build diary

March 11, 2007:
Another track day - but this one wasn't in the Seven.
Instead, it was the debut for the Flyin' Miata Westfield that I've been working on. The engine fired up last Sunday, the car moved under its own power for the first time on Thursday, so the obvious thing to do was to take it to the track on Saturday. Less than a week from the first noise to full throttle down the front straight? Of course.

The car was amazingly good out of the box. It's very comfortable to sit in. There are no squeaks and rattles when driving around, and the suspension does an excellent job of suspending. Amazing. We did have a few little teething problems such as a clunk in the front suspension and an odd behavior caused by a short in the engine management computer that was fixed by removing the backside of the case, but by the time we'd had lunch it was up and running happily.

So, how does it feel? Not bad at all. The steering (the optional quick rack) is very well done and the car responds pretty well to anything you ask. The front track is narrow relative to the rear and Westfield recommended very little front camber, and the result is that hard cornering is ruled by the need to get the front to stick. This means a more cautious approach to entering a corner to make sure you've got front-end grip, and the balance in fast sweepers is dictated by controlling understeer. With some shock adustments and a slight 10mm bump in front track, it got much better. We're going to dial in a bit more front camber (it's currently at about 0.2-0.3 degrees negative) to see if we can get some bite. Westfields are known for handling like this from what I understand, but it could be improved. It didn't stop me from hanging out the tail in a couple of corners and from obtaining a fairly neutral stance in the fast turn 1 sweeper. It just took a different driving style than in my car.

There's also the matter of the brakes. I don't think the rears are contributing much at all and the right front wheel locks fairly easily. We'll do some cornerweighting to the car and see if I can adjust the proportioning front/rear somehow.

Overall, Bill and I are very happy with the car. The two of us went out to play and found that the car was very closely matched with Janel's little Miata. The 1.6 Miata has a supercharger (about 150-155 at the wheels, I'd estimate), upgraded suspension and my poor abused Toyo RA-1s. The Westfield has a bone stock 1.6 with a Link ECU for engine management (perhaps 95 hp) and my old set of Falken Azenis RT-215, a slipperier tire than the Toyos. The Miata is very well sorted, the Westfield had only just come off the build stand. I think there's good potential there.
entry 1348

The Westfield is alive! It's a great looking car once all the body panels are on, and it works very well right out of the box.
entry 1349
They're so pretty when they haven't even been wet yet.
This is a stock engine that's simply been cleaned up.
entry 1350

March 15, 2007:
At the track in Texas.
Burt "BS" Levy (author of The Last Open Road, I'm sure he'd want you to buy his books) gives his feedback on the Seven. Here's what he had to say in a later email:
REALLY enjoying your book, and now understand why the blessed car works so well. You have a wonderful practical grasp of balance, weight transfer, bump steer, etc., and the car sure shows it.

Am I bragging? Sure, why not. Thanks to David at Grassroots Motorsports for the picture.
entry 1351
Racing furiously down the front straight...or a staged picture for a magazine? You decide.
Bert is in the Atom while Tim Webb drives the Seven. What did Tim have to say?
I just wanted to drop you a note of thanks. I appreciate you letting me drive your very well prepared car. It truly was a joy to drive. I drive lots of cars and other than my FF1600, I don't get to drive such well mannered "street" cars....
Again, thanks. If I didn't have a racecar, I would seriously consider a Locost.

Okay, enough of that. Thanks again to David at GRM for the picture.
entry 1352

March 20, 2007:
While I've been patting myself on the back, the Seven has been sitting disassembled in the garage.
I'll take the head to the machine shop tomorrow and see if they can figure out how to get that lifter free - if it's possible. If not, I'll give them a spare head to work up. I might even stick a stock head on the car to make it drivable again.

In the meantime, it's time to get some serious work done on the Targa Miata.
entry 1353

April 6, 2007:
I've decided to install a stock head on the car.
The porting on the previous one was "nothing special", according to Bill. So I just need to pop in some valve springs and swap the cams. I have the head already, it's from a 323 GTX. The way things are going with all the other work I'm trying to get done, it's tempting to simply swap the cams out and deal with the springs later. But I made that decision once before, and look where it got me.
entry 1354

April 12, 2007:
I was driving to work yesterday and I was a bit ahead of schedule.
What the heck, the Seven's damaged head was in the back of the car and I was going right by the machine shop. So I pulled in to see what they had to say about my jammed lifter.

They had good things to say! Joe - the machinist - figured there was a good chance he could get it out. I left the head and went on to work. A couple of hours later, I got a phone call saying the lifter was out and that nothing was damaged other than the lifter and the valve. No worries there, they're littering the place. While installing my new springs, he also found that all my other lifters were showing really odd wear patterns from constant valve float. So he replaced all of them with the set I had pulled aside for the Targa Miata head.

As I might have mentioned, I had the redline set a little high so I could stretch out one of the short chutes at the local track. Down in Texas, I think Burt had been leaning a little harder on the limiter to stretch a longer straight and the abused valvetrain just gave up. Well, I had told him it was safe to work the car hard.

At lunch I stopped by to pick up my repaired head - one new (used) valve, 16 new (used) lifters and a new (new) set of valve springs. The used parts came out of the piles of spares that are sitting around at Flyin' Miata and in my garage. That was faster and easier than I'd expected!
entry 1355

Back in December 2004, I had the head off the car to fix a problem with the pistons and I considered installing new valve springs to handle higher RPM.
At the time, I decided against it. If I hadn't, I probably wouldn't have suffered a failure at the track in Texas. So I'm not making the same mistake twice. Aluminum seats, titanium retainers and a reasonable $366 retail price. Not bad really.
entry 1356
Preparing the block for the head.
I have to start using multi-layer steel head gaskets on this engine. I'm getting sick of cleaning off the remnants of the composite ones! This is at least the fourth head gasket to go on this engine thanks to the various rebuilds. It should be good for years of hard service now though.

If you look carefully at the exhaust valve cutouts, you can see where the valves were hitting the pistons. I didn't see this the last time the head was off, so the float was obviously extreme recently despite the same redline. I cleaned up the pistons with a dremel to take the sharp edges off and some fine Scotchbrite soaked in carb cleaner removed the carbon. Cleaning the headgasket was done with a plastic scraper and a Shop-Vac powerful enough to lift carb cleaner right off the head. No metal shavings in here! At least, I did my best to avoid it.
entry 1357
The Seven and the Targa Miata, in a race to see who gets on the road first.
Given that the Seven now has a head and the Targa car doesn't even have pistons in the block yet (tonight it will!), it's probably best to bet on the Seven. Soon I'll be able to get back to testing those new control arms.
entry 1358

April 16, 2007:
It's alive!
I installed the new head for the second time, and... second time? Yes, I'd pulled the head off in order to verify some questions about the new valve springs. So it's back on and the car fired up happily. Excellent - now I can drive! Which means, of course, that it rained today. The Seven hasn't lost its magic.
entry 1359

April 19, 2007:
The June 2007 issue of Grassroots Motorsports has an article on "15 tips to Locost success".
I think it's brilliantly written and insightful. Careful observers will also notice that it is illustrated with many pictures of my car and that I wrote the article.

If you're interested in a free copy, just stop by the GRM website and ask.

The Seven is also featured on the front page of B.S. Levy's website along with the Atom.
entry 1360

April 30, 2007:
At long last, the Seven meets the FM Westfield.
We took the two cars down to Moab to check out the car show there. It was a sunny, warm day that was perfect for a road trip.

It's really interesting to see the cars together for the first time. We didn't spend a lot of time standing around looking at them, but you can see the differences in scuttle height and placement in this picture. I didn't have the ECU in the Seven set up for high altitude after the trip to Texas, so I was down on power a fair bit - this made the cars fairly evenly matched in a straight line until the Seven could clear its throat at around 5000 rpm.

The biggest difference was in the suspension. The Westfield is much softer than my car and rides incredibly well, but I could see it running out of travel once in a while. I'd brace for the bump and the Seven would just drive right over it without any trouble. Bill turned up the damping a bit to compensate (he was running with two people, as was I) but I haven't heard what sort of difference that made.
entry 1361
Now this is why I built the Seven.
This, plus fun on the racetrack. It's easy to get the impression that the car is almost exclusively a track trailer queen, and it's certainly doing a whole lot of that. But it does get out to play once in a while, and it's good at playing. The difference is that on the road, I don't get to push things much. There's a whole level of the Seven's performance that can only be accessed on the track. The first time Janel rode in the car on track, her impression of the car changed dramatically - she had no idea of the rabid hard edged performance that was hidden inside.

Naturally, Bill and I had a bit of fun on this road. It's about 40 miles of twists and turns and I know it pretty well. We had traffic on the way in to Moab, but we got a pretty clear run on the way back. For some reason, the Miata that was also running with us took a bit longer to get to the end of the road.
entry 1362
Bwaaaaahhhhhh!
entry 1363
The Seven now has a stereo.
It's great for longer trips, as it cuts down the noise from the exhaust and wind as well as keeping the driver entertained on the highway. The little Shuffle clips on to the harness so it's both easily accessible and out of the way. This was a birthday present from Janel, and it's no coincidence that it matches the Seven!

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
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