Slow Car Fast
November 26, 2010 - Of course, with the car basically complete, it's time for a drive!
Not just a pootle up and down the street, but a real test drive. The car's never been further from home than my "around the block" test drive that totals about 6 miles, and it only did that once before being disassembled.
First, I drove down to the gas station that's almost exactly a mile down the road. Janel didn't feel I should be on my own, so she followed in a support vehicle. Luckily, support was not needed. The car did have a metal-on-metal scraping noise that was directly related to wheel speed, but I suspected that was a brake dust shield that had been bent and was making contact with the rotor. Inspection upon return to the garage showed this to be the case, so I bent both front dust shields back into their original shape and fixed a wire on the fuel gauge.
Now it was time to go a bit further afield.
entry 474 - tags: testing
November 26, 2010 - I took the car around my test loop.
Coming up to the house, I decided I hadn't had enough so I kept going to a good spot to take pictures.
How was it working? Well, it needs an alignment pretty badly. I'd guess it has a bit of toe-out and almost no caster, meaning the steering is darty and doesn't self-center very well. I need to sort out both spring rates and damping - never having set up a car with a live rear before, that's going to be interesting. The car also squeaks and rattles quite a bit. Nothing too surprising here.
How does the powerplant feel? Monstrous. After taking things easy to make sure the temperatures were good and there were no obvious problems, I started giving the car a bit of throttle. And it likes it a lot. This is a seriously fast little car. The shift pattern is very tight, the pedal effort is nicely matched between the throttle, clutch and brakes and other than the non-centering steering it feels good to drive. Engine temperatures stayed fairly low and I didn't get the chance to confirm if the fans were kicking in. The intake air temperature was only a couple of degrees above ambient.
Noise levels are reasonably high, with a big resonance at 1500 rpm. I still don't have my sound deadening in the rear yet and when I got home, I realized that the exhaust fires right into the rear valence. That's easy enough to fix and is probably causing a lot of the noise. I'll fix that tonight or tomorrow.
entry 475 - tags: testing
November 26, 2010 - I did come home from the drive with a to-do list.

  • fix a bad squeak in the rear hatch
  • flatten the flanges on the headers (especially the passenger's side) and install gaskets
  • find the heater fan wiring and hook it up
  • find the cause of a groan on medium braking

  • align the car
  • try softer springs all around to see how they work out

The car's booked for an alignment on Wednesday morning. The hatch squeak should be fixed if I've found the problem. Softer springs aren't required but I want to try them out. I'll do a nut-and-bolt on the front suspension to find that groan, and put some more brake anti-squeal on the pad backs.
entry 476 - tags: testing
November 26, 2010 - I don't know why I find this angle so much fun, but I do so you're stuck with it.
After taking the pictures, I bedded the brake pads and headed home. I'm not sure I got the pads hot enough, but I'd prefer to have the alignment done properly before I go too nuts. It'll be interesting to see if the car will align, that will be a moment of truth for my suspension building skills!
entry 477 - tags: testing, brakes
November 30, 2010 - A big adventure for the MG!
I drove the car to work today. Intake air temperatures of 25F tells me two things: the air filter location is picking up nice cold air and, and baby it's cold outside. The heater works but there are a few holes in the firewall for wiring and the like that let in a cool breeze.
The suspension is working quite nicely from a ride standpoint. The car is now absorbing bumps well and shows good composure. No word on how it handles yet, I'm withholding judgment there until all the wheels are pointing in the correct direction. But the car feels right. It has 300 lb front and 225 lb rear springs at the moment.
I took the interstate on the way in to see how the car deals with highway speeds. Answer: pretty darn well. No evil habits showed themselves at high velocities, up to 75 mph based on other traffic. There are a few rumbles through the body that I suspect might be the exhaust leaning up against the frame - there's one point where the piping is really, really close. A cleverly placed dent will solve that problem. I'll check the bottom of the car to see if there are any rub marks. I'm hoping that's what I was feeling, it didn't quite feel like mechanical vibration. The near-solid motor mounts were certainly adding a bit of buzz.
This was the first chance a number of my coworkers had to check out the car. Bill, my boss at Flyin' Miata, was impressed with the exhaust packaging and can't wait to drive the car. I asked him to wait until I had the alignment done. Lots of commenting on the packaging to make the engine fit. Adam stood to one side, looked at the wheel well and said "I can see the headers!"
So far, so good. Now, how will the drive home in the dark work out?
entry 489 - tags: testing
December 23, 2010 - The car is now completely assembled and all the debris has been vacuumed out of the interior.
It's certainly not done, but it does look respectable. Before I started, the crack on the top of the dash was barely noticeable with all the other problems. But now the interior looks good, the piece of black tape I just slapped over top is very obvious. Oh well, it's only a temporary fix. One nice touch is that I managed to fit the reset/programming button in where the old choke cable went.
So of course, I took it for a drive. The speedo is reading fast, so I don't have it calibrated correctly yet. A call to Jeremy at Flyin' Miata reveals that the T56 has a 17-tooth trigger wheel on the output shaft, so I'm seeing 17 pulses per driveshaft revolution. Okay, now I can calculate the correct pulses per mile. I had 40,000 in there as a rough guess, looks like it should be 52,209 with my current tire diameter.
The car's quieter. Not exactly a Lexus, but more manageable. As I lay more carpet down in the footwells, it will improve. I think I've also missed some spots under the rear deck, and I may try some rubber motor mounts eventually. But it's pretty good. The new wheel position is a step up, I'm happy with that.
The car is certainly not sorted out from a suspension standpoint yet, though. I'm not sure how much of what I'm feeling is a very high amount of unsprung weight in the rear with that live axle - a 2200 lb car with the rear end from a small truck is certainly hurting in that regard. I think I need a bit more rebound damping on the front shocks, and I should probably start looking at fitting some sway bars. I also have some Falken Azenis 215 tires on the car which have very, very stiff sidewalls on them. There's a set of 615s in the garage ready to go on, but it is really tempting to swap in some wider 15" wheels and a more compliant tire. That means spending a big chunk of change, though, so I'll probably put that off for a while.
While filling up the gas tank, I got in a conversation with a few other guys and ended up popping the hood. I suspect this will become a fairly common occurrence...
entry 521 - tags: testing
December 26, 2010 - A (poor) shot of the complete dashboard.
Quite a change from the original look. The overspray on the carpet isn't really noticeable in person, you only see it when it's all lit up with the flash.
There hasn't been any major work on the car in the last few days, I've just been driving it. The defroster got a test on Christmas night when we had to head home after dinner, and it passed. I still need to work on sound levels coming from the back of the car, but a bit more of my silver cladding should help out there. I suspect that this would not be a problem in one of the convertibles, but the coupe body does provide a nice resonance chamber at around 1500 rpm. Still, I've been enjoying it quite a bit so far. The speedo works well and seems to be accurate, the dash lighting is about as good as could be expected and overall the car is working fairly well. The new Bosch H4 headlights I installed put out ridiculous amounts of light, just as I'd hoped.
Just because it's that time of year, I took a look back to see what I was doing around this time in the past. A year ago, I drove the Camaro into the garage for the final time. Two years ago, we decided to disassemble the interior. And this year we used the car to drive to Christmas dinner. I'd call that progress!
entry 523 - tags: interior, testing, looking back
July 24, 2011 - Track day test!
I was at the track testing the Targa Miata, and Janel stopped by with the MG. It garnered quite a bit of attention - all you have to do is park this car with the hood up and it will cause some double-takes.
And of course, I took it out on the track to see how it would do. Not to see how fast it would go, but the track is the ideal place to test the handling of a car safely. And as you can see in the video below, I did have a bit of fun. The first wobble coming on to the front straight was because I provoked the car to see what it would do. I was a bit slow on unwinding the counter-steer. Oops. But the suspension coped with the bump coming back on to track just fine, working as designed. Once I was recalibrated, I was able to hang the back end out fairly consistently when I wanted to. The biggest problem was that the body did move around a bit as the car was hooking back up, so you can't pitch it around like you can a Lotus Seven. Well, you can't really do that with anything.
The brakes were the weakest point. It feels as if the pads aren't properly bedded. They did feel stronger on the street after the track session, which would back that up. I'll take the car out and bed them again.
And of course, the excitement at the end. Fire! A couple of laps in, I heard a bit of a bang from the back followed by the smell of burning rubber. Yes, well, after the way I'd been driving burning rubber was to be expected. But this wasn't molten tire from spinning, this smelled like someone had actually lit rubber on fire. My first thought was that a tire was rubbing badly on something, so I started to back off a bit and come in. When I came towards the pit entrance, I was greeted by a very excited Brandon waving me down. Apparently I'd blown a big fireball and run around with the back of the car trailing flames for a bit.
It was pretty easy to figure out what had been going on. The vented fuel cap had been leaking a bit of fuel under hard left turns, and it eventually lit off. The burning rubber was the rubber gasket around the filler neck getting wobbly. No permanent harm done, but it did mean the track time was over for the day. I'll find a way to stop that from happening again. Not a major problem, but it sure was dramatic!

entry 632 - tags: track, fire, testing
July 24, 2011 - It wasn't all fireballs and oversteer yesterday.
Janel spent most of the day running around town in the little car, and seems to have quite enjoyed it. The car still has a tendency to pop out of reverse (and will continue to do so until I pull the transmission to fix it) so she planned her stops as pull-through only.
Until we were driving home from the track. I was leading the way in the Targa Miata, enjoying the view of the little tiny black car in the rear view mirror when she suddenly pulled over the side of the road about a half mile from the house. The mysterious fuel problem had returned.
Checking the fuel pressure revealed the problem - 20 psi. It's supposed to be about three times that. Between the inoperative fuel pressure gauge and the spill earlier today, I (once again) decided the best thing to do was to fill up the tank. And this time, it worked. Instant 60 psi pressure and the car came to life after a couple of tries. We took it home, then ran around town some more with the car at night without any problems.
I'd really like to know more about what's inside that fuel tank. No baffling, that much is clear. But where is the pickup? Janel described the car as losing power after a right turn, which would have sloshed fuel away from the side of the tank that has the pickup. And it just didn't come back all the way. If the extra fuel in the tank hadn't fixed the problem, I was going to see if I could bleed off any air bubbles in the system. But that may have to wait until the car fails again.
As a possibly related problem, the car sometimes doesn't start quite right. It'll pop once and then just crank. Cycling the key brings it back to life. I really want to know what's in that tank, as everything else in the system is something I'd consider to be a known quantity.
The car really does look cool out on the streets, especially from a distance. It gets a huge amount of attention. And Janel quite enjoys the effect of the accelerator. A hot-rodded vintage pickup passed us in traffic, and I thought Janel was going to rear-end it when things cleared. She was quite disappointed that his big fat tires were mostly for cruising up and down the strip.
The picture has nothing to do with driving around town, it just shows the car on track and not on fire.
entry 633 - tags: fuel, testing