> Bob Monday said...
>
> I've had trouble with Geez trimming off the start of my runs. The
> "trim" option is off. My start threshhold was set at .4g, something I'd
> done when using a mod car and before the "prostart" version. Since Ft.
> Myers, I've moved the threshhold back to .2g, and am hoping that the
> problem was that my poor tired Neon was taking more than 5 seconds to
> hit .4g acceleration. (Not that I believe it... but I had to try
> something!)
Bob has told me about this before, and I've never seen it.
Anyone else have a similar experience? Or do we all chip in
to fix Bob's "poor tired Neon" problem. Poor-tired...I
don't think your tire sponsor would appreciate that.
;-)
> Also, how accurate is HP given that I've entered accurate car & driver
> weight? Are there things which will spike HP? I got some unusually high
> numbers at Ft. Myers, and it wasn't because of a shift or something.. I
> was well into 2nd gear. If those numbers are true, Chrysler was
> "conservative" on the SOHC ratings. They wouldn't lie about that, would
> they? (Thinking of the hemi-NASCAR-insurance days... and Celicas.)
I'm assuming that you've already verified that the settings
on your horsepower gage are what you want. You aren't using
gross adjustments when you expect to see net numbers, or
something like that. So assuming that...
The HP is based on acceleration times speed times weight.
So assuming that weight is correct, that leaves acceleration
and speed. Check that the points on the course that you are
getting this high hp numbers have realistic speeds. If the
speed has crept up due to a lot of oversteer, or other weird
slip, or just normal mathematical drift, correct it with the
adjustments screen. Usually if the end speed is about
right, the rest of the run will be about right too.
However, I bet that's not the problem. I'd bet on the
acceleration. Here's the scenario. Mark Daddio gave me his
runs (recorded with a G.Analyst) from Nationals in 1998, and
his little Neon was pulling some pretty terrific hp numbers
in spots too. I figure he was hitting the nitrous button
and didn't realize we'd be able to detect that. That would
also explain why he's so bloody fast. But I also noticed
that this happened at the end of turns. And the accel chart
contained a serious spike at the end of each turn which of
course resulted in the big hp spike. It occurred to me that
what Mark was doing was intentionally spinning the front
tire at the end of the turn by getting on the gas too early
and spinning the tire while it was still "light". Then when
he would come back to straight the weight of the car would
fall on the tire, and he'd collect the boost of all the
kinetic energy stored in the driveline as the tire hooked
up. Kinda like dropping the clutch at the end of each
turn. As the tire hooked back up, the g's would spike up to
an otherwise impossible number, and with it, the HP. Mark
later confirmed that this was part of his setup. By the
way, if you have old copies of North American Pylon, I wrote
about this exact thing in an old issue, something like
December of 98 or Jan of 99.
You already have Mark's run on your disk, it's one of the
standard demo runs included with your software. To see what
I'm talking about, pull up the run that's saved as
"DADIO-N3.GAD". (Be sure your "Files of type" includes "GAD
files" so you can find this run.) Look at the spikes on the
accel chart at 10.4, 27.2, and 39.3. If you use gross
ratings, depending on your frictions, drag, and tire size
numbers, you can see 161 hp out of Mark's Neon.
If that's not it take your car straight to impound. ;-)
--Byron
>
> Bob Monday
> Do You Yahoo!?
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