Sandia Race Report 8/10 – 8/12

This past weekend (8/10-8/12) Tyler and I made the six hour trek from Mesa to Albuquerque to run at Sandia Motorsports Park.

We had just pulled out of Mesa and travelled about four miles on the Beeline Highway when something prompted me to ask Tyler if he had his driving boots packed.  He checked and he did not.  We turned around sprinted the twelve miles back home.  That little side trip would cost me a little bit because the combined 24 mile detour left us 2.6 miles short of a Gas Station in Payson! 

Fortunately we were hauling race karts and gear in the trailer.  Coasted to a stop on the side of the road, opened the trailer and poured in two gallons of mixed race gas into the tank. With 110 octane unleaded race gas costing $7 a gallon and a bottle of the castor (two bottles to five gallons) we mix with the gas also costing $7 each the per gallon cost of fuel to get us off the highway was almost $20!  In case we had this same issue further on in the trip I took the opportunity to fill one of our gas jugs with 5 gallons of the “cheaper” premium pump gas.

Since it was going to be a long weekend we stopped in Holbrook for the night before pushing on to Albuquerque the next morning to run test sessions that afternoon.

The Club at Sandia that was organizing the event had never had karts run with them so they decided to have us run the shorter track layout.

The Sandia track seems to have started life as a small banked oval track they had grew some lop-sided Mickey Mouse ears at each end.  This means that the front and back straights of the oval serve to connect the two ends of the road course.  Because of the banking of the oval you literally jump into and out of the oval across those transitions.

Running the short version of the track meant that once the drivers jumped into the oval on the back straight they would continue around the oval back to the front straight and then jump out the other side.  Taking this shorter route the 125 shifter karts were “only” doing 87-88 mph when they left the track surface (just before the braking zone).  If they had run the full course and jumped into and out of the oval on the front straight they would have been doing at least 100 mph leaving the oval.  Considerably more stopping power and time required to get around turn one onto the road course with very little run off room on the outside.

The data trace for this section of track is kind of interesting.  Just before the “jump” out of the oval Tyler hits 90 mph (at 54.484 seconds into the lap).  2 tenths of a second (54.607) later the data shows he is doing 99.2 mph and a hundredth of a second after that (54.698) he is back to 88.7 mph.  You can certainly see that the kart is airborne for that fraction of a scond.  Two and a half seconds after that he has braked down to 68.5 mph to enter Turn 1.

The data acquisition on the kart showed that Tyler was hitting a good 2 G’s going through the banked Turn 1 of the road course and a 5 second sustained 1.5 G load going through the banked portion of the oval.

As the weekend progressed Tyler started to experiment with different approaches to the very fast Turn 1 and was soon driving it very differently then anyone else.  Most were taking a classic stay wide and late apex the corner. Tyler on the other hand looked like he was giving a quick hard stab to the brake and downshifting just before the corner.  This would upset the rear end of the kart and allowed him to rotate it through the corner and be back on the gas accelerating before the apex.  The sound difference was pretty amazing.  He was on the gas a full 20-30 feet before the other shifters were.  The data showed that by the time he was hitting the highest G load into that corner (7 tenths of a second later) he had already accelerated to 72.8 mph which is 4 mph faster.

Watching him I was thinking that this was going to kill the tires as the track surface was pretty abrasive.  I could not see his line on most of the track so I don’t know what he was doing there but whatever it was he was actually conserving the tires.  I checked the tire temps of the other karts around us after the sessions and whereas their front and left rear tires were in the 130 degree range their right rear tires were in the 150’s.  Tyler on the other hand consistently came in with all four tires in the 130’s.

He did the four test sessions on Friday and the first practice on Saturday with the tires that were on the kart (for a total of seven heat cycles) before we put new tires on to finish out the weekend  (five sessions) and he was not complaining of a lack of grip.

For the race on Saturday Tyler had qualified third in the 125 shifters (this would be only his third race in this class) and he despite making a horrible start that saw him fall down the grid to sixth place by Turn 1 he managed to claw his way back up and finish the race in third.  In doing so he had some great close wheel-to-wheel racing with William Herr and Mike Laycook.

For Sunday’s race we changed the gears to run the same ratio that the 1st, 2nd and 4th placed karts were running and Tyler qualified in second position.  This time he did not muck up the start.  However, on the exit of Turn 1 he did not give enough “racing room” to the kart on the outside in Pole position and forced that kart to the dirt on the outside.  Fortunately that driver kept control and got it back on track after losing a few places.

Karmic damage was done however and while Tyler did manage to take the lead and hold it for five laps he eventually lost the lead and trying to either make a low percentage move on the new leader or just trying a different line he hooked the left rear wheel off the track in a tight left hand corner and spun off.  A kindly corner worker gave him a push and got him going again at least two laps down.  However that Bad Karma was not through with him yet.  Two laps later as he was coming through the tight banked right hand Turn 6 the left rear wheel sheared the studs off the hub (probably due to damage from the previous incident) and sent the tire bouncing across the in-field.  Tyler managed to drive the now three-wheeled kart back to the pits.

I think he got in enough laps for a finish so we will come away from that race with some points at least.