A big upside of the testing being so early in the morning is that we’re done by 9am and there’s a whole day to try and work on any issues that came up during the test. Yesterday’s work involved calling 6 different auto parts stores and driving to 3 of them to get the various bits we needed to troubleshoot the problems. The result – yes indeed there was a fueling problem. A fitting inside the fuel cell, between the pump and filler plate, had come off enough to bleed off most but not all of the fuel pressure. The problem cleverly combined itself with the overheating incident to try and make it look like something else. And now we have a spare good fuel filter.
The weather cooperated beautifully during the day but towards the afternoon a few rolls of thunder (followed by an incredibly close lightning strike, must have been within 1,000 feet of where we are) announced that cooperation was about to end. Fortunately we were now done, just refilling the fuel tank (yes in a lightning storm – what’s the worst that could happen, right?) and bolting back on the pieces that were removed to get to things.
With the tarp on the car for the night we relax for a bit, walk around Manitou Springs, then call it an early night at 8pm and pass out.
Morning brings clear skies. Today we test on the upper section. We learn that there is ice across the road in the W’s so that’s as high as we’re going to go. On the upside there will be more runs. The start is now at higher elevation and it’s noticeably colder. The pits are in a rutted dirt lot but the D2’s suspension handles it easily. I actually enjoy watching it articulate over the ruts. We set up as the sky is getting progressively lighter.
Since it’s dry we decide to keep running on the Hoosier A7s, although we will most likely have to switch to the wets after a few runs due to wear on the rears. The sun peeks up above the jagged horizon. We line up and the first three runs Jonathan gets progressively quicker, getting down to 2:20. For the fourth run we switch to the wets and at the initial pressures we set they are not working well. Jonathan is a full 8 seconds slower on these tires and informs me they don’t inspire the needed confidence. Still, after four runs his earlier 2:20 time is the fastest anyone has gone so far.
We drop the pressures a few psi and the 5th run is 4 seconds faster, followed by a 6th that is at 2:21. Jonathan is now much happier with the tires – the pressure changes combined with a bit of break-in have made a big difference. He goes out for the 7th run and we soon get notice that he pulled off with coolant leaking. Sounds like another belt is done. This is confirmed when he coasts down. On the regular LS3 powered D2s I came up with a belt guard that prevents the belt from coming off the non-flanged waterpump pulley. Our best guess is that the rapid RPM changes in our application cause the belt to try and rapidly accelerate and decelerate the alternator, which may create temporary slack that the tensioner can’t keep up with. The fix seems to work well, unfortunately there’s no room for it on the LSA motor due to supercharger belting. There are a couple different avenues we can pursue and we are currently leaning towards an electric waterpump. Others are adding a flange to waterpump pulley and/or an extra flanged idler to the system.
This is why we test. We learned a huge amount from this trip and there are still three weeks before the race in which to react and improve. Paul again went a few seconds faster in the later runs so we are second fastest again, but that’s not bad and we know that both our car and driver have more to give. Just have to take care of the details. Based on what we’ve seen my goal of 9:20 is achievable if all goes well. We’re on more or less even pace with Paul Dallenbach which is gratifying. Paul’s car is a beast:
We took a lot of video but honestly I’m not up to editing and posting it right now. It does look cool. The oddest thing is that between the super-quiet exhaust and the whine of the straight-cut gearbox, the D2 sounds like an electric. No joke, I’m going to have to put a note on the video that it is NOT an electric vehicle. And speaking of electrics, the Honda factory electric car is a fun machine. They obviously spent a lot of effort on aero and are claiming 1,000 hp. Maybe they were holding back in early testing but their times were a ways behind ours.
Now all that’s left for us here is wait for the trailer axle, transport it to Wyoming and hopefully get all the way back home where a flurry of activity awaits. Tristan took a flight from Denver to get a head start on it, Jay and Peter will travel back with M and I.
As a quick touristy thing we walked over to the Cog Railway and took a ride up the Mountain. Today the train didn’t go all the way to the top due to 60mph wind piling 6 feet of snow on the tracks. The race is only three weeks away, what will the Mountain have in store for us then?
