build diary

October 4, 2005:
Reading over what I did to try and set up the car this weekend, some of it sounds backwards.
The tire pressure changes were based on reading the tread. Given the length of the track (a "session" was only 5 miles!) it's possible they only barely reached full temperature. Lester Seal reports that he is running much higher pressures on his RA1s on his car and I'll start off there when I'm at Aspen in a couple of weeks. The real opportunity for tuning will come at a Pueblo event in a month. Hmm, maybe I should hunt down a pyrometer for this. I really need to get the suspension sorted. Lester reports he is running much less camber than I am.

Naturally, there's work to be done before the next track day. The car ran well - flawlessly, actually - but I still have to sort out the hood. I'll try to get a start on that tonight.
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One of these cars is a visitor to town.
Guess which one.
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My first hot laps at the Octoberkross event.
Still lots of roll here and I'm having trouble getting the front wheel to stick.
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By contrast, the left turns are nicely balanced.
This photo was taken later in the day, after I'd added a touch of front camber to both wheels and removed the windscreen for a bit less wind resistance and a big psychological shot at my opposition. That rear wheel looks questionable.
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I managed to sort out the understeer - this is the same corner as the picture taken earlier in the day.
This attitude was no slower than the grinding understeer but it sure was a lot more fun. The black stripes on the corner are from the previous lap.
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Gratuitous? Not me.
Never. This is a different lap than the previous picture. The best part is that the tail was still coming out but the next photo in the series didn't turn out.
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During the fun runs at the end of the day, I was harassing this Neon.
I figured he'd enjoy the view more if I gave him something to watch. The best part is that the owner of the Neon is riding with me...
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October 5, 2005:
Well, no progress on the hood.
However, I did spend some time looking at mufflers. Between seeing all the Se7ens on the tour, running my car for a few hours on the road and again on the track with the Supertrapp tip, I've decided it's time to make the car quieter. All the "real" Se7ens run much larger muffler cans, enough that my little resonator looked pretty funny. So I wandered over to the Summit Racing website and started looking around. I've spent lots of time looking through their print catalog but the site amazed me. I was able to set my requirements (2.50 inlet and outlet, centered, round muffler, etc) and it weeded out all the hundreds of options I didn't need. By the end, I was looking at a list of 7 mufflers with full dimensional diagrams and a size range from 4"x14" to 6"x27". It couldn't have been easier - thank you Summit! I'm assuming that pretty much any 2.5" muffler will be able to flow enough air for my approximately 170 crank hp without noticeable restriction, but I'll see if I can find flow ratings for them. I'll do some measuring tonight to see what will work. It's a real shame that mufflers are sold with such vague descriptions - do I want an "awesome full throttle sound", a "deep aggressive tone", an "old school glasspack sound" or just "excellent sound"? I know I don't want a nasty rasp but none of them say that. It'll be a shame to lose some of the crackles and bangs but right now, wide open throttle hurts without the Supertrapp tip or ear protection.
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October 6, 2005:
Ben from Caterham is bringing his SV (the red one in the Moab pictures) to the track day at Aspen.
Oooh, the moment of truth! I think he's running an extra 30 hp or so, but I really want to know how it compares on track. This will be very interesting.

To help make the car faster, I've found a care and feeding document for the RA1. Interesting stuff. This will come in handy in Aspen and I promise to do some real setup. The first step will be to dial some real camber into the car because the RA1s like lots of camber. I'll probably also toss in some thicker sways to keep it flat. As for the exhaust, I had a good chat with Chuck at Thermal R&D. He makes the exhausts for Flyin' Miata. I'm going to send him some photos and a list of what I need and he'll come up with something. He does beautiful work and his systems always sound great.

The results are posted for the track event. No surprise that I'm on top - I knew that already - but I was curious about some of the others. The closest competition is a quarter of a second back and there are a fair number in the 1:06 range. I'd better get this sorted out!
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October 9, 2005:
I've finally put up some more photos from the track day.
I'm such a sucker for photos of my car although they do provide some interesting analysis. That's my justification.

The Seven did get some attention today (finally!). The Aspen track day is looming in a week so I want to be ready. The first step was to make sure I had enough camber in the wheels. Unexpectedly, I had quite a bit. My memory of my specs wasn't even close. The rears were at 3.4 degrees negative camber and the fronts were about 3.1 (R) and 4.3 (L). The massive amount of camber on the LF is from the recent track day from trying to keep it planted on the rights. A quick check of toe made the cause obvious, though. The RR tire had about 1/8" toe out. That would have rotated the rear nicely (to put it mildly) on the left corners and made up for having too much front roll stiffness, relatively speaking. The right turns were probably illustrating the current balance of the car. I dialed the toe out of that corner, leaving me with about 1/16" toe out in back (I know, that's bad) and put a stiffer sway in the rear. Depending on how the Aspen day goes, I can easily dial out the remaining toe and also use the adjustable bar to add more rear roll stiffness. I'd like to put a stiffer bar on the front as well. I jacked up the LR a bit as it was riding about 1 cm lower than the right side with a driver, then evened out the corner weights. Oh, and the car now weighs 1328 lbs with a mostly-full tank of gas. I've decided the best way to improve performance is to take weight out of the driver. It'll balance the car better, you see...

While I was underneath, I noticed a small gap between the rear upright and the lower rear control arm. The upright was free to bang back and forth under acceleration and braking! I can't explain how I missed this on assembly, but it's been shimmed up now. Yikes, that could have ended badly. That explains a clunk I'd heard a couple of times last track day.

I have noticed that I'm much more sensitive to the car now. Carrying a passenger makes it almost undriveable on the track where I used to find it perfectly acceptable. Even taking a 100 lb girl out for a few laps made a noticeable difference in acceleration and handling.

Next work: the hood then the exhaust.
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A front shot from the morning timed session.
I dialed in just a touch more negative camber after this one.
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Still a fair bit of body roll, although that front wheel is climbing a berm and I'm hard on the throttle.
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Whoops.
Too much front brake bias!
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The Seven is starting to look a little mean when parked.
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Talking to Janel after one of her sessions.
No, this photo doesn't belong on the Seven site. But she did well at the track!
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This is a fun shot.
The car's obviously not going straight...
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I think this is one of my favourite action shots of the car ever.

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The lower rear control arm where it meets the rear upright.
Why didn't I notice this gap earlier?
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A new adjustable rear sway bar and a lot of Moab mud.
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October 10, 2005:
Nope, no work on the hood yet.
After dropping off that larger sway bar yesterday, my coworker Mark was looking at the Seven. It's the first time he's had the chance to really examine it. He noticed a bit of brake fluid at a front junction so I tried to snug up the fitting. Turns out it was another of those dumb versions with the unthreaded "nose" so it was only barely hanging on. Luckily, it was also on a portion of brake line I'd been intending to reroute anyhow. It also managed to be the perfect length of a piece of off-the-shelf brake line in the new orientation. Ahh, an easy fix. Now I just need to bleed the front brakes, then take the car home for some hood fittin'. Thanks for the sharp eyes, Mark!
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October 12, 2005:
Well, the hood has finally been started.
I haven't been able to find my original hood template and I just wasn't getting around to buying the cardboard to do it again. Finally, whilst standing in my garage and lamenting the fact that I needed to go shopping, I spotted the familiar black/green/yellow/blue hues of my template. It was stuck behind some spare parts and rolled up. Some comedy ensued as I tried to lay it out flat and then discovered that my new piece of aluminum was about 3/4" too short according to the notes I'd written on the template, but I won in the end. The aluminum has been cut to a rough shape and now I have to bend it to fit the car. Instead of simply wrestling it into submission on the grass like last time, I'm going to anneal the aluminum and see if I can be a little more precise. I should finish tonight and then it will go in for louvres in a more appropriate direction. The fun never ends!
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Aluminum cutting and bending fun - it's time for a new hood!
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