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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Thu May 07, 2015 3:57 pm 
0-60 in VERY FAST

Joined: Sun Aug 27, 2006 7:34 am
Posts: 169
Location: edmonton
these were posted up on our club site. might be worth a look for those interested in improving their skills.
Me for one :D The first link is the Guys channel, the second two are where he anylizes the runs.
All of these can be found on his channel.

https://www.youtube.com/channel/UCbHUCN ... FgFwCXdTjw
https://youtu.be/KkijzcoGktQ
https://youtu.be/fzr2ffrwoQQ


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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Thu May 07, 2015 9:02 pm 
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
Awesome - keep them coming. I'm reading a few books and watching a lot of video. Can't wait for school to start.

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Sun May 31, 2015 10:40 am 
Haha, I just built a W24 Octo-Turbo, now what?!
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Location: Lethbridge, AB
After my last effort I knew that the rear was not really up to the challenge. The rear end was original to the car and was really showing it's age. On deceleration it would howl and it was getting pretty clear that I should rebuild it regardless. So, with only one month before the next event, I had to get it rebuilt. I had bought some of Kaplhenke's lower trailing arm bearings in the winter to deal with the lack of rear roll compliance. All the work that I'd done before painting things was showing the 5 winters of driving.

So I started to gather up the parts to do the rebuild. In my parts stash, I had a vintage Dana PowerLok to add some needed limited slip. It just needed a clutch pack and I didn't know if the cross shafts were broken or not. My parts guys managed to find the clutch pack and bearings.

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Note the additional two bearings for the pinion should they be needed...and they were. The standard rebuild does not work for my particular 1030. I'll explain in a sec.

Yes, this box came over on the Arc.

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Here's the PowerLok - it's a little gross inside and if you ever rebuild one...mark the case, it only goes together one way.

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I tried to pull the bearings the right way...

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That didn't work so I broke out the grinder, cut the cage and released the bearings and brutally hacked off the inner race. No pictures of that...just be careful.

The cross shafts appear fine - though very dirty.

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The side gears and parts look fine.

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Other things that needed addressing were there lack of a proper parking brake due to the aluminum brake hats, so they went into a local machine shop to install a steel sleeve. With new pads, they are perfect.

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I converted my panhard rod to be adjustable by using a 3/4-16 tube nut with 1" OD which fits into the larger diameter section of the panhard tube and a bolt that I cut and added to the other section after removing around 3" of the skinny section. Then all these parts went into the powder coaters. Sandblasted and all pretty now.

I was hoping that the poly bushings would be able to be re-used...much folly. No chance. I found that the Whiteline bushings shells were made for Aussie winters, not Canadian winters and they had rusted solid and needed to be burnt and cut out. Very messy. I also found that the bearing inner shells had almost disintegrated in the short time they were installed. So IPD to the rescue with a set of SuperPro's for the rears (more shipping, more stress of "are we going to get the parts in time".

I also had big issues with pinion parts - this car has a 1030 with a 1031 ring gear and pinion (the larger 7.75" ring gear) - this was an uncommon set-up and even more uncommon was the fact that while I needed the 1031 large pinion bearing and cup, I needed the smaller 1030 front pinion bearing. It's not very common, and was harder to find. Adding to the stress of getting this job done.

While I was waiting, I polished the case (well, of course I did).

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Then a fresh coat of POR-15 semi-gloss black.

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Brakes were repainted as during our shake down drive to Portland, we lost a brake line and the roadside repair damaged the cheap DupliColor brake paint which is total crap. The POR brake paint is much better but harder to get a smooth finish. I didn't try very hard, but it looks OK.

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Well, all the parts came together with one week to go, so I get it done in a final thrash and with differential set up and all sorts of things coming at the last minute. The rear with all new fasteners and parts all ready to go. It took just a day to get it installed and the brakes bled.

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New brake lines on the rear and some fancy clamps to secure them to finish the job.

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Everything was anti-seized within an inch of it's life and I hope this repair lasts a good deal longer than the last one.

And off to school we go. Racing school that is.

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Sun May 31, 2015 11:22 am 
Haha, I just built a W24 Octo-Turbo, now what?!
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Joined: Wed Jun 14, 2006 4:19 pm
Posts: 3131
Location: Lethbridge, AB
My racing number plates came in with a few days to go (didn't need numbers for the school, but who cares).

I waxed up the car - guaranteeing rain and drove out to Fort McLeod (first read drive on the new rear end).

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Lots of fast stuff out there with everyone learning a lot. Corvette's, GTR, Porsche, and the Ford ST's all showing everyone up. In my past efforts, the car couldn't get the power to the ground with the open differential and it just didn't want to turn. Now, some of this was me learning how to swing the barge around, but it wouldn't turn for the pro's either. I didn't reinstall the rear sway bar (the 25 mm from IPD) and with the new LSD and suspension parts I was hoping it would be better.

I had taken it in for an alignment (Friday afternoon for a Saturday event!) and found out the bad news. The BEST they could get for front end camber was basically 0 degrees. This is not uncommon for 240's where the spec is something like 1 degree positive. Being a strut style front suspension means there is no camber gain with wheel articulation. So what you have at static ride height, is what you have. As the car turns, camber allows the contact patch of the inside front wheel to stay engaged with the road surface increasing grip. What I had was 1 degree positive on one side, and -0.6 degrees on the other...the last guys to align this car were meat heads.

Passenger side...room to move.

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Drivers side...maxed out at -0.1 degrees.

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So I either cut the towers off and replace the tops with strut bearing plates or I can just extend the Lower Control Arms to get more from what I've got. I've got arms on order.

So, I arrive at the school bright and early with my somewhat wet, but shiny car. Then during the driver brief, I find out the run order...guess who's up first (because I was first to register)...yup, the slow guy in the Volvo with the damn racing numbers and no experience. Oh boy.

I get the young instructor first. He's stoked to be in the old car (funny, I always think of this as my newer car). We get two runs with me up first so he can see what I'm doing and comment. I've never driven this set-up and have no idea what it will do...and I'm looking at the sea of cones and trying to remember which way to go through things etc. I was super focused and living in fear that it would be as bad as last time.

We're off - new elements to try like a box, and some fast sweepers...my nemesis is the quick turn arounds and the slalom which just are hardest with the way it handled. No time to worry, just have to think about "what's next" - box and set up go fine, then the slalom - it's not great, I'm turning too late. I've got more grip for sure and can weld my foot to the floor when needed. First big turn and it doesn't push as bad...hey that's not bad. Gotta keep my head in the game as you've got to do the slalom on the way back then on to another sweeper, slalom, decreasing radius turn around, slalom and finish.

Whew - first run done. I'm pretty stunned that it was that good. So next time I push more. Then he drives and monsters the slalom...he's making a left turn as he's on the right hand cone...watching what the pros do is hard when you're trying to just remain in the seat. He's essentially driving out of phase with the corners (he was impressed that I caught this detail...I didn't want to tell him that I'm a nerd...though driving a Volvo is a dead giveaway). So after he goes twice, I go again. Making improvements - getting faster. Got a round of applause as I moved off the course from the GTR owner...that felt good.

Time - 10 seconds faster on essentially the same course and conditions as last time. Holly crap - that's better on a 50 second course. I was initially 5 to 7 seconds better than my previous best of just under 58 seconds (which was much slower than the rest of the field).

This continues for the next instructor - little tips. I'm told that my inputs are smooth and progressive and that I've got good car control. Still lots to learn, but we're really working on details rather than having them yelling at me to put my foot to the floor. Then all heck brakes loose. We have changed the track configuration to be faster and we get a third gear shift. New instructor at the wheel...one of the really experienced champion SCCA guys (there are two of these). He's flat out and the car starts to misfire. WTF that's random. He's thinking it's fuel starvation and we're pedalling it to the finish (still he puts in a 49 second effort).

After my runs, it's off to the pits.

I think it could be too much boost or something (compressor surge...what is that again?), what would spark blow out feel like? Weird. So I have a look and everything looks normal, nothing on any gauge (though it's not like you can look at a boost gauge when driving). I remove the manual boost controller...should have waited for things to cool off, but I'm a bit out of sorts. No one comes to look or help or anything. I can over hear the fat guy in the Honda making remarks about my classification in SM...hey douche, I can: A. Hear you. B. Your Civic should be crushed. C. That's what happens when you build outside of the rule book and I don't care if I'm last every time.

So MBC is removed when I notice this.

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That line connects to nothing and is normally capped. Where did the cap go? Could this be my issue? Who knows, but I grab some tape to tape it shut and then find the cap sitting by one of the injectors. Sort of wedged in place. How lucky is that. Replace it, and tape it. That does seem to solve the problem, though I'm down at 7 PSI (totally doesn't matter).

Last runs go well, back to lower speeds, but still no issues. Then the heaven's open up and we get drenched - thunder, lighting. I've got 3 runs left and we're all keen to get them in without instructors. Last lap was my best wet lap at 53.79 which was 7 seconds faster than Civic-boy...fastest guys, like heavily modded S4 Audi and Cayman are only hitting 49 seconds. That felt great. School main instructor Tim, came over after that session (when they called the even due to lightning strikes) and shook my hand and gave me a high five. He's so enthusiastic - many complements on the car and driving. That was money well spent...and it was a lot of money.

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Sun May 31, 2015 12:59 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
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Joined: Thu Dec 29, 2005 12:29 am
Posts: 1790
Location: Eating tofu and legumes in my hippie shack
Amazing work Craig! That's a significant time improvement!

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Mon Jul 13, 2015 7:09 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
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Joined: Wed Jun 14, 2006 4:19 pm
Posts: 3131
Location: Lethbridge, AB
Someone over on Turbobricks asked which handles better, a 122 or a 240. I said a 122 - I was sort of ignored as the masses went off on a variety of tangents. I then shared some of the analysis that Matt and I had done this past winter to show that the 122 suspension was pretty decent for a 60's car but could really use improvement. The 240's is, well, simple and cheap to mass produce.

From last Sunday's autocross - Dave Major (Rojam on the board) was kind enough to do the photographic work that I really wanted done on these two cars. What a chance to get a bone stock 122 and a modified 240 and compare. For the record, the runs shown differed by 2 seconds and I'm guessing the 240's got about 80 more horsepower than the 122.

Let's have a look shall we.

First major braking zone coming into the really stretched out (like 32 paces) slalom.

The 242,

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The 122

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Note that I've generated some tire smoke and cost myself some time. Body lean - about the same.

On to the slalom.

The 122:

Matt's never done this before - but you can see he's turning for the next cone as he passes the cone. That's skill.

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Between cones - level and heading to the next corner.

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This picture is a thing of GD beauty - wheels straight - eye's/head looking for the next target. Textbook driving.

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Here comes the 242:

You have to get it rocking to get it to go through the slalom.

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Hey, at least I'm looking in the right direction. Note the inside tire has lifted and the outside tire is rolled over.

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Slightly more dramatic shot.

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GRIP (please)

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122 into the next big braking zone - limiting straps holding.

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There they are working again.

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242 at about the same point.

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So what have we learned...I'm guessing that these cars are a lot more alike than either one of us will admit.

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Mon Jul 13, 2015 7:20 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
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Joined: Wed Dec 21, 2005 8:40 pm
Posts: 3492
Location: Calgary, Ab
THANK YOU, DAVE! Great shots! I'd like to get my hands on some originals one day, if I can?


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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Mon Jul 13, 2015 9:24 pm 
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
Sweet shots! Great to see this stuff up closer.

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Tue Jul 14, 2015 9:50 am 
Haha, I just built a W24 Octo-Turbo, now what?!

Joined: Wed Dec 21, 2005 8:03 pm
Posts: 2859
Location: T2C
Interesting to see that on hard cornering the outside wheel is perfectly vertical and even though the tire is rolling a bit you have 100% tread contact on that tire. It looks like you have too much steering angle at the end of the back straight. Going to take a while to figure out how much input it needs to make it turn at the limit. I suspect it's not as much as you think...

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'67 123GT
'67 122s
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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Tue Jul 14, 2015 2:20 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
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Joined: Wed Dec 21, 2005 8:40 pm
Posts: 3492
Location: Calgary, Ab
122_Canuck wrote:
Matt's never done this before - but you can see he's turning for the next cone as he passes the cone. That's skill.

Image

Between cones - level and heading to the next corner.

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You can see that in both of these shots, I'm looking at the cone I'm trying to miss. It's too late for those, I should be looking at the cones ahead. Oh well, next time I'll concentrate on that and I'll try to learn what the car likes to do in the meantime. I was mostly worrying that I'd get the car whoad up in time, so I was hitting the brakes WAY early most of the time.


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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Tue Jul 14, 2015 4:00 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
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Joined: Wed Jun 14, 2006 4:19 pm
Posts: 3131
Location: Lethbridge, AB
Pylon wrote:
Interesting to see that on hard cornering the outside wheel is perfectly vertical and even though the tire is rolling a bit you have 100% tread contact on that tire. It looks like you have too much steering angle at the end of the back straight. Going to take a while to figure out how much input it needs to make it turn at the limit. I suspect it's not as much as you think...


I've booked the practice session at Fort McLeod for the 25/26th event just to figure that out. I'd still like to see the inside tire planted. When turning and braking, that's the one that loses adhesion - for good reason.

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Sun Jul 19, 2015 12:05 pm 
Cams + Headers

Joined: Thu Mar 31, 2011 9:15 pm
Posts: 67
Location: Lethbridge
Awesome thread! Great pics! It will be interesting to see your Canuck in the same situations!


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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Sun Jul 19, 2015 7:43 pm 
Haha, I just built a W24 Octo-Turbo, now what?!

Joined: Wed Dec 21, 2005 8:03 pm
Posts: 2859
Location: T2C
122_Canuck wrote:
I'd still like to see the inside tire planted. When turning and braking, that's the one that loses adhesion - for good reason.


If you're turning and braking you're doing it wrong... :D I think more brake bias in the rear might mitigate some of the front lockup you're experiencing. I didn't see one rear wheel lock up, even under heavy braking. Maybe next size up on piston size in the rear calipers...get some more bite back there?

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'67 123GT
'67 122s
'99 AMG E55T


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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Mon Jul 20, 2015 7:54 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
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Location: Lethbridge, AB
Pylon wrote:
122_Canuck wrote:
I'd still like to see the inside tire planted. When turning and braking, that's the one that loses adhesion - for good reason.


If you're turning and braking you're doing it wrong... :D I think more brake bias in the rear might mitigate some of the front lockup you're experiencing. I didn't see one rear wheel lock up, even under heavy braking. Maybe next size up on piston size in the rear calipers...get some more bite back there?



Yup - I know the technique. Instituting it at one turn per second or so doesn't always mean it's as clean as i'd like with respect to separating inputs. I really doubt that more rear brake bias is necessary. More front spring would also do the trick. Not changing callipers until the suspension is in some form of tune. That'll come next year.

I will most likely not get the new LCA's installed for this weekend, but I will give it a try if they get done soon.

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 Post subject: Re: Autocross - The latest bit of fun.
PostPosted: Tue Jul 21, 2015 4:00 pm 
Somehow completely sideways in 4th

Joined: Thu Nov 10, 2011 11:43 am
Posts: 248
Location: Regina, SK
Great strory Craig - thanks for sharing all the details!

Reminds me of when I took my '76 Peugeot 504 to a 3 day race school in Gimli MB. It was great fun winning over the nay sayers which included some of the instructors, and really having a blast showing up much faster cars. (-3 degrees camber, 0 degree toe alignment, good brakes, sticky tires, and good driving being keys)

As for any advice I would offer: I would highly recommend getting the stickiest and widest R compound tires on your car before you start finalizing your set up. The extra traction they provide will totally change your car's behaviour and they really expose behaviors that you won't find without the added traction. It will also be your single biggest performance gain - bar none.

FWIW - I started Slaloming in the late 90's, and I've done pavement, rallycross (favorite), and road racing. Last few years life has gotten in the way, but I still love doing it and can't wait until I can get back at it. I've always run my RWD Peugeot's for events, and I've always done well - and that includes spanking AWD Subaru's in winter rallycross events in my RWD cars.

With the right tires and experience, I think you'll find your car will easily start rivaling the faster newer cars with ease.

Braking while turning? It's essential. Trailing brake to get the car to rotate an excellent skill to master, as does a touch of brake through the slaloms to get the weight to transfer to the front to get the car to turn in better under power as you go around the cones. Add left foot braking to your slaloms technique so you can keep boost up and eliminate lag in transitions cone to cone. Tough skill again - but it can save a ton of time if it keeps you in boost longer.

My only and biggest gripe with autocross/slaloms is that seat time is so short. By the time I've gotten into the groove your day is done! Rallycross and road racing offer much better seat time ratio's - but you're bang on with how technical and challenging it is.

Rabin


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