In late 2023, we said, “Let’s be ready for Speedweek ’24”
- Improvements: We abandoned the fancy split-collar axle sprocket mounts and cut a keyway in the solid front axle instead, changed from a set of independent GoPros to a simpler 4-camera setup, made the steering wheel removable, and did some tiny tuning to avoid loading up during our long warm-up idling
- Maintenance: Pickle got some body ‘freshening’ and paint, a new ECU Battery, an automatic thermo-switch, and some new brake lines
- Safety: belts, helmets, fire extinguishers, clothing… all items are up-to-date and certified
- Schedule: Our list was down to the ‘nice to haves’ by four weeks out — probably a record for our deadline performance
This Is The (Speed)Week That Was
It was so very, very, very hot. 110+ hot. Other teams’ engines–that had never been troublesome before–were melting during their runs. We were melting ourselves; the staging lines were desert-caravan long. A partial cause of the long lines was that recent years had seen bad salt conditions, so this year brought out all the pent-up racers.
Sat Aug 3 – At 3:10pm, there were still 55 vehicles in line for the short course. We did not join the queue that day, and instead went looking for lodging. Wendover was FULL. Found a hotel in Wells, and made the 60 mile transit that night and the following morning.
Sun Aug 4 – Final prep, got in line. The short course was cursed with Instagram influencers, 50mph mopeds, rookies, and folks whose cars and/or drivers weren’t yet qualified for the long course. It moved at the speed of a glacier. We waited about 5 hours, didn’t reach the starting line, and parked on the side of the lane in a queue for the following morning.
Mon Aug 5 – Next morning, after the Record Runs, we got our first run at 8:58am. Only three miles on the short course, and we ran 178mph in Mile 3, but missed the 175mph “in the quarter” which could have promoted us the to the long course. Questions about the car’s performance and checking the chain took the rest of the day. We planned to get in line early for Tuesday.
Tue Aug 6 – Made a run at 12:24pm, and qualified for a record (back-up) run with a 192mph in Mile 3. Okay! That’d be more than 12mph over the record if we could back it up. We took the record-run-same-day-at-4pm option – but when we reached the head of the line, the car would not start. We pushed it off, and the Hayabusa roared … for a second or two, then Pickle coasted off the course before the first quarter-mile marker.
Back in the pits, we started diagnosis, but turned up nothing conclusive. Review of data later that evening showed a curious trace on the VBAT value, which suggested that the Pectel was powered-on continuously — but the injectors and coils were not.
Wed Aug 7 – We hit the salt early to correct the non-starting. We found a broken wire, probably caused the previous afternoon in impound, as we were draining the intercooler. The long (nightmare-long) waits in the staging lanes, made more hellish by the heat, convinced us to switch drivers and we moved to the long course.
The long course is run by both fast cars (less time on course) and by experienced teams (less time spent at the starting line). It moved more quickly than the short course line, and we made a run at 13:26pm. Over 190mph in both Mile 3 & Mile 4, hellya; but later we were disqualified and kicked out of Impound for a procedural error during the run.
In the pits, we found a split CV boot and … we were hearing some CV Joint noises. It’s probably worth saying that the drive chain, so far, was looking very good after every run.
Thu Aug 8 – Some shrinkage of the staging lines. On the long course, we made a run at 10:03am, and again qualified for a back-up (record) run by going over 194mph in Mile 3 and Mile 4.
We took the record-run-the-same-day-at-4pm option, and pushed off the starting line at 16:47pm. But Pickle broke the chain almost immediately off the line, and again we failed to “back up the qualifier”.
In the pits, we found a tooth broken off the primary sprocket. That’s new; the primary sprocket is hardened steel, and has never caused a problem before. But our best guess is that the loose tooth got lodged in the next sprocket valley and that popped the chain. We had no spare primary sprocket, and we had a bit of damage to the clutch pushrod, so our week was finished.
Our score was 3/6: three times in Impound, but three failures to complete the backup run. 🙁
We were encouraged that we had multiple runs over 190mph, but still troubled by the chain, CV joints, and the boost control system. We found the boost knob at 26 clicks out from minimum, while our spec said it should be 10 clicks out: how…?. Our MAP sensor recordings showed good peaks in the lower gears, but when Pickle settled in for a long pull, the graph came down then looked like it was ‘fluttering’ in a narrow range. We surmised the fluttering was the action of the wastegate… but why the boost control system allows larger peaks earlier is a head-scratcher.
Pickle went into the trailer and we drove home.
Just In Case We’re Going To World Finals
Though our SpeedWeek performance was not satisfying, the Salt was pretty good. We started watching the weather for the late September/early October meet “World Finals”. What must we do to improve our chances in the few weeks we have?
- More attention and more spares paid to our chains and sprockets; talk of changing them every two runs?
- Got a stack of new-to-us CV joints, and assembled both axles with good joints, new boots, and new grease
- We disassembled the wastegate and manual boost controller, looking for answers on the inconsistent boost.
- In the garage, we fixed a host of boost leaks, including a MAP sensor that had cracked its cover and failed
- In a remarkable flurry of speed-fabrication, we built “hub adapters” for the ’59 SAAB to connect it to a modern dyno
- The dyno showed that a prime cause of boost unpredictability was our “bleed type” manual boost controller. It also showed that the Hayabusa motor could still produce serious power. We fitted a dead-simple manual boost controller and dialed in a ‘safe’ level
- The tuner on-site at the dyno opined that our on-power fueling might be way too rich, and costing some power… but we deferred further tuning for a future day.
World Finals ’24
Surprising even ourselves, we were ready again, with no known issues. We expected to make a couple of 190mph runs right off the bat.
Sat – Made a run at 5pm, barely over 180mph. We qualified, but what happened to the 195s? Our RK chain looked like raw bread dough. We got no logging out of the Pectel (probably from tutor error during a previous “let’s write new log settings” session), but the databox has its own MAP, and that MAP sensor says boost is low so we gave the manual boost controller 2 1/2 turns toward the positive. And fitted a new chain, naturally.
Sun – What do you know? The car (which is the current and previous record holder in BGC) was disqualified in impound. The rule cited was “the radiator cannot be blocked before or behind”… and that rule, ill-suited as it is to a car whose factory radiator location is behind the engine, was now held to bar any record attempts on the Blown Gas Coupe record in its current configuration.
Okay; we’d brought the body parts required to make the Pickle into a Blown Gas Altered Coupe, and we installed them. Got through the (single) staging line at past 5pm… it would be a short impound session if we qualified, but the whole meet is short, so let’s run. Push-off at 17:37.
Brandon took the Pickle faster than she’d ever run before. Holey moley fast, boost looked strange but the fueling was spot on. The VX3 chain was little loose, but that was the chain we used for multiple runs at SpeedWeek, and besides: we had no time to change it.
The ‘strange boost’ we traced to another blown apart MAP sensor (insert complaint about globalization and offshore manufacturing) but there was a silver lining. The Pectel was fueling as if there were 10-12 PSI of boost, but there were actually 26-29 PSI of boost: and the fueling was perfect. Well: a demonstration will convince even skeptics, and we opted to set the high-boost fueling as the accident had instructed us.
Mon – Impound: we wanted to install our spare MAP sensor, but the harness connector was slightly different, and we had no time to hook it up. The databox wouldn’t know what the manifold pressure was in this upcoming Record run. That’s okay, because the Pectel MAP was still good, and that’s the one that gets used to set fueling. The manifold pressure had been a little high on the qualifier, so for “motor safety”, we took a half-a-turn out of the boost control knob. Heh.
Pickle to Team: I’ll show you some boost, folks.
Somewhere mid-run the boost control hose separated from the wastegate, and thus there was effectively no boost control. The turbo, unregulated, took manifold pressure off the chart. This let the Hayabusa reach near the programmed maximum RPM in fourth, fifth, and six gears (a first for us on the Salt). Then, at redline in top gear and at never-before-seen levels of power, at 220 mph, the left outer CV joint “stripped out”.
At that speed, something like 500 horsepower is required just to maintain velocity; it takes 500 horsepower delivered through two front tires. When the left side axle could impart no power to the left side wheel, the right side wheel got, suddenly, twice the power it had a moment before. That is, when the left side tire couldn’t deliver power anymore, all the power spilled out the right side. The tremendous dynamic forces at work uncoiled into the right-side tire, and it spun wildly, taking the wound-up drivetrain with it, dragging the engine itself up another 764 rpm above redline.
That excursion probably triggered the ECU’s rev limiter; either the limiter or some other factor cut motor power and the car began to decelerate. Good thing, as a one-wheel-drive setup at that speed would be hard to control.
It only pulled through most of Mile 4, but that was enough.
The two-run average was 213.411 mph, 10+ mph over the previous record in H/Blown Gas Altered.
Izzat a RedHat? Oh yes it is.
