build diary

October 3, 2007:
The new issue of Grassroots Motorsports has arrived at subscribers.
This is sad, because it means that the Seven vs Atom article is now old news. But it's happy, because I've been given permission to put the article online! Now it can live on. Note that it may take a week or two before the new issue arrives on the shelves, so if you want a hard copy you can still run out and get one.
The article can be downloaded in PDF format. I have two versions, a small one that downloads quickly and a big shiny one that has better quality pictures - not that you can tell a difference on screen.
Small file (878 KB)
Large file (2.04 MB)
I'm proud of this.
entry 1404

October 14, 2007:
Autocross time again!
Somehow, despite running my own autocross series all through the summer, I never got around to taking the Seven up after the big tire debacle of the first race. So it's been four months. It feels like a whole lot longer, honestly. I've spent so much time working on the development of the Targa Miata that the Seven has been sorely neglected. So I put out a little extra effort and managed to get both the Miata and the Seven out to the final autocross of the season, run by my friends at the Corvette club.

Driving over to the venue, I was reminded just how different the Seven feels than the door slammer. The chassis isn't as rigid (the Miata has a full cage) but the suspension is stiffer (the Miata is a rally car, remember). It's the immediacy that had dulled in my memory. I'd be concentrating more on the problems of late - poor tires, cooling fittings that were cracking and spewing - than the ability of the car.

I started off driving the Miata in the first group - you can read about it on the Targa page. This meant that when I rolled up to the start line, I had an idea of the course and a target. Target? Oh yes, the Fiat was in town.

We met up over two years ago and the Seven was vanquished by a 0.3 second margin. We've run against each other on the track a few times, but I have not had the chance to avenge my autocross defeat, as that's where the Fiat is at its best. I was on a mission. I've made a lot of improvements to the car since that time, but never had a chance to prove it until today.

On my first run, I was blown away. I'd forgotten how violent the Seven could be on an autocross course. Even though I'd put down the second fastest time of the day (to that point) in the Miata, the Seven was far ahead of me and I was just reacting to it. The first run was, shall we say, messy as I collected a couple of cones and spend a lot of time trying to keep the tail in line. The cold weather didn't help, but it was mostly just me trying to adjust to the ferocity of an uncaged Seven.

On the next couple of runs, I started to get on top of the car. My second run put me ahead of the Fiat, and I concentrated on cleaning things up. Finally, on my fourth run I put down a clean lap and figured I had my fast time. Then, on run five I tried a different line - one I'd spotted during the course walk but this time I exaggerated it and combined that with an even cleaner run. The result? Another 0.9 seconds off an already-impressive time. My last run was a DNF as I overcooked the entrance to the slalom, but I parked feeling pretty happy.

The Fiat had three runs to respond - it was an odd run grouping. He tried, but didn't manage to improve over his best time set earlier. The final margin? 3.231 seconds. This was FTD, and the Fiat was second-fastest with a well-driven C5 Z06 very close behind. I think I redeemed myself from the previous loss a couple of years ago. Now that's what I wanted. Not just a victory, but domination. Over 3 seconds on a sub-60 second course.

The Seven wasn't completely unscathed. Yet another cooling fitting let go - a little rubber cap on the back of the head split and started misting the scuttle with coolant. It's the exact same failure I had last time at the track, but this time at the rear instead of the front. Luckily, this is the last of those rubber caps so I should finally have this series of foolish little problems sorted out. I drove home with a big smile and little drips of coolant on my feet.
entry 1405

October 23, 2007:
Rob Mitchell is a fan of the Seven, and he sent me a little present for it.
This oil warning light is just perfect for the car. Thanks so much, Rob!
entry 1406

October 31, 2007:
The Seven is trapped in the garage.
The Targa Miata is awaiting a new suspension, and I brilliantly took it apart while parked in front of the other toy cars. So I'm stuck driving my old Toyota pickup until that suspension arrives.
The Targa car is getting new parts in preparation for a track day at Pueblo. It's the third anniversary of the first big track day for the Seven, but unfortunately logistics prevent me from bringing both cars. It's frustrating. I need to build a two-car trailer!
entry 1407

November 4, 2007:
I went to the Pueblo track day without the Seven, but that doesn't mean I didn't get something out of it!
The Targa Miata was there and that was my main focus. Bill brought along his Westfield (using the same trailer I did three years ago) and I had the chance to do a few laps in that. Janel also got a chance to drive it, and had some interesting comments. I felt the car was working well from a handling standpoint - it was faithful and adjustable, with the fast reflexes you expect from a lightweight. But the engine doesn't inspire. It's a fairly stock 1.8 with good engine management. This gives it great throttle response and it does outgun my car in terms of torque, but it's not inspiring. Both Bill and I agree that it doesn't have the top end it needs. My best description is that it doesn't howl. Bill's working on that, and hard. So for the moment, it's simply very competent but it doesn't have that edge it needs.
Janel took the car out for a fairly extended tour. She did enjoy driving it, but found that there were a few things she preferred about the Seven. The most obvious was the brakes. The Seven has, if I do say so myself, exceptional brakes. The Westfield has a less reassuring pedal. Is it due to a flexing pedal box, a mismatch on hydraulic sizing and pedal ratio (quite possibly considering the lack of understanding apparent in the original clutch hydraulics on that car) or a problem with the donor parts? I'm not sure, but it does take some getting used to. The Seven also doesn't roll quite as much and is a little less biased towards understeer.
So there's the target - make the Westfield feel like the Seven. On the way home, I started to make plans about putting a bike engine in the Westfield. It could be quite a killer!
entry 1408

November 28, 2007:
There's an unbuilt CMC "Miata" frame on eBay.
It's the same thing I started with. I'm amazed it's surfaced, but then again I did hear of an unbuilt 1977 Caterham in the Denver area yesterday.

I'm interested in the background story of this kit. The seller says that CMC went out of business around the time he took delivery, but the design of the rear control arms is an earlier one that was used before Heikki's car was built - I think that's the case, anyhow. Perhaps it's one of the frames that went through a dealer. The interior panels are more complete than mine were. However, the scuttle is missing. More importantly, so is the MSO which may make it difficult to register.

Still, for anyone looking for a starting point for a Seven here's a good option. There are a few things to fix up - the rear differential mount comes to mind immediately - but readers of this website won't have trouble figuring that all out.

eBay auction
entry 1409

December 29, 2007:
We've had a nice, wet and cold December.
So while the skiing has been fantastic, the small sports car fun has been curtailed. The Seven has been moved to the back of the garage to make room for more pedestrian vehicles - the garage is two cars wide but 2.5 cars deep. To make it easier to shuffle the car around and keep it out of danger, I picked up these very high-tech toys. They're moving dollies from Harbor Freight and can carry 1000 lbs each. Not bad for $10. We have some fancier ones at work that are a lot more expensive, but this is all I need...
entry 1410
Since I'm working on the exhaust for the rally car, I've become inspired to work on the one for the Seven.
Remember those motorcycle mufflers I picked up aeons ago? Well, one of the reasons I haven't installed them is because I'm sick of cutting up the exhaust again and again. But I have a spare header collector, which means I can build a new setup without having to destroy the old! Time to get to work then.
entry 1411
And here I was being so clever.
The new collector is actually much better than the original one. Unfortunately, it also puts the pipes slightly further apart. This doesn't play well with the inflexible header pipes.

Now that I know more about collectors, I'm pretty sure my original one is a formed weld-on unit with some tubes welded on the end. They're inexpensive, around $35 new. So maybe I'll order another one. I prefer that idea to the alternative of messing with the header pipes!
entry 1412

January 2, 2008:
I was wrong about the price of the collector.
It's not $35 each, it's $35 for two! So I'll have lots of parts to play with then. This will make 4 collectors bouncing around the shop right now.

Last year I took the Seven out for a drive on New Years Day. This year, I went snowshoeing. It's not a friendly year for little sports cars yet.
entry 1413

January 8, 2008:
The new collector is here.
It's obviously a $17 piece. I think I can make it work, but it's certainly not going to just slip on. Bummer. I have some other ideas that might work though. Watch this space!
entry 1414

February 4, 2008:
There's not much action going on with the Seven right now.
We're seeing record-breaking snow and the car is being neglected for the Targa Miata. That's the car I'm building for the Targa Newfoundland, and I'm using a lot of the techniques and skills I learned on the Seven build - such as building a very complex header.
If you're looking for updates, you're probably better off watching that site for the time being.
The Targa Miata
entry 1415

February 28, 2008:
Caterham has announced the uberSeven - an SV stuffed full of an RST V8 and a supercharger.
The headline number 1000 hp per tonne, although I suspect the weight and horsepower numbers have been massaged a tiny bit to get that magical fourth digit. Still, even at 900 hp/tonne it would be quite a ride.
The Caterham Seven RS
What about my own little car? Well, as predicted, it's been sadly neglected for the Targa Miata. I promise to get it out for the upcoming Corvette autocross at the end of March, though. It's time to stop trying to alter the car and time to just take it out for a blat once in a while.
entry 1416

March 11, 2008:
I spent Sunday at the track.
No, I wasn't driving the hibernating Seven, I was testing the Targa Miata. But I did get a chance to drive the FM Westfield. This car's shown up here a few times and it's turned into a real sweetheart on the track. It has a slightly different character than mine but it's still a ball to drive. Well, Bill spent last week sticking a turbo on it and it now makes somewhere around 250 hp at the wheels.

Does this make the car an unguided missile? Far from it, the chassis is fully capable of dealing with the power/weight ratio. The straight line speeds is, as expected, ridiculous. But the friendly handling remains, and the car eggs you on to push harder and harder like a good Seven should. It only took a couple of laps to acclimatize myself to the car, despite the fact that my last few track days have been in a Miata with relatively soft rally suspension. Soon I was playing with power oversteer in fast sweepers and prodding at the car's limits everywhere except under braking.

It was a completely different beast from the Atom. Where that car was edgy, this one is friendly. And inspiring. I'm trying to think of what I can do to my car to take it to the next evolutionary step...
entry 1417

April 5, 2008:
Well, it was going to happen eventually.
My lap record from April 2006 fell today. The old record of 1:03.777 (clockwise) was blown away as Bill turned a 1:02.455 in the Westfield. Remember, the car's turbocharged now so the distance between the corners is a whole lot less! I got the chance to drive the car on the track - a much tighter one than Pueblo - and it's a bit more of a handful in the smaller venue. Catching power oversteer at 70 mph in the middle of that downhill sweeper made for an exciting ride.

Luckily, Bill wasn't quite able to match my 1:02.471 running counterclockwise, having to settle for a 1:02.807. Not too shabby, and with a little more seat time and some brake tweaking that record could easily fall as well. Or perhaps I'll have to do it myself, I can usually pick up a couple of tenths on Bill in the same machinery...
entry 1418

June 7, 2008:
My friends Axel and Steffi came to visit, and they brought their friend Andre along.
Axel's known me since the beginning of my little Seven obsession, and this was his first chance to try the car. So I dusted the poor thing off, filled it with fuel and it burst back into life after a bit of a hibernation.

Axel reported that he actually fits quite well, something that's never been true of any similar car. He put a fair number of miles on it as we travelled around the area visiting various spots, such as the garage housing the berzerk turbo Westfield. That got him grinning.

Andre is a Caterham fan who's had the chance to drive a CSR 260. So it was quite interesting to hear his feedback on the car once we made it to the track. The track? Of course.
entry 1419
We managed to talk our way on to the track for a little play time.
All of the toys came out, as both Andre and Axel were eager to try the Targa Miata out as well. And of course I went out for a few laps. Well, I had to.

Both of the visitors absolutely loved the car. Axel spent all of his time countersteering and laughing, while Andre was turning some pretty good times. Both really enjoyed themselves.

For me, it was the first time to have the car on the track since last August - and the first time to drive it on the track in the "forward" clockwise direction in a long time. I've been spending every possible track minute in the Targa Miata, preparing it for the upcoming race. Driving the Seven was a bit of an eye-opener to be honest. I'd forgotten how physical it was. The brake pedal is rock-hard and needs a good firm push, the throttle pedal is a bit heavy (due to an extra throttle return spring that's an experiment) and the steering requires a surprising shove. Of course, everything in the Miata is power-assisted and it's a more delicate car to pilot - as it has to be, since I'll be driving it for a week of 12-hour days. But would the Seven be more effective if it was a bit lighter to drive, or would it simply be more effete? I'm not sure, I'll have to think about that. I might back the brakes off one more master cylinder size just to try.

The Seven is also set up to oversteer. Now, this is quite a bit of fun and you never have to worry about the front sliding out on you. But my driving style must have changed somewhat over the past months because I initially thought the car had a problem with the rear tires! A fast lap is mostly spent managing the rear. Very entertaining, but perhaps a little less hairiness might make the car easier to drive and quicker, without giving up the ability to rotate it on a dime. I have some ideas, this will be fun to try. Don't get me wrong, the car doesn't handle badly and it's still a complete riot. I was turning mid-1:04s which is pretty respectable - my best time in this configuration is a 1:03.3. But I wonder if it can be improved with a few fairly minor tweaks to the alignment and master cylinder sizing.

The Targa car benefited greatly from my experience with the Seven, and now I think it's time for the pollination to go the other way for while.
entry 1420

July 7, 2008:
Autocross time!
I decided I'd been spending far too much time on the Targa Miata, and that it was time to take the little monster out again. And it felt good. The car is just so quick, even at 9,000' above sea level. It dances around so well that I'm able to exploit it fully quite easily.

I took the fastest time of the day in a fairly competitive race, but the Seven really is in a different league than most other cars. I could tell when I'd put in a good run by how much I was giggling when I got to the end.
entry 1421

July 15, 2008:
Car for sale!
Well, briefly. Chris Fiaccone's bike-engined car was one of the four cars seen in the Car and Driver article. It was beautifully built and looked like a hot rod version of a Locost. The fact that it has a 900cc bike engine and weighs under 1000 lbs doesn't hurt. When Chris decided to put the car up for sale, I told him I'd mention it here.

But it's not for sale anymore. I also mentioned it to my coworker Brandon. Okay, maybe "mentioned" is the wrong term, I called him up and told him to buy it. He's wanted a Locost for a while and this one is a fine example at a very reasonable price. He agreed, and now there's a third seven-style car hanging around Flyin' Miata. It would seem they're contagious. And it's going to be tough to keep in front of Brandon at the autocrosses, we usually have pretty good battles when we're in similar cars.
entry 1422

August 1, 2008:
Hello, police? It seems someone has stolen my differential...
While this is true, it was me who stole the diff from the Seven.
I was hoping to avoid this, but I need the Guru for the Targa Miata race car. The Seven will get a Torsen in exchange. It'll be interesting to see how it affects the behavior of the little car - has the Guru been masking any bad habits, or will it make no difference at all? I'll have the diff back in a week after the ring and pinions are swapped around.
entry 1423
Since it's out, here's a shot of my PPF substitute.
I don't think I ever took a good picture of it before. This bolts on to the front of the diff, and then three bolts are run through the side of the transmission tunnel. Everything was still nice and tight when I removed it and it's undergone a fair bit of abuse in the last few years - so I think it's fair to call this little bracket a success.

Less successful was the fact that I managed to pull the driveshaft out of the transmission while removing the diff. I'm not sure I have access to that without pulling the interior transmission panels - I hope I don't have to do that!
entry 1424
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