I mentioned previously that the Matra came with it's front tires already making contact with the track, but out of habit I removed the two support cups like I always do, and I think I may have put the car out of balance. It's tending to de-slot at high speeds now, especially in the Mulsanne Kink and the Sweeper. I think I'm going to go ahead and reset those cups and see if the contact is satisfactory for me. I'm a firm believer in having four tires on the track, and not two. That friction argument floating around out there is poppycock. Sorry.
The argument goes something like this: since your front tires aren't providing any power to the track, they are instead slowing down the car, so setting the car up with the tires off the track will make it go faster by taking the friction-causing front tires out of the picture. An added by-product proposed is that when going into a turn, the car will eventually lean enough to allow the front tire to engage the track for support.
Last part first: how's about setting the front tire on the track so that there's no lean to begin with?
Tires in the air? Here's a simple enough test:
Take the motor out of one of your cars. Then set up the tires so they're off the track. Put the car on the track, and give it an eager push with your finger. See how far it goes. Next, set up the car's tires so they're on the track. Repeat the putting and the pushing. Notice how much farther the car now travels? Yeah, friction would be the opposite of that. The only friction is the amount of plastic sliding along the track because the wheels are up in the air.
So anyway, off topic a bit there. Even though the Matra was doing fine before I tampered with it, I think my work adversely affected it. Regardless, I ran a 50 lap shakedown to see what it could do. It had already felt like it was right in the running from the get-go. It's even quieter than the GTII, which I didn't think was going to be possible.
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| Nice to have another car with a different number. The #10 Matra Simca 670 B. |
50-lap Shakedown Test
Car Time Lap
Matra 4:07.50 4.94
You have to go all the way back to the Frozen Tundra 50 to find a similar race to compare it with. Anything earlier would have different track parameters and couldn't really count.
At the Frozen Tundra 50 the 2nd and 3rd place cars [#8 Ford and Alfa, respectively] were two tenths of a second per lap behind the time the #10 laid down today. I had a feeling it would do well, but I wasn't expecting that. Those two cars have been tweaked to the track, whereas the Matra is still a bit away from being race-ready.
But if it isn't race-ready yet, how fast is it going to be when it finally is ready? And if all Matras run like this, then why isn't it the top of its class in racing? I never hear about it in slot car circles, and it's a perfectly lovely car. I don't get it. Maybe people prefer the other cars from the era more. Or maybe the older models aren't as refined? I don't know.
Anyway, let's do some tweaks and a bit more testing.
Thirty Minutes Later...
Instead of putting those cups back in...I just can't see why you need them...I took the screws I put in out instead, allowing more flexibility. I also redid the wire brushes, which had a not-quite-good connection. All in all I got it into a good running mode and just ran a couple hundred laps with only one off. I'll continue tweaking it, and I'll save the cups in case I just can't get it right, but I think I might be headed in the right direction now.
Two Hours Later...
I added the Porsche and the Alfa to the session and ran them against the #10 to see if it was keeping up the pace, and it certainly was. I'm noticing that due to the short nose on the Matra, most of the weight is on the back end of the car [since it's a sidewinder motor]. Early in the session I noticed the front end hopping at the start of the Mulsanne Straight. I think I might actually have to add a little ballast up front to keep the nose down. If I add it I'll try to add just enough to keep it down without weighing down the car too much. This problem doesn't happen with the Porsche because it's got enough nose to keep it on the track.
But the Matra is a lot like the Alfa up front, except longer everywhere else. The combination of these things and the low body shape, it's really a very "flat" car, meaning that most of the body has a maximum height that is quite low to the ground, unlike the other cars. That gives it a lighter overall weight, which makes it that much more important to make sure weight is properly distributed. You don't want a light car being light in the nose or the tail. The Matra weighs in three grams lighter than the Porsche, so I could add a bit of weight to it. It's now, however, two grams heavier than the GT40, which is surprising.
During the session I was dealing with a lot of dust left by the bathroom installers. It got on everything, including the track. So I've been cleaning, running, sanding and taping. I put the Alfa away and brought out the Mark II, so now I have my three newest cars running. I thought I would give a little care to the tires, since they were sliding all over from the dust.
After about 500 more laps I'm very happy with the car. The nose is down, it's fast and quiet.
I love this car. That was fast.
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