build diary

May 6, 2007:
I received an email today containing a comment I've seen a few times before, and it has to do with the troubles I have with my engine management when I change altitude.
The Link system I use doesn't usually have a problem with altitude changes, but I have two things about my car that makes it more sensitive than normal. First, my cams. I don't get a whole lot of vacuum at idle because of their overlap. Second, the throttle bodies. They make the car run in a very narrow range of vacuum. The end result is that when I change altitude - and that's not driving to the top of a hill, but 4000' of change - the range of vacuum my car operates in changes quite a bit. It's a problem that's particularly apparent with a Colorado car that has a tendency to travel around a lot. All of the Sevens on the cross-USA tour a couple of years ago were suffering badly from the change in air pressures - none of them had any way of compensating because they tended to run purely off throttle position.

A different ECU might be able to compensate better with a blend of throttle position and pressure sensing. Perhaps a bit more adjustability in the breakpoints in the fuel map would help as well. But it's always going to be hard to be my particular setup to behave with massive altitude changes. At least it's easy to change out the program in the ECU (providing I remember!) and it's a whole lot easier than messing with carbs.

I should also point out - in case it's not clear for those reading along - that the problems I was experiencing in Texas for the Car and Driver test had nothing to do with tuning. It was due to the broken PCV valve, something I didn't diagnose until I got back to Colorado.
entry 1367

May 15, 2007:
Time for a little more progress.
I've fitted the upper control arms from Kinetic to see how they work out. My thick spacers limit the amount of angle that can be reached by the rod ends, so the only way I can fit them right now leads to a loss in caster (fine with me) and camber (not good). I'm going to see if I can hunt down some different spacers or do a bit of grinding to regain a few degrees of misalignment. I might also shorten the front arm in order to improve the camber situation a bit more as well.
entry 1368

May 17, 2007:
I drove the car in to work today with the new control arms.
They're not an unqualified success quite yet. I've lost so much caster that the car is very twitchy. That's not so good. A bit of adjustment to the bushings and I can get a little more caster out of the setup, that should help. I've also lost steering lock as the new arms interfere with my fender stays. I'll find a way around that if the geometry of the arms works out.

It's kind of fun to be doing some development on the car again, not that I'm hurting for projects right now.
entry 1369

May 25, 2007:
Eric was in town for the weekend and got to see the Seven for the first time.
He's been a cheerleader of the project since I first started talking about it years and years ago - we've known each other about a decade now. He's seen the entire process, from my "Lotus fever" every Canadian winter, to the decision to finally do something, to all of the various problems and solutions that have come up during the build and tuning. It was great to finally give him the chance for a ride.
entry 1370
It's fairly easy to tell that Eric enjoyed his ride!
This was just a quick blast around the block, although my "block" takes about 10 minutes and includes a couple of decent curves. It's always a little frustrating to me because it's nothing like driving the car on the track, but Eric was laughing like a loon when we returned.
entry 1371

June 4, 2007:
It's autocross time again.
For the first time, I had another Seven to play with at the autox. The car - the FM Westfield demo car - is down on power compared to mine, doesn't have years of setup and Bill isn't much of an autocrosser. Doesn't matter, it's still fun to have someone to play with.

The course was a pretty good one. Not as fast as I'd like, but it's a narrow venue so there's not a lot of opportunity for high speed. There were three "turnarounds", cones that were basically the center of a 180 degree turn. This was a busy moment for me, as I was at maximum braking from the fastest part of the course, double-clutching down to first and (sometimes) pulling the handbrake. We all got 10-12 runs on the course, a hallmark of this particular race group.

Those with sharp eyes will notice that I'm running my old Falken Azenis tires. This is important.
entry 1372
On the course, I just couldn't get the Seven to hook up well.
Temperatures were nice and warm, but I either had the front end sliding or the rear spinning - sometimes both, of course. There was a real problem getting the front to grip on turn in. I was running on the Falkens instead of my usual Toyo RA-1s because I just plain ran out of time when loading up for the event. I didn't think it would be a major problem. But the car just didn't feel precise and it was smearing all over the pavement. On one part of the course this was a riot as I let the car swing around a series of four cones. But for most of the turns, it was a frustration.

We had a great race going on for the fastest time of the day. A turbo Miata, a well set up and unbelievably fast 1.6 Miata, an S2000 and the Seven all traded back and forth for the crown. The odd thing is that I've run with that turbo Miata before, and when I was driving a supercharged Miata we were very closely matched. The Seven is faster than that supercharged Miata, so why were we so close now? Heck, why was he ahead of me?

I spent a lot of time grumbling and grousing about my tires, and no matter what I did I just couldn't quite catch the others. I was running at the back of our little pack and had resigned myself to the fact that I just wasn't going to catch them. The fastest time of the day was a 1:19.185 for the turbo Miata while my best for the Seven was 1:19.881.

Just for fun, at the end of the day, I hopped in the Westfield for a run. Right out of the starting gate, I found what I'd been missing. The car leapt forward with that urge I'd been expecting from my car, and diving into the first gate was a revelation. Here was the front end grip and accuracy I'd been hoping for. The car didn't have enough horsepower to light up the rear tires so I couldn't steer from the rear at all. I didn't have the right shoes for its smaller footwell so I was a bit concerned about hitting the brake pedal which made me more hesitant. When I pulled into the pits after my run, I thought there was going to be a mutiny. I'd set a time of 1:17.435, about 1.7 seconds faster than anyone else. And it was all thanks to a good set of tires.

The RA-1 isn't usually viewed as a good autocross tire because it doesn't heat up fast enough, while the Falken Azenis is put up on a pedestal as the almighty champion of all. I'm not a big fan of the Falkens - too heavy and too stiff for my taste - and this proved why. Sure, the dedicated Hoosier race slicks will outrun the Toyos but you can't drive them up to the track. I don't think the Seven is ever going to leave the garage on Falkens again. Since the suspension is set up for the Toyos that might be part of the problem of course.

Nobody else got that Westfield around the track faster than 1:21.605. So it's not all tires!
entry 1373

June 5, 2007:
I mentioned Eric was in town last week, but I didn't mention why.
I got married. What sort of girl would marry me? The sort that thinks it's a good idea to use little Miata and Lotus models as cake toppers. Don't worry, we did have a real cake as well!
entry 1374
Another picture from last weekend's autocross.
I like the sense of speed in this one.
entry 1375

June 6, 2007:
There was one failure at the autocross.
Early in the day, the alternator stopped charging. It's always been a little slow to energize on startup. If I didn't give a bit of a throttle blip, it wouldn't light up. Well, the old one simply had enough. I spent the entire day - probably at least a dozen runs between myself and Bill - running the car off the battery. That little Odyssey is a tough little critter, it didn't show any signs of flagging at all.

I replaced the alternator with a new one last night and everything was much better. Okay, not new. Another junkyard alternator to replace the previous junkyard alternator.
entry 1376
The Seven has a very high-end car cover.
I'm painting some parts for the Targa Miata in my "paint booth" (aka plastic sheeting hanging from the ceiling) so I have the other kids covered up. HVLP paint guns don't produce a lot of overspray and the plastic traps it all, but I'd be pretty upset with myself if I managed to get overspray on the Seven!
entry 1377
This turbo Elise stopped by Flyin' Miata.
It's the first time I've seen Chrome Orange in the original application. You know what? It looks better on the Seven. Granted, I didn't get to see this car in the sunlight where the yellow pearl lights up, but it just didn't work as well as I'd expected. Perhaps a few more details like black wheels? It sure it eye-catching though!
entry 1378

June 18, 2007:
It's setup time!
The FM Westfield is going to be heading for some magazine tests in a month. That means it's time to get into high gear sorting out the brakes and handling. The Seven will be the benchmark of course, and it's in large part to the Seven's abilities that the Westfield got invited to play with the magazines in the first place. So I'm going to be a little busy.
entry 1379

June 27, 2007:
The Seven finally gets on the cover of a magazine!
Wired magazine?

Okay, I cheated. Wired had a special program where subscribers could get their picture on the cover of their issue, and I sent in a track shot. I think the fact that it's embedded in a "you are here" bubble is pretty funny - it's like they caught me speeding on a city street with a helmet on!
entry 1380
This super-sexy race seat is a Westfield part.
I've been considering installing a pair in the Seven to drop myself further down in the car and to save a chunk of weight. And also because they look soo gooood!

They're skinny, though. And expensive. I barely fit inside and I'm not sure I want to drop that kind of dough on seats when I already have a set. But just look at them!
entry 1381

June 28, 2007:
Well, the seats aren't going to work.
While the driver's seat fits nicely into my car, the passenger's side is much too small. It's probably just as well really. The price on those seats is eye-watering. And it's not as if there's little to do on the car.
entry 1382

July 9, 2007:
No Seven fun for a while.
As part of trying to sort out the handling of the Westfield, the Seven's rear springs sorta got borrowed. Sigh.
entry 1383

July 15, 2007:
Westfield development time.
I've been trying to apply everything I learned with the Seven to the Westfield. And I think it's working. The car is really coming together well. I've been at the racetrack a couple of times sorting things out, and on my first session in the "normal" direction, I pulled a 1:04.6. That's 1.3 seconds slower than my outright record! In a car with a (basically) stock 1.8, unfamiliar ergonomics (I'm still getting used to the pedals), no recent track time on my part and some sorting left to do. Outstanding! The car feels really good and has endless brakes, modeled after mine. I need to get mine to the track with good tires so we can do a back-to-back comparison, but I think Bill should be very happy with his Westie. One problem his car has that mine never did is cooling, although we were torture testing the car on purpose.

We're loading the Westfield up on my poor trailer and dragging it to Michigan so both Automobile and Car and Driver can have their way with it. I'll be on the road for over a week and kicking back in Ann Arbor during that time. Once I return, it's time to get the Seven back into shape (I want my springs back!) and then we'll have a lightweight car showdown!
entry 1384

July 25, 2007:
I spent the past week in Michigan with the guys from Automobile Magazine and the FM Westfield.
I got a chance to see Larry Webster again as well, it's always fun catching up.

Automobile tested the Westfield for performance numbers, and the results are interesting. It turns out Car and Driver (and most other magazines) subtract a "rollout" correction factor, basically removing the time it takes for the car to move the first foot. I'm not sure why, perhaps it removes some of the variation between testers. Automobile does not.

The Westfield was fitted with a 1.8 Miata engine that was stock internally and I'm going to guess it's making about 110 at the wheels. That's down on my car, but it also should have more torque. The 0-60 time was a half second slower than my car. The braking was about 15' longer, probably due to different proportioning. Since the Westfield was tested on a proper skidpad on the Bosch testing grounds (as opposed to a small dusty parking lot at a Texas dragstrip), lateral acceleration was a very strong 1.15g. The interesting bit is the quarter mile, though. The elapsed time was a half second slower, but the trap speed was within a couple of mph. Meanwhile, my car was a full 2 seconds faster to 100 mph. That doesn't make much sense to me, but I'm not a drag racer.

There's a track day this weekend and I'm considering taking the Seven, but I think the recent push to get the Westfield finished and the 3000 mile road trip has me too tired. Besides, my rear springs are on the Westie and I'm not going to get them back until next week! But then it's time to get the Seven on the dyno and into top shape, it's going to be quite a battle for the lap record at the Open House this year. Not only will the Westfield be chasing, I'll have a turbocharged Caterham to deal with.
entry 1385

July 30, 2007:
Trackday time!
We're having a company track day on Thursday - one of the perks of working at a place like Flyin' Miata, although I must admit that spending four days planting subliminal messages in the boss' brain while driving to Michigan and back probably didn't hurt. Of course, my idea of "subliminal" is "Hey Bill, we should have a company track day".

This will be the first chance for the Seven to truly chase the Westfield around the track. Well, it will be if I get my rear springs back and manage to finish painting the Targa Miata in time so I can get the Seven out of the garage. Some work lies ahead.
entry 1386

August 1, 2007:
The springs are back!
Bill returned my springs after installing a truly drool-worthy set of Nitron shocks on the Westfield. He also handed over the Westie's original shocks - that's the black one. I'd heard they were made by GAZ and the construction certainly backs that up, but notice it has more travel both in extension and compression. Nice! I don't really have any droop travel right now thanks to the stiff rear springs and the ride height I'm running, so I figured I'd install these instead.

Alas, it was not to be. Turns out the bushings are sized for a metric bolt, or at least a smaller bolt than I used. Nuts!

The track day tomorrow should be fun, but I hope I can play for a significant period of time. One of my RA-1s took a lot of wear when I ran it on the track on a Miata and it's starting to cord on the edge. I really shouldn't take it out at all, but I'll monitor it closely. At least it's a slow track! Or I could just take the Mini instead, but that means I can't chase the Westfield...
entry 1387
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