13100 rpm fourbanger restricted to 9300 redline

[ptuomov]

This season, a number of wins and the second place in both the Nordic and Finnish (not certain, but virtually certain) series.

In the last race in Sweden where all cars were tested on a dyno, our car was off almost 10 hp from the top two cars (and one of the top two cars drives like an unrestricted class car in race starts, just blows by everyone). The driver definitely exceeded all expectations given this power differential, thank God for rainy weather in many races which was an automatic W for our driver.

[BLSTIC]

So did it have better midrange than the top cars given the header design?

[Kevin Johnson]

Have you replaced/renewed the electrical connectors?

Several years ago I replaced the Molex connectors, for example, (so new pins for male and female) in some stepper motors after carefully reading the engineering documents. There is a finite number of times they can be connected and disconnected without risk of intermittent faults.

[ptuomov]

So did it have better midrange than the top cars given the header design?

It's kind of silly. The car was competitive despite being being 100% legal (and it's obvious that not all cars are 100% legal) until about late June of this year, with the driver winning regularly and leading the series. Then, the car developed problems which turned out to be a fuel injector fault. I wasn't around and the people working on it tried all sorts of things that I for sure would've not tried -- they should have just found the fault and fixed it and left it alone. Instead, they also made various hardware changes. Long story short, the first time I had the time to look at the physical car in detail (and not just data) was when they came back from Sweden earlier this week. The best tune fuel map made no sense to me so I wanted to see what's up. Turns out that a person in the team had swapped in a motorcycle-style firing order to the headers (1-2/3-4 instead 1-4/2-3). Given that all the other dimensions were designed for an equally-spaced pulse 1-4/2-3 headers, of course it was down on power. It's a religious experience level miracle that the driver forced that POS to the second place in the series. Such is life.

Moving into the less restricted 15000-rpm redline 750cc class next. The driver is trying a rental car with 155hp on Saturday's race with a one-race license paid. He's really good, first time ever testing that rental car with almost double the power he was putting in very competitive times by the third lap.

[ptuomov]

Have you replaced/renewed the electrical connectors? Several years ago I replaced the Molex connectors, for example, (so new pins for male and female) in some stepper motors after carefully reading the engineering documents. There is a finite number of times they can be connected and disconnected without risk of intermittent faults.

The connectors in this wiring loom are a bit of a disaster, especially if connected repeatedly. Sometimes when a data logger is attached and it rains, the car stops and won't start!

[Kevin Johnson]

Have you replaced/renewed the electrical connectors? Several years ago I replaced the Molex connectors, for example, (so new pins for male and female) in some stepper motors after carefully reading the engineering documents. There is a finite number of times they can be connected and disconnected without risk of intermittent faults.

The connectors in this wiring loom are a bit of a disaster, especially if connected repeatedly. Sometimes when a data logger is attached and it rains, the car stops and won't start!

CONNECTORS
FAILURE MECHANISMS AND ANOMALIES

Military research on connectors

[ptuomov]

Our driver is racing against grownups in his first race in the unrestricted class, the big leagues for this car. Unlike in the junior class, it is very hard to cheat in this class because there’s no artificially low rpm limit.

He won the first heat with a huge margin and all the grownups are seething.

Now other teams are complaining to get him disqualified. One complaint about where weights are attached and chassis modifications may succeed. The race is stopped to decide the issue.

The thing is, since it’s a one-race rental car that was tested for exactly one day, and we’re doing this just to see if he’d be competitive, we set the rpm limiter to 14,500 rpm which is 500 below the rules maximum of 15,000 to save the rental engine. So we could even add some power.

[ptuomov]

If internal combustions engine car racing will continue for the next two decades, you'll likely see more of this driver:

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[BLSTIC]

Ha. Centre of gravity height is an advantage, yes. But not so much of an advantage that someone in a hire car that's down on power (and has zero experience in a car with this much, let alone what the rest of the field is running) should clean house on their first race. I mean the car isn't even properly tailored to them yet...

At least centre of gravity is an easy measurement and fix.

What other crap did they try come up with?

[ptuomov]

Ha. Centre of gravity height is an advantage, yes. But not so much of an advantage that someone in a hire car that's down on power (and has zero experience in a car with this much, let alone what the rest of the field is running) should clean house on their first race. I mean the car isn't even properly tailored to them yet... At least centre of gravity is an easy measurement and fix.

What other crap did they try come up with?

To be clear he was the first of losers. He won his semifinal and lost in the finals to the driver/team that won the national championship. Two cars got past him at the start and he was only able to scalp one by overtaking. We had a random rear shock setup, best guess tire pressure, and 14500 rpm pill. Second place. Fastest lap at every stage, so only lost anything to anyone at the start drag race.

The rules are poorly written, it was the last race of the season that decided the championship, and we dropped one of the generationally best drivers on that $hitshow without a warning. Hence the commotion. Not overtly critical of the grownup losers.

This car class has a live rear axle and the start is very important so the optimal center of gravity is further up and back and the optimal polar moment of inertia is higher than you'd expect. So a lot more about weights matters than in most racing classes.

Still, the driver is a crazy talent. Not all talent makes it, but this one has a shot. The skill level is so crazy.