on a lotus. I also was still thinking that I might still do some track days at NHIS and wanted something that would perform well there. I also wanted something that had at least minimal tread since I definitely planned to take it out on the road, not just racing.

In the end I decided to go with the "other stock tire." My vehicle has the lotus factory sport springs and dampers, installed after delivery, so the wheels and tires were not from the sport pack. The sport pack comes with a higher performance Yokohama A048 tire, which is basically a race compound tire setup with enough tread and durability to survive on the street. They definitely were not the cheapest option, but clearly would support me in a high performance driving situation. Basically, the decision was to run A048's on the street/track days, finish out the Kumho V710's and then buy Hoosier A6 tires for Autocross.

Through the summer I had no complaints. I never did go back to NHMS for a track day, but none the less had no regrets. The A048's give good grip on the road and their wide block tread gives the car an exotic look. One of the things I discovered upon purchase was that there was a sticker on the tire that warned "do not operate or store below 14 degrees F." That was a bit of a shock, but I have no plans to let the car out where it could get salt coated, or suffer an ice-induced skid. The latter was the fate of my Father's 1969 Lotus Elan. The elan traveled with the family for over 30 years in an state where it was always "going to be repaired" but never quite got there. I never saw it move except when pushed. I've promised myself that I won't repeat that mistake. I might make another, but driving my Lotus in ice and snow I will do my best to avoid.

The this past fall the Lotus was involved in a minor accident. Nothing serious, not even the hint of a possibility of anything other than cosmetic damage, but repair required removal and repainting. The removal uncovered additional cracking in the fiberglass, and eventually what I had anticipated to be a patch fill and paint turned out to be an entire clam replacement (covered in full by insurance thankfully. Hooray for Safety Insurance and my agents at Eastern Insurance!). None of this particularly bothered me since I had taken the car for repair with the intent of putting it directly in storage for the winter thereafter.

The problem however arises from the storage requirements for the tires. I had expected to have the car back in time to switch to the old stock tires, which I retained on the stock rims to be my "storage tires." The auto-body shop claimed they kept the car indoors all winter, and I believe them, but I saw the building when I went to check on it, and it appears to be unheated. I gave them my "storage tires" but I didn't think of it until after there were several single digit lows in our area this winter, so now I don't know how cold my tires got. To make matters worse when I looked over the tires, they seemed to have small horizontal marks on the flat rolling surface of the tread that might be cracks that I had heard referenced (but not described in any way) on the internet.

Since replacing the tires is a thosand dollar prospect, I spent hours trolling the Lotustalk forums, and the internet in general and found very little information on how to know IF your tires were suffering the effects of being over-chilled. I finally did what I should have from the start, and called the manufacturer. They referred me to Track Side Performance, I left a message, and one of their folks called me back. Here's what I learned:

If the tires have gotten too cold and cracking does occur it will be cracking in the side-wall/shoulder. Usually the tread face will not show a problem. The cracking will generally show up in the first few miles of driving the car, so the issue may not be visible until the tires are driven. He listed several things that are clearly cause for concern:
  • Any cracking that appears to expose lower layers of the tire
  • Any cracking over a half inch long
  • Any cracking in the inner side-wall or near the bead
  • Any cracking that runs along the circumference of the tire. This type of cracking changes the way the tire flexes, will get worse with time and can lead to failure.
If cracks are small and only running vertically the tires may still be OK. You can contact them and sent them pictures if there is doubt, and it is definitely not in any way guaranteed whatever you happen to deem as a small crack is at all safe. However, one thing he did point out is that marks on the flat tread surface that I was seeing are unlikely to be related to this problem, and some shops use dollies to move cars around and those sometimes create small marks running across the tread. Please Please Please remember this information is not to be considered authoritative, but based on a single phone conversation, and if you have any doubts get a professional involved. The fact that the crack is less than 1/2 inch and in the shoulder of the tire does not mean it's safe, it means that it might or might not be unsafe. In other words, if you have big or badly placed cracks don't waste your time investigating further, junk the tires. If they are small, and in the shoulder it might be worth further investigation.

We also discussed the changes to the tire rubber when it gets cold, and he said that getting the tire really cold had a similar effect as getting it really hot (heat cycling), both tend to harden the rubber, and permanently reduce grip. That's nicely consistent with the description of cracking that shows up after a little driving has flexed the cold-hardened rubber, so his descriptions seem to be internally consistent and I feel like I probably have found trustworthy advice at last.

So what's the verdict? Well, the marks I saw examining the tires in my basement probably aren't the problem so THAT is good. But I need to put on the A048's take them for a (SHORT!) drive and see if the cracking appears. I'll do that tomorrow...

Saturday, February 27, 2010

Wrap up and Rev Up

So somewhere around the middle of the summer my life got busy :). I didn't really maintain this blog for the latter third of the season. Oh well... Blogger claims I don't have followers anyway. So what happened in the second half of the season? Well, right after the last post I ran in an event with the BMW car club, and got a result that seems to be my best of the season... Then things sorta drifted down hill from there. The next SCCA event was Dry and fun and felt good, but my times slipped just a little. I think this is not so much of a difference in my skill as a difference in the courses. The BMW course had LOTS of slaloms and that's probably my best element.

Then there came the second half of the summer... Events went from one every 1-3 weeks to one every month or more. Add in the addition of a new romantic interest starting in July, and I didn't really put time into finding alternate non SCCA events. So the first issue is that my seat time went down. Secondly, I made changes to the car... New Tires. Starting in September I ran Hooseier A6 tires. My Kumho V710's had well over 100 runs on them, plus whatever the previous owner had put on them. I'm sure they were cooked, but probably it would have been better in the short term to go for a new set of V710's, but the general wisdom seems to be that the A6's are the tire to have.

But what's past is past. This season I look forward to

  • A repaired front and rear clam with now pristine body work and faster paint

  • Carefully taping my car to prevent cone marks like I should have done last year.

  • Analyzing my runs with MaxQData's Quantum

  • Getting an Alignment that is more autocross focused.

  • Working out the pressures for my Hoosiers

  • Perhaps a front splitter to add downforce and protection from cones

  • Perhaps the adjustable front sway bar from BlackWatchRacing

  • Definately working hard to make sure I get on the gas early coming out of turns!! (I suspect that I still wait until I'm almost done turning to gas it at least some of the time...)

Oh yeah, and I need to figure out which events to run!

The big question is to NEDIV or not to NEDIV. I'm leaning towards not given the distance, Decal Requirements and my generally busy schedule, but part of me really really wants to too :).

Disclaimer: The calendar below is UNOFFICIAL! I'm using it for myself, but you should rely on the website of the organization running the event for the final word on when/where events will be. As of this posting both the SCCA schedule and the BMWCCA schedule are not final either and might change