Monthly Archives: July 2008

Gas, Oil

VIDEO: Race 2 Beginning – Behind Pat

With a nice solid month to prepare for Pueblo after the La Junta race, I loaded up the ol’ orange car and headed down to Pueblo for our July double regional.

I headed out on Friday to do a bit of testing. I wanted to do some A->B->A tests with my dual
element wing. Plus, not having been to Pueblo since October of last year, I wanted to make sure there were no horrible imbalances or other oddities I had created with my various updates to the car.


I headed out first session with a set of Hoosiers from La Junta’s test day, figuring they would still have some reasonable life for basic shakedown testing. No such luck! The rears had gone off to greener pastures, so the car had heee-yuge oversteer everywhere on track. I was spending so much time keeping the back-end behind me, the best I could muster was a 1:36 lap. With respect to Dorsey Schroeder, this was “slow loose”!

So, I came in and put in one of my sets of Goodyears from John Berget, which were my tires from La Junta as well. Testing from La Junta had shown that the 160 Goodyears were clearly quicker than the R35 Hoosiers (perhaps not a fair comparison…), and that the 20×8 Goodyear front fits the Radical better than does the 20×7.5 Hoosier.

I ran several laps, and came in with a 1:32.5, about a second better than I had ever run before. Now that’s progress!

Interested in testing some aerodynamic effects, I removed the 2-element wing, and installed the Radical factory wing at maximum angle. The net result was a slight 1-2mph gain in straightaway speed, but the reduction in rear grip made it much harder to get around track, so I couldn’t match my 1:32 time.

I reinstalled the 2-element wing, and reduced the flap angle somewhat to get a bit of straight speed back. Happy with the balance, I removed the front dive planes to see what affect they have. Again, their cost was perhaps 1-2 mph of straightaway speed, but the new inability to hold nearly flat through 5-6 complex cost more time than the straight speed was worth. So, I put them back on, and had a nice car for Saturday.


Saturday was a hot day. Really hot. Damn hot. 108* hot.

Practice was largely uneventful, and I ran most of the session just enjoying myself, finding people to pass and play with. In the midst of all this seriousness, we tend to forget to have fun, right?

I threw on my newer set of Goodyears for Qualifying. Boy were they better! I ran a slightly shorter qualifying session to preserve the tires for Sunday, confident that my times would be good enough for pole position. As it turns out, I had a new best of 1:31.50, a solid two second improvement over my previous best. Not quite to the 1:29.xx I had hoped to beat the previous CSR record, but still quick nonetheless.

The only concern was that I started to notice the car stumbling out of 2 and 3, showing low fuel pressure on the dash. Problematic, since the car had 5+ gallons of gas in it during those times. I guess the higher speeds plus the longgggg Radical cell was allowing the pickup to starve, even with the collector in the fuel cell. Crud.

So, this made the race a bit of a problem – was I going to be able to get through without persistent starvation problems costing me the race? Worse, although normally better, they announced races would be 18 laps instead of the normal distance of 14 (?) or so, so now I had extra laps to contend with? Double crud.

So, my strategy was this: I warmed up the car in paddock, then shut it off and filled it absolutely to the top. I drove over to grid, and shut the car off until we were signalled to leave for the pace lap.

I did everything I could to preserve gas where I could. Kept the revs low on the pace lap, high gears etc. Gathered up the field as usual and….they waved off the start! OK, that’s fine, one less lap for me to do under green, right?

Well, not exactly. One of our new PSR drivers had gotten to grid late, and had made his way up through the field on the pace lap (BIG BIG NO NO) to take his grid spot. Seeing this, the start was cancelled. We were all black flagged, and sat for approximately 42 years on grid, in our hot race cars, in the sun, with no umbrella. It was hell.

Finally, after an interminable wait, we restarted, but the race distance had been reset to zero. Oh no! Already being worried about fuel consumption, now I had two fewer laps worth of fuel! Triple Crud!

So finally we got our green flag. I ran the first 3 laps completely flat-out to build up a gap. Joe was in my mirrors briefly but disappeared eventually. Grant was not a factor, and Pat was still breaking in his 2008 ‘busa, and taking it easy. Chris Waterman had a revs problem and was just cruising to get finishes. That left Paul, who quickly disappeared from my mirrors.

I spent the rest of the race short-shifting, around 8K RPM, coasting a bit at the end of straights like they say to do on TV (hah!), and using higher gears when possible. My biggest problem was the unbelivable heat – which I have never had a problem with before. I took the checker, although in my doggedness and heat-addled state, didn’t realize it. It was halfway around the last lap before a corner worker gave me the “chill-the-f-out” sign with his hands that I realized the race must be over.

I came in and got out of the car, feeling more than a bit unsteady. Wow. Not a very eventful race, but a nice flag-to-flag win, alright! Although I’d never seen him in my mirrors, Paul said he could just barely see me the whole race, and I always stayed a turn or so ahead of him. I was running to a 1:35 or so pace, so that was evidently enough.


Sunday was a little bit cooler than Saturday, thankfully. Again, I threw my old set of tires on and played around, since the car felt good, the air was cool, and durnit, I wanted to go play!

Qualifying was also relatively uneventful. I put my “Good” set of tires back on, and turned a few laps, again, coming in once I knew I had a pole time.

By our race, the cool morning had given way to an oppressively hot day. Once again around 105 air temp, and probably at least 140* or so on the tarmac.

The race was a much more ‘normal’ start. Paul started second place next to me. I did my usual slowish run up to the flag, to take advantage of the Hayabusa’s torque. The green flew, and both Paul and I got good starts. However, all was for nought, as Pat came ROCKETING by us by 2/3 down the straight. Holy Cow!!!

After this followed some of the most fun laps of my short racing career. Based on qualifying times, I was about 5 seconds a lap faster than Pat, a LOT! Pat has years of experience behind him, and knew precisely where I could and could not have a chance at passing him. He was battling a clearly evilly loose race car, sliding all over the place, and absolutely driving his heart out. Absolutely amazing stuff.

Twice I got by him leading into the straight, and he simply drove right back around. Holy cow! Paul said he even got by at one point, and he simply drove by both of us again. Lap after lap we were side-by-side, or nearly coming out of 2, 3, 4, 7, and 8, but always, he would just rocket away as soon as he got on the gas. Once I nearly had him into 9 but had to dodge a bit when he broke earlier than expected.

However, a few laps in – disaster! I was behind Pat trying to decide how to get by him and build a gap over the course of a lap such that he wouldn’t just immediately drive by again on the straight. So, I concluded I’d have to do something in 2, since he gapped me badly down the straight, but was very slow on the corners. He went slightly wide, and I ducked down inside again. However, the car immediately spun. I corrected, but the car lazily kept going around, and I spun off onto the inside between two and three. I saw Rob coming in the
Red PR6 and hit the brakes to avoid rolling into him. I got the car turned around, covered in dust, and got going again just behind Grant.

Now in catch-up mode, I chased Grant down HARD, and passed him a lap or so later. Off in the distance I saw Rob in the PR6, and set about trying to track him down. It actually happened a lot faster than I thought. Rob later said that he backed off, thinking I didn’t have time to catch him, but we were only 8-10 laps into a 18 lap race. I caught Rob into Turn 9, and was able to get away for a couple laps.

Before long, the temperatures started to take their toll however, and the tires disappeared. All of a sudden, I went from 1:33-1:35 laps to holding on for dear life running 1:38’s. I was having to brake and turn in OH so gently to keep the car behind me, oversteering everywhere. Turn 7 was a huge excercise in car control each time out. Turn 6 turned
into a drifting expedition.

With these sort of antics, it wasn’t long before Rob had caught back up, and we spent the rest of the race battling within 5-10 feet of eachother. He was clearly faster. However, I had also spent a number of laps behind Pat, learning where you can and can’t get by at Pueblo, so I knew where I could back off and give myself some time to breathe. Several times he got up next to me in 7, but I always kept the outside line and was able to be inside for Turn 8. About 4 laps from the finish, he had an excellent chance to get me downhill out of 4, but
Joe Weathers, having engine trouble, balked Rob and I was able to squeak by.

Finally, FINALLY, the checkered flew with Rob just inches behind me, and we congratulated eachother as we rolled down the straight.

In the end, it was an entire race of close, clean racing – what a tremendous race!


Again, I got out of the car hot as can be. This time I smelled a bit of fuel, and heard a hissing sound. long story short, a post-race inspection showed that the rear bulkhead had separated from the car, allowing header heat to radiate directly on the fuel cell. Not only did this melt the fuel cell, but that was why I was getting so bloomin’ hot
in the car!

Also, I ended up with a class win. Unbeknownst to me, Pat’s engine had exploded later in the same lap that I spun, and that pass of Rob ended up being for the class win.

As it turns out, it was due to the incredible amount of oil coming out from behind his car – note the pictures of my car. This ended up being educational in regards to airflow over the car, and around the two-element wing I had cobbled up for the car. Cool stuff!

Finally, it would seem that – perhaps obviously – Goodyear R160’s are no good on a 1200# Radical in 100+ degree heat. The fronts were blistered all around the inside edges, and the rears had about 1″ of cord all around the inside. Small wonder the car was as loose as it was. I guess I get to take away a small amount of pride for managing to hold on with such bad tires underneath me. Small victories…

Tire Tidbits

Cleaning off my desk today, and found some notes from a conversation with Richard at Rilltech, in regards to tires. He mentioned:

  • The 20×8 GY is slightly narrower than the 20×7.5 Hoosier (verified on their websites)
  • A good combination can be R35 on the outside tires, and R25 on the inner
  • Depending on your car’s balance, perhaps even R35 on the outside front, and R25 elsewhere

From what I can tell, the approximate order of compound is:

R25 < R160 < R35 < R270

But, who knows?