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Re: [EVDL] 2SSIC Barona Report <long winded>

To respond - I still have a lot left (600 amps) plus a few volts plus (very
important) changing my rear end gears. I think that for drag racing, and
especially racing Zombie, I'm going to need to go from 2.71's to probably
3.2 - 3.3's. This may very well endanger my rear axles, but that was always
a known risk :)
But one step at a time. Right now I can't crank up my amps and higher
because I don't have enough rear brake action to slow down quickly enough at
the end of the track to go any faster at Barona, which is one of the reasons
I didn't (thanks for the proportioning valve recommendations, I'll be
ordering something soon).
The other question is how come my front wheels lifted, just barely, off the
ground in Portland at 1100 amps with over-inflated street tires, but not at
1400 amps with 26.5 x 9.5 slicks at 15 PSI. I haven't been braking loose
the tires. I've shaved 2/10 my 1/8 mile speed and picked up like 4 MPH
which I figure would put me right where Wayland said 12.6-12.8 1/4
Also VERY important is for me and the car to get more experience. She is
AMAZING to drive, and with the exception of the 2nd run in Portland where
she lifted (barely) complete control and response. Did I mention how
amazing it is to drive her?
Lets see as to the steering problems, It was not the allen's that were the
problem. They all have small indentations that they fit in. The problem
was that somewhere along the way one of the u-joints was put on in the wrong
place so that it was lined up with a flat bar instead of the indentation.
Fixed.

So to wrap up - I figure I've got 40% left in power about 8% I can safely
add in voltage 20% in gears (to optimize for the 1/4) which means I have
about 80% left to go before I start dropping weight - I can loose 100 # in
the rear end 50 # in the front lower A arms and another 50-80# in the
wheels, and in a worst case scenario 120# in the driver (pro / jockey). Now
for reality the 200# to the car (10% + ) I probably don't have money for
now. The 80% I've got left, well I need to increase my brakes so that I'm
using the rears, then I can also looking at putting narrow front tires on.
But I need more experience because this is an AMAZING amount of power, and
deserves respect.

KD

-----Original Message-----
From: John Wayland [mailto:[email protected]]
Sent: Sunday, August 26, 2007 5:02 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] 2SSIC Barona Report <long winded>

Hello to All,

Micheal Kadie wrote:

>Day 2 I did a 7.83 followed by a 7.80/7.81 I'm not sure



Way to go Michael, for getting back out to the track and running some good
1/8 mile times in front of the Speed Record channel guys!


Ryan Stotts wrote:

>7.80 = 12.246 1/4 mile? Nice! Think you will be in the 11's next
>time out with the power cranked up?
>
>
>
Michael's 7.80 second 1/8 mile ET will not translate to a 12.2 second
1/4 mile ET, unless his EV's electric drive train performance is
completely unlike all the others I've seen over the years in drag
racing...and I can tell you from first hand experience with his car,
that it is not. If it were an AC powered machine with say, a 350kw AC
system that would have strong high rpm horsepower like an ICE powered
gas car does, then maybe. A big high-torque'n DC drive? No way.

If you use conventional gas car race calculators, which I assure you
did, then your estimate of a 7.80 second 1/8 mile ET translating to a
12.246 second 1/4 ET is pretty close. I've got perhaps 50 times slips
right in front of me at the moment, and I can verify this in regards to
what 'an ICE powered car' does..keep in mind, this is only if we were
talking about an ICE gas car and not an EV drag car.

We raced against a hot tweaked turbo Dodge Neon ricer a few weeks ago
when we ran our 11.8 on lead acid. His stout four banger turbo ran an
impressive 12.280 @ 110.7 mph after running a 7.756 second 1/8 mile.
This was your typical gas car that has its best acceleration when its
ICE is revved to its power band, and in this car's case, to where its
turbo was on full boost and the top speed was really picking up...the
exact opposite of 'most' electric drag cars at this time in our electric
drag racing development. Keep in mind that in this example, the 1/8 mile
ET was a bit quicker than the example 7.8 at an even quicker 7.75, and,
it was a turboed car, the type that generally has a better second half
mph than non-turboed cars have, an yet it was shy of your 12.246 with
its 12.280 ET. Nonetheless, the gas car calculator was at least in the
ball park.

You cannot merely look at a racing calculator designed for gas cars and
accurately predict an EV's performance. The same gas car calculators
show White Zombie as having 386 hp to do its 1/4 mile ETs while we know
for a fact from our sagged voltage and delivered motor current, that we
are making closer to 260-300 hp at best.

Now, with those same 50 some-odd time slips in front of me, I looked for
some of White Zombie's slower times such as when we either had cold
batteries, or had turned down the juice for some reason, so as to show
you what an electric drag car's 1/4 mile ET really is when its 1/8 mile
ET is 7.8 seconds. Unfortunately in this pile of time slips, none of our
1/8 mile ETs are that slow. The slowest I did find though, is a 7.74,
which is still quicker than a 7.8, and that 7.74 produced a 1/4 mile ET
of 12.433...that's a quicker 1/8 mile ET that is still not strong enough
to get anything more than a 12.4.

It only takes small differences in the 1/8 mile ET to make BIG
differences in the 1/4 mile ET. To demonstrate this to you, I went to
one of my favorite electric drag racing
resources...www.plasmaboyracing.com, then I clicked on 'White Zombie
History', then on 'Early 2005', then looked under 'Races and EVents',
where I found a photo of my own hand holding a time slip from the
Woodburn drags where Tim Brehm first started driving Zombie. The time
slip is easy to read, so you might go check it out. It shows a 1/8 mile
ET of 7.917 seconds (slower than the 7.8 we're talking about here) that
resulted in a 1/4 mile ET of 12.638.

Don't misunderstand me on this...I think Michael's car is cool, and I'm
thrilled that he is out there perfecting his car and running at the
track. My hat's off to him and I am looking forward to seeing how he
continues to improve his car and his drag racing skills. I think he's on
his way to a mid 12 in the 12.6 range, based on his current 7.8 second
1/8 mile ET. That's a very impressive ET and it's one that will make his
car a force to be reckoned with at the drag strip. It is however, a long
ways away from a low 12, such as the 12.2 you posted his current best
1/8 mile ET translates to. When he starts running in the 7.6 range for a
1/8 mile ET, that's when his EV will be turning out 1/4 mile ETs in the
12.2 second zone. I have no doubt, that he'll get there. I look forward
to when he runs a 7.5 second 1/8 mile ET that will push his EV into the
high 11s!

See Ya....John Wayland



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