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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Sun Jan 24, 2016 2:00 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
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Location: Eating tofu and legumes in my hippie shack
Ahhhh....gotcha.

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Thu Feb 25, 2016 6:49 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
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Location: Lethbridge, AB
The town of Fort McLeod is threatening to not renew the rental of the airport for the SASC. Final word will come on March 14th. Good thing I'm modifying my suspension for this season...rats.

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Thu Feb 25, 2016 9:45 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
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Crappy!

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Thu Feb 25, 2016 10:12 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
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Location: Lethbridge, AB
I'll be writing a letter for sure. Guys spend a few hundred bucks a piece per weekend (there are 40 odd guys down there, only a few of us are "locals"). Individual average seems to be around $1200 for the season these guys are dropping. It's only $50 - 60K but that money is tourist dollars and is not coming back or being replaced. Just goes to prove we need a dedicated racing facility around here that's not subject to this sort of crap.

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Tue Mar 15, 2016 9:11 am 
Haha, I just built a W24 Octo-Turbo, now what?!
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Fort Macleod is ON for this year. 6-1 vote at council last night. Now to figure out if I can get out of street modified that would be fantastic. The new heritage classic classes have reasonable handicaps but are only for 1974 and before MODEL year cars so we missed that boat by a year. Maybe with the new suspension and new tires things will work a little better this year.

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Tue Mar 15, 2016 9:32 am 
Haha, I just built a W24 Octo-Turbo, now what?!
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Joined: Thu Dec 29, 2005 12:29 am
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Location: Eating tofu and legumes in my hippie shack
Excellent news!

Didn't you mention something about a new classic European category with almost zero restrictions? Or was that the heritage classic?

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Tue Mar 15, 2016 2:52 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
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Joined: Wed Dec 21, 2005 8:40 pm
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Location: Calgary, Ab
Wow, I just had a look at the Heritage Classic rules... They're pretty wide open! No mention at all of engine displacement, sway bars, chassis components, alignment settings, wheel diameter or width, track width, or anything like that. All it needs is full equipment, full interior, and tires with a treadwear of 200 or higher and you're in the street category.


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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Tue Mar 15, 2016 5:09 pm 
First volvo in outer space
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Location: East L.A.
Great news!! Good to hear that there will be a little bit of Motorsport available in Southern Alberta.

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66 122S (Garage Queen)
89 244 (Hers)
90 745Ti (Mine)
89 744 (SOLD/Bought back for other daughter)
78 242GT (Project... LOL)
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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Wed Mar 16, 2016 8:41 am 
Haha, I just built a W24 Octo-Turbo, now what?!
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Joined: Wed Jun 14, 2006 4:19 pm
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Location: Lethbridge, AB
Ugly Duck wrote:
Wow, I just had a look at the Heritage Classic rules... They're pretty wide open! No mention at all of engine displacement, sway bars, chassis components, alignment settings, wheel diameter or width, track width, or anything like that. All it needs is full equipment, full interior, and tires with a treadwear of 200 or higher and you're in the street category.



Well, you're in the street category...I'm in SM. I'm going to have to drive a lot faster to stay ahead of you on PAX.

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Thu Apr 28, 2016 9:02 am 
Haha, I just built a W24 Octo-Turbo, now what?!
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Location: Lethbridge, AB
HCR will be rulled by my 122 when it's done...because I'll be alone and have a much better PAX (the handicap system).

OK - I promised a race report and here it is. We had a cold day on Saturday for testing and other than the completely foreign way that the car handles (flat with grip...WTF) it was good fun. Got a few tips - apparently I'm a bit timid and don't use my brakes enough. Had one of the instructors jump into his prepared Honda S2K and give me a demo on slicks as he couldn't really explain it very well. Now that was a fun ride - stripped out, fenders cut out by hand, no windshield or posts (just a little tape over the sharp stuff, single layer fiberglass doors that are on pins...no hinges. Unfortunately their lack of attention to detail meant that it broke (he blamed the car - I'm like..."say nothing". Anyway, the 242 is pretty good. The best part of the novice school was that I actually started to learn things.

Last year everyone was telling me (in the autocross club forum) to work on my driving and not worry about the car. Everyone except the instructor at the school, and he's a multi-time SCCA national champion and his opinion was that I was wheeling this crate as fast as anyone else and that in a fast car I'd be fine. That's always sort of sat there in my head. I'd say things like "well, you're not driving my car." and smile when guys would rib you for being last yet again. I mean, you can be slow and sloppy in an S2K or Miata and still be faster than me. In fact, that's still true.

What did all this work prove - you need to get the handling demons out of your car so that you can limit the things going wrong to just you - then driving technique can improve. I think we're there folks. Trail braking does make a difference (last year...nope), apexing corners properly or slaloming was never fun when you're half motion sick as a result.

So on to race day. Sunday's weather was foul and I've got to run with the big boys with race slicks and fancy high powered cars because of where I'm classed. We loose the coil toss and the "street" guys with tread on their tires select to go second. No one is happy in my group. Guys are slipping everywhere and at one point I was faster than a C7 Corvette (he had 4 cones worth of penalty). Lost 6 seconds from my first run to the last run. Fastest last is the way I usually drive - more consistent than last year from run to run (cut 4 seconds right off the bat). It's hard to gauge where we're really at as I'm not last in this group but my position makes no sense as guys are spinning out and collecting cones like a hoarder.

We're up again just after lunch and the conditions have gotten worse. Standing water now and I'm still searching for grip. Still learning how to use the brakes (which could use more initial bite in my view). I did manage to get a really impressive tank slapper going through a fast transition. What I learned by driving through it (hands going a little fast, so after the first correction, I'm causing this entertainment) is that I never lost the front end. It's gripping - the rear...not so much. Now even in these horrid conditions, I'm only a half second slower than the AM runs. I'm happy with that effort.

Then in the last run, the street guys get a drying track and by their last run, the line is dry and we're hearing tires. They're going for broke. I end up second last. The deck is well shuffled - sure the fast guys are still fast, but there are guys in that group that I would have beat if I was running in the dry (ah racing excuses - aren't they great!).

Analyzing the RAW scores tells a different tale. Last year the average of my runs (full season) indicates that the car was consistently around 75 - 76% the pace of the fastest runs. With an overall best of 77%. Sunday, I was 85% of the top run. I should also mention that the only cars out were the serious people. I think there was only one rookie/maybe two buy they both had previous experience. Look, more excuses. I was nipping at the heals of a few other cars that I was a long way away from last year (maybe a better comparison?) - like get another second per run or so and I'm past them.

Here are the raw results:

Overall ranking by raw time:
Rank Car# Class Driver Car Raw Time Score
1 82 SM Matthew K 2004 Subaru Impreza 124.297 100.000
2 88 DS Stephen H 2008 Mini Cooper S 126.217 98.479
3 888 SM Joseph G 2013 Scion FRS 127.338 97.612
4 192 SSP Cam W 2010 Chevrolet Cheve 127.342 97.609
5 110 HS Reijo S 2015 Ford Fiesta ST 127.596 97.414
6 5 BS Murray P 2002 Honda S2000 127.625 97.392
7 510 BS Jens-Timothy H s2k 128.215 96.944
8 78 DSP David G 1992 Mazda Miata 129.737 95.807
9 86 FS Chris S 2005 Infiniti G35 130.057 95.571
10 101 HS Nicolas F 2015 Ford Fiesta ST 130.469 95.269
11 193 CS Andrew L 2015 Scion FRS 130.755 95.061
12 60 ES James C 2003 Mazda MX-5 131.133 94.787
13 93 CS Quentin O 2015 Scion FRS 131.162 94.766
14 51 FS Richard B 2005 Infiniti G35 131.301 94.666
15 202 SM Paul T 2013 Nissan GT-R 132.128 94.073
16 930 FS Matthew R 2005 Ford Mustang GT 132.330 93.930
17 8 CS Terry J 2015 Mazda MX5 GS 132.398 93.881
18 539 SM Zach S 2006 Subaru WRX STi 132.749 93.633
19 31 ES Julie T 2003 Mazda Miata 134.245 92.590
20 2 SSM Jeremy K 1989 Toyota MR2 135.813 91.521
21 312 SSP Tom G 2010 Chevrolet Corve 136.384 91.138
22 98 STR Myles B 1999 Mazda Miata 136.653 90.958
23 92 CSP Jess W 1994 Mazda Miata 136.775 90.877
24 54 BS Gordon P s2k 137.042 90.700
25 401 SM Mikael G Volks R32 137.118 90.650
26 65 AS Derrick K Ford Shelby GT350 137.351 90.496
27 463 GS Daniel O 2013 Ford Focus ST 138.284 89.885
28 14 FS Tom M 1989 Ford Mustang 139.313 89.221
29 148 STX Zachary B 2015 Subaru BRZ 139.397 89.168
30 420 SMF Jason P 1990 Toyota Celica 141.597 87.782
31 1 GS Kole M 1995 Mitsubishi 3000 142.206 87.406
32 244 ES Ryan S miata 142.703 87.102
33 210 CS Eric K 2005 Nissan 350Z 143.669 86.516
34 105 BS Jo P 2002 Honda S2000 143.862 86.400
35 242 SM Craig C 1981 Volvo 242 GLT 145.493 85.432
36 160 ES Cole M 2003 Mazda Miata 147.966 84.004
37 84 BSP Evan W 1994 Subaru STI 149.534 83.123
38 69 EM Bill R Lotus 7 Replica DNS 0.000
39 412 EP Artur M 1989 Opel Kadett DNS 0.000

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Sun May 15, 2016 6:41 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
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Joined: Wed Jun 14, 2006 4:19 pm
Posts: 3006
Location: Lethbridge, AB
With all the fun this past week getting the ECU working - I was really lucky to get this thing going for this race weekend. Due to the number of newbies out, they ran another novice school. So, what the heck, free instruction...I'll take all I can get. I also have my action cam working now. I've recorded a bunch of videos even though it wasn't really optimized. No stabilization and the stupid date stamp. Anyway, you can see what kind of things we're learning...and then my implementation.

Take home good points (aside from the ECU problem solved and not worrying about the brake calliper bolt that fell off) - I was only gaining around a second over my last three runs...so I was faster earlier instead of banging in the fast lap right at the end. Other than missing a gate on my first run, I was clean and 84% as fast as my class leader. So that's still pretty good.

Tires still are not providing epic amounts of grip...better than last year, but still lots of sliding. Let some air out of the rear for today and it helped a lot. I still could be more assertive on the track and will work on it. At this point, I'm half thinking about trying to find a beater set of wheels and putting something sticky on them.

For your viewing pleasure.


https://youtu.be/bLY7ut3Di7I

https://youtu.be/gX19x4ItTBc

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Wed May 18, 2016 1:36 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
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Joined: Wed Jun 14, 2006 4:19 pm
Posts: 3006
Location: Lethbridge, AB
I'm trying to generate a little science on setting the car up, so as a start point here's where we sit as of this moment (the front is a bit lower than shown due to the uneven surface)

Image


https://youtu.be/bLY7ut3Di7I

The rear is pretty loose. I tried playing with tire pressures and that tuned some of the tail happiness out of it, but that long sweeper (a feature where we run) is terrible for this car. You can see that I take the long way through the slalom on the way back just to get the car on a better line through that corner (tried it both ways) and I have to be very careful to not unsettle the car coming into sharp transitions or it's tank-slapper city.

So I'm going to start over the long weekend taking some measurements of ride height and rake and play with how this all impacts grip levels. I'll create a table and record what I find. The car should hook up better than it does. So stay tuned as we get tuned.

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Thu May 26, 2016 9:00 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
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Joined: Wed Jun 14, 2006 4:19 pm
Posts: 3006
Location: Lethbridge, AB
Quick update...I think I may have found the cause of the tail-happy nature of this car. I got some conflicting information at the races for what I should do...change the rear bar, more front bar, change shocks, take some air out of the rear tires, more air in the tires. It was a little hard to process. What I did know was it was still a slippery handful.

More reading and limiting the conversation to a few people that know lead me to jack the pressures up...way up. Bingo. That works. I tried it the other day and noticed that my brakes felt more effective, corner grip seemed better. I went from 36/30 PSI F/R to 48/46 PSI F/R. We couldn't really test it in all situations, but it sure did feel better to me. We'll see at the school in a few weeks.

I also measured tire temps (I do have a tire pyrometer...why not use it) and I found that they were consistent during my test - so no reason to rebalance the car right now as both front and rear seem to be working about equally. I'll be measuring this and recording it at the race school coming in June.

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Fri May 27, 2016 9:53 am 
Haha, I just built a W24 Octo-Turbo, now what?!
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Joined: Wed Dec 21, 2005 8:40 pm
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Location: Calgary, Ab
Nifty.

I had a bit of a paragraph going and started looking for an article I read 30 years ago in Road & Track, but found something else instead: http://www.performancesimulations.com/w ... -pressure/

tl/dr: Avon published some tests on racing tires showing contact patch relative to tire pressure and load, using F3000 front and rear tires. Tire pressure has less to do with contact patch than expected, wider tires have more contact patch at a given load and pressure than a narrow tire (surprised me), and if you believe ALL the data, some strange things happen with tire pressure on the front tires. Skeptical me says they reversed some data on the front tires between 24 and 28 psi, but take that for what it's worth.

Racing tires tend to like pressures way below 30 psi, and I've seen many Nascar races where race teams will run fastest when the tire pressures are lower than the minimum recommended by Goodyear, until the tire fails and the car plows into the wall. All, and I mean ALL, of my experience on street tires tells me that more pressure gives more grip (on dry roads) and more responsiveness, but I've never driven a race car.

Common racing lore is that lower the pressure to get more grip, and more grip comes from greater contact patch. Lowering the tire pressure in the front generally increases front grip, and vice-versa with the rear, suggesting that lower pressure = more contact patch = more grip. Avon's published data suggests that contact patch doesn't come easily, and you have to cut half the pressure (or double the load) to get a 50% increase in contact patch (should double, theoretically). But there you have it.

My personal feeling is that on a race car, the chassis is so stiff that lowering the tire pressure reduces front roll compliance just as much as reducing the sway bar, plus it increases grip over smaller bumps (basically the whole car becomes "sprung weight", with only the bottom of the tire carcass moving up and down). A street car is so much less torsionally and laterally rigid than a race car, playing with tire pressures doesn't alter lateral load distribution one bit. It still helps balance the chassis, but mostly in crispness and turn-in.

On street tires, raising the tire pressure stiffens the sidewalls and the carcass and doesn't let the tire tread squirm as much and the tire generally performs better. What happens with the contact patch? Well with the generally stiffer tire I predict that contact patch changes even more disproportionate to tire pressure, and with the higher tire pressures on a street tire you've got to make an even greater change in pressure to get any change in contact patch. Tread blocks on a stable carcass squirm less and generate less heat and more grip, so increasing tire pressure brings more benefit here.

That's what I believe, anyway.


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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Sat Jun 11, 2016 8:19 am 
Somehow completely sideways in 4th

Joined: Thu Nov 10, 2011 11:43 am
Posts: 238
Location: Regina, SK
Hi Craig,
Has anyone suggested chalk on the sidewalls to during your runs to set tire pressures? Essentially you use chaulk on sidewalls to check if the side wall is rolling too much. Increase tire pressures until the chalk only wears off on contact patch and isn't coming off higher up sidewall.

Rabin


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