Wednesday, October 12, 2022

Quieting down the Revoslot Cars

 Now that I have the Tire Truer [and I'll likely be talking about the benefits of it for awhile], I'm starting to think of a few things that I'm looking to do. I know what I said about keeping these cars as close to box stock as I can while making few modifications, but with the tire "issue" out of the way, now I can see what might need to be done, or at least tried. 

And while I still have the Slot.it cars to put on the Tire Truer, my main concern right now is to quiet down the seven Revoslot cars that I have. They all make basically the same sound: a loud grind. 

This beauty is a lot of fun to drive, but man is it loud.

Harry at HomeRacingWorld has been doing a great series on his YouTube channel tuning his Revoslot cars, which I have been watching because we got the same cars at almost the same time. He talked about the issue causing so much noise, and it's that the cars come stock with a 12-tooth pinion. He suggested replacing that with a 9 tooth, did the thing, then showed off the cars running. It was certainly impressive and sounded much better. Then I was on Dave Kennedy's Sunday Chat and asked him about it, and he confirmed it. 

Since I didn't have access to the particular pinions Harry was talking about, I bought what my local dealer has in those measurements. I only got a couple to start, and if they work, I'll order more. I suspect they will. I also bought a Pinion Puller by Slot.it to make the job easier. And since I have 7 cars to change, tools like that save a lot of headache. 

UPDATE:

I got a chance to do it, so I started with the Escorts. Both of them came with 12-tooth pinions, and I planned to swap them out for 9-tooth pinions. That should cause less gear mesh issues. 
Using the pinion puller was pretty intuitive. I was able to swap out each pinion in a couple of minutes. The puller stayed nice and straight and didi an admirable job. 

After changing the pinions, I tested the cars. They were not only quieter, but they ran a lot smoother. No more of that grind, more like the sound of an aluminum chassis slot car. The sound is more like a small note than a loud noise. There is still a vibration issue in some of the cars, but I have some stuff to fix that. 

Since I had the pinion puller out, I thought I would mess around with one of the Alfa GTAs and see if I could get them quieter. They came with 9-tooth pinions, but I noticed on both Alfas that the pinion was sitting pretty far off the motor and was making contact with the spur gear on the back half. I pressed the pinion in so it was just off what looked like the obvious place it should be. This gave me more flexibility with the motor position, which have me more control over gear mesh. So that's a win!

My opinion is that the Revoslot Ford Escorts should come with 9-tooth pinions and not 12-tooth. Dave Kennedy was right in saying this was a mistake that needs to be fixed.

Monday, October 3, 2022

Overdrive Sprint Race - Saturday Special Invitational

 Alright, sports fans! A three-day weekend means it's time to go racing! This race is reserved for the cars that have gone through the Overdrive Tire Truer. At the time of this writing, that's 22 cars, but it's possible more cars will be added as time goes by. First round will be 25 laps, 2nd round of Top 10 cars will be 50 laps.

The track layout has been expanded from the previous test track to include a 360° loop overpass. All cars race on the inside lane. 

I was doing some practice laps and found it to be a little tricky to remember when the loop happens. I mean, it's there, and it's not going anywhere. But when you're driving it, something about going under it cleanly on the front stretch and having a somewhat blind turn into the loop adds to the challenge of keeping the speed up. Using this many 1/60's will make this a tighter, technical track anyway.

The Revoslot cars haven't been through the Truer yet, but they likely will towards the end of this first wave of 22 cars. They should be eligible to race when their time comes. Of the 22 cars, every one of them went through the Truer without issue, and I tested them after to make sure everything was okay. One car that gave me concern is the Tergal 908. It looked like the rubber was starting to flake off the outside edges of the tires. I'll run them as-is and keep an eye on them. If they act up I'll switch to urethanes. 


Overdrive Sprint Race Semi Final Notes:
First Round - 25 timed laps
Trued tires only
10 cars advance to Finals


Results:

Car                              Time          Lap      Offs           

1. Elva #47                       1:41.03       4.04        0
2. Lola T70 #21                1:42.69       4.11        0                  
3. Elva #2                         1:42.83        4.11       0                    
4. Lola T70III #7              1:44.22       4.16        0                   
5. Lola T70 Red                1:44.33       4.16       0
6. Jaegermeister 917/10    1:46.45       4.24        0                    
7. Lola T70 Blue               1:48.00       4.32        0
8. Bosch 917/10                1:48.29       4.33        0
9. Elf 908                          1:48.63       4.33        1  
10 Rothmans 908              1:48.79       4.36        0
11. Gulf 917 #10               1:48.84       4.36        0                 
12. Uniroyal 917/10          1:50.47       4.4          0                   
13. Sunoco M6A               1:51.39       4.44        0
14. Gulf 917 #9                 1:51.89       4.46        0
15. Lola T70 MKIII #8     1:52.28       4.48        0
16. Tergal 908                   1:57.28       4.68        0
17. Gulf 908                      1:57.75       4.68        1
18. Rothmans 917             1:58.25       4.72        0
19. Lucky 917                   1:59.23       4.76        0 
20. L&M #7                      2:00.14       4.8          1
21. Sunoco 908                 2:02.06       4.88        0                                                                      
22. L&M #6                      2:02.28       4.89        0


Okay, let's talk about some cars. Since the track was pretty tight with an extended overpass, I approached the master power like I would for a technical layout: set to about 2.5 and left there. This allowed plenty of throttle and more control over the car itself. I didn't need more power than that, so I went with the shorter setup. I think the cars benefitted from it.


Most of the field had completed their runs when this car got going. It didn't once slide out, no matter how hard I pushed it. Kept setting high laps, even late into the race. Absolutely crushed it.



While another late entry, I thought the red Lola ran a fantastic race. It has that same smoothness that the #21 Lola has. The trued tires have made this car whisper quiet and masterfully efficient. A respectable 5th place today.



Had the Elf car not wrecked today it would have been in the top 5. It ruled the 908s today, even while crashing. And it was all my fault. All of the crashes were on the last 180° turn. Otherwise it was running very well. Crash out and still finish in the top 10. Impressive. 



The best a Gulf Team car could do was 11th place. In order for them to be a dominant team, they're going to have to have better showings than that. While the #10 ran a smooth race, and the 917 wasn't the ideal car for this layout, it still isn't enough.


While I'm not surprised this car is giving me issues, it's still giving me issues. At first I thought I fixed it, being a tire rub. Now I'm not so sure. Intermittent power loss throughout the race. Suddenly it would run at about 80%, then it would be back again.



One of these cars runs really well. 

The other two are L&M cars.



And that oughta do it for this race. I'd say the tire truer certainly improved every car it got involved with, and also helped point out what needs to be done to the cars now that the tires have been taken care of. Lots of setup and adjustment on these cars now. 
If you're wondering whether to get a tire truer, think of it like this: if you're the kind of person that has multiple cars, have experimented with sanding tires freehand, have issues getting your cars to settle down, or just want to be a stickler for things, then YES. A tire truer is a necessity. Know that you'll need a power supply to run it, something like this:



Although it costs as much as two cars, the benefit it gives ALL the cars is totally worth it. Each car is a pleasure to drive now and they handle fantastically. I'm going to do the rest this week and get everyone ready for the Championship season.