build diary

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.
entry 1043

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!
entry 1044

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.
entry 1045

A front shot from the morning timed session.
I dialed in just a touch more negative camber after this one.
entry 1046
Still a fair bit of body roll, although that front wheel is climbing a berm and I'm hard on the throttle.
entry 1047
Whoops.
Too much front brake bias!
entry 1048
The Seven is starting to look a little mean when parked.
entry 1049
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!
entry 1050
This is a fun shot.
The car's obviously not going straight...
entry 1051
I think this is one of my favourite action shots of the car ever.

entry 1052
The lower rear control arm where it meets the rear upright.
Why didn't I notice this gap earlier?
entry 1053
A new adjustable rear sway bar and a lot of Moab mud.
entry 1054

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!
entry 1055

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!
entry 1056

Aluminum cutting and bending fun - it's time for a new hood!
entry 1057

October 14, 2005:
So, what's up with the hood? I was trying to motivate myself to get into the garage to work on it on Wednesday night.
Then I remembered that this car stuff is supposed to be fun. So I turned my back on the garage and did something else. I'll just have to run with a backwards hood at the track.
entry 1058

October 17, 2005:
My advance copy of the book arrived on Friday!
It looks great. Watch this space for availability.

Saturday was the track day at the Aspen Sports Car Club. This is a private track with dues and costs that are in line with what you might expect from one of Colorado's areas of fiscal unreality, but I guess I can understand it more than a high-buck golf club membership. The track itself has a reputation for being unforgiving if you go off - talk of "safety boulders" can be heard - but the reality isn't quite as fearsome as that. Yes, there's nowhere to go but a deep gravel pit and a tire wall if you have a real problem at the end of the straight, but on a track day there's nothing wrong with leaving a little margin for error. The track itself has a lot of character and an fun rhythm with a couple of corners that require quite a combination of technique and nerve. It's a much different track than the kart track I've been on recently despite being about the same length. I can see how it might be a good one to drive for years - there are enough challenges to keep it interesting.

So how did the day go? Well, it was eventful. We left early in the morning and towed the Seven up to Aspen. The car then refused to start, fouling its plugs immediately. Since I was "close" to home I hadn't brought along a full set of tools or spares, but Bill let me steal a set of plugs from one of the Miatas to get the Seven running. Once it was happy, we put the fouled plugs in one at a time and eventually had a happy car. I went to familiarise myself with the track and discovered the car was very upset at full throttle below about 6500 rpm. A quick peek at the computer display for the engine management showed me it was running really lean. When I'd tuned the car in Grand Junction on the dyno, we hadn't spent any time on the areas just below full throttle. Thanks to the high altitude and low air density at the Aspen track, these areas were now full throttle. I pulled into the pits and we hooked up the laptop. 2 minutes later, I headed back on to the track with a transformed car.

After a couple of sessions to learn the track, we did a quick tire temp check. I'd tried raising the pressures after seeing Toyo's recommendations for a 38 psi target, but the numbers were much too high in the middle and it was obvious that I really wanted something lower. A big thanks to Ben from Rocky Mountain Sports Cars for taking the pressures and temperatures for me. We then saddled up and went out to play.

Ben had brought the red Caterham SV that I saw in Moab. It was fitted with a Zetec engine from the SVT Focus. It's rated for 200 hp. Weight is apparently similar to my car. The tires were Avon CR500's that were getting a little tired and the car was set up for street use. How did it compare to my Seven? I was happy to see that our acceleration wasn't really any different on the straights - hmm, one of us has our power output wrong. Ben's a Formula Ford driver and was definitely quicker through a few sections, but between my tires and better brakes I was able to keep him in sight as long as I didn't make any mistakes. He'd gain a couple of car lengths per lap, mostly through one corner that was particularly technical. We had to deal with a fair bit of traffic on the small track though, as we were travelling pretty quickly. One other driver commented, "I expected them to be fast, but not THAT fast!" after we double-teamed him on the straight as if he was parked.

The Seven did pretty well. I'm starting to wonder if there is any camber change in the front suspension because it's still working the outside of the front tire even with more than 4 degrees of camber. It's also rolling more than I'd like but the balance is excellent. The car would oversteer or understeer depending on how I was driving it. The corner in front of the pits was particularly well suited to hanging out the tail so I had a little fun with this. Ben though it was entertaining to watch and was impressed that I was able to control it well - there's the advantage of growing up in the snow. If I was trying to go fast, I could whip around the corner with a very neutral balance. There was one small problem as the brakes started to drag when the car got hot. There wasn't enough free play in the brake pedal so as the fluid expanded, there was nowhere for it to go. I fixed that quickly by adjusting the master cylinders and I'll insulate the new brake lines better. I was feeling good. Then I made a mistake.

Coming in to turn 3 and playing with lines, I let the back end walk out a bit. This set me up to run right over the cone at the apex. No problem, I've done the same at autocrosses. This time, however, the cone came off the front tire and slammed into the rear fender. I thought at first I'd caught the cone under the car, but a look at the car in the pits made it obvious I had ripped the fender halfway off the car. The damage wasn't too severe but I couldn't keep driving like that. 5 minutes later, I had the fender off and went back out - I was smart enough to put quick disconnects on all the light wiring during the build process. The car felt a little uncertain with the right rear tire loaded up until it all of a sudden started feeling flat. Halfway back to the pits (crawling along in first gear) I realised that I'd forgotten to torque the lug nuts due to my distraction when working on the car and talking to people. A stupid mistake, especially considering that I'm usually quite anal about the lug nuts. No damage done other than to my self-image, I headed back out.

Bill Cardell was out in the Caterham as a passenger this time. We had a huge amount of fun playing around with Ben still gaining slightly on me every lap. Bill then jumped into the driver's seat and we played a bit. His feet didn't fit the Caterham pedals properly and it wasn't his car so he wasn't as fast as Ben had. Still, we came in just giggling from the fun of chasing each other around.

Overall, a good day even if I'm left with some repair work. I didn't do all the testing I'd planned and I suspect I'm going to regret that shortly. It was really good sharing the track with Ben as well as the usual Miata folks. Bill and Teri from Flyin' Miata were there with a couple of our very fast Miatas, one of which was just bursting with horsepower. It was the only car that could outaccelerate me down the straight but we were turning equivalent track times on the same rubber. Janel had a chance to try the Seven on the track and her "just a couple of laps" turned into about 15 as she played around with it. At the end of the day, Bill and Teri took the Jeep back to Grand Junction as Janel and I drove the two high-speed Miatas, both of whom have been in Car and Driver at some point. Ah, it's a rough life.
entry 1059

The Aspen track isn't a big one, but it's a lot of fun.
entry 1060
It's not that my car has evil handling tendencies, it's just that driving like this is so much fun!
Besides, the pictures look cool. The runoff behind me is where you end up if you lose your brakes on the straight.
entry 1061
Playing with Ben and his SV.
entry 1062
Once in a while traffic would get a little bunched up, but it was easy enough to pass.
But check out that view! Yes, that's snow in the middle of October as I drive in a t-shirt.
entry 1063
I fought the cone and the cone won.
I have a little work ahead of me but there should be no major cosmetic damage with a new rock shield and a bit of 'glass work.
entry 1064
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