Author Topic: On Speedgate's strange powergear-like behaviour  (Read 41 times)

Cas

  • Otto's Student
  • **
  • Posts: 309
  • Think different. That's OK... as long as you think
    • View Profile
    • Dimioca Labs
On Speedgate's strange powergear-like behaviour
« on: April 10, 2019, 08:40:27 AM »
R4K is currently running a race using the Speedgate XSD. We've known for some time about its very particular behaviour when quickly lowering the gears while at high speed. I remember when CTG posted a video in the shoutbox about it and most pipsqueaks felt kind of disappointed, apparently. It seemed everybody expected Speedgate to be a well-behaved, realistic car and instead, it had this quirk. Maybe so much was this disappointment that the car wasn't included in the following year's car set for the tournament.

Since that day, I've been thinking about the car and its qualities and I've started to feel some strange love toward this feature/bug... Specifically, I've began to feel that it isn't any weirder than powergear, which we have gotten used to seeing as something normal in Stunts cars (albeit unrealistic, of course). I looked up Speedgate in the wiki and there's a reference about a "mild pseudo-anti-powergear". Does this line refer to the same feature I'm talking about?  Unfortunately, I am not very knowledged about cars internals in Stunts. If this statement is about something else, then how should we call this feature?  Do other cars have anything like it?  How do you guys feel about maybe loving this weirdness a little?

Anyway, this is just a bunch of questions about how we generally feel about this car, but mostly, for those of you who have more experience creating and editing cars and can shed some brighter light on the topic. Thank you!
Earth is my country. Science is my religion.

Duplode

  • Breaths Stunts
  • ******
  • Posts: 3553
  • Through the astral door - to soar
    • View Profile
    • The Southern Cross Stunts Trophy
Re: On Speedgate's strange powergear-like behaviour
« Reply #1 on: April 11, 2019, 02:12:47 AM »
From having looked at Speedgate's RES file, I'm pretty much certain its downshift bug exists because of an abnormally high maximum RPM (byte 33h), well beyond the end of the torque curve. When you downshift a high-revving Speedgate, you don't get engine braking; rather, the car keeps its speed while revving higher than would otherwise be possible. If you do that while driving at a sufficiently high speed, you get powergear-like behaviour, which I haven't yet investigated closely enough to be able to describe in detail.

I looked up Speedgate in the wiki and there's a reference about a "mild pseudo-anti-powergear". Does this line refer to the same feature I'm talking about?

Not really; I wrote that passage long before we noticed the downshift bug. I believe the first pipsqueak to take advantage of that bug was Gutix, in his winning Z104 lap, though back then I think few, if any, among the rest of us understood clearly what was going on.

Anti-powergear refers to the ramp slowdown feature of the Countach. The Speedgate, like some other cars, is affected by slowdowns when landing from jumps at very high speeds. Nowadays I'm not actually sure if the same bug is involved in both cases, and I probably wouldn't use the term "anti-powergear" were I writing that article right now.

How do you guys feel about maybe loving this weirdness a little?

I find it rather difficult to warm to that bug because it feels too close for comfort to powergear on demand, which I tend to think of as a Niva-class anti-feature. In the past, I have even thought about publishing an alternative Speedgate with a working rev limiter... On the other hand, it could be interesting to explore which driving techniques would be needed to use the downshift bug to its fullest extent. And in any case, I will give Speedgate a go in the current R4K track  :)