Thread: USVTA or ROAR VTA

f103rm with rubber tires, we are running at xtreme silver ca is mine or 21.5 brushless or foam tires

I received an Edge/25.5T VTA combo yesterday. I have the new Club combos coming in March.

I just about have everything together for my VTA setup, and hope to have it completed by the next race weekend. I will say up front that I am more than likely not going to be out there until around 1:00 on any Sunday I race though.


Kurtis

Kurtis, all you gotta do is call us and let us know you are coming or post it on here the day before.

Thanks
Bill

OK, Thanks Bill. I hope to see you guys next weekend.


Also, I am just trying to figure out my gearing and know one of the guys (no names given) is running roughly a 3.06 final drive on their VTA setup, but was wanting to see roughly what others might be running to try and figure out a good ratio to run. I have enough gears that I can run between like a 2.97 up to say a 3.22. It just seems like these final drives are very taxing on the motors and speed controls, however I am not very familiar with Brushless since my last electric venture was in the brushed world so I may not be correct in my thoughts.

Thanks,
Kurtis

Originally Posted by Cegpcola

Also, I am just trying to figure out my gearing and know one of the guys (no names given) is running roughly a 3.06 final drive on their VTA setup, but was wanting to see roughly what others might be running to try and figure out a good ratio to run. I have enough gears that I can run between like a 2.97 up to say a 3.22. It just seems like these final drives are very taxing on the motors and speed controls, however I am not very familiar with Brushless since my last electric venture was in the brushed world so I may not be correct in my thoughts.

Gearing with the 25.5 brushless is really motor-dependent. I've seen anywhere from 3.2 up to a 4.6 using the Novak motors. Because of tolerances, one motor may run the fastest at 4.0 with 40 degrees of timing, while another might be faster at 3.6 with 30 degrees of timing (mine is geared 4.4 with 45 degrees of timing). I think this is why when the USVTA guys settled on the 25.5, they went with an open gear ratio rule instead of the set range that the previous motor rules for the class had. My advice is to pick up a range of pinions and couple of spurs to gear anywhere from 3.6 up to 4.6 and then play with the timing and gearing until you find something that works for you. Another thing you need to remember is that VTA is all about corning speed and consistency. Just because a car blows by you on the straightaway doesn't necessarily mean that the car has a faster motor or gearing. When Mike Sullivan came over to XtremeZone to practice, he played with the timing on his motor, and then I showed him how to start wide and swoop in and out on the turns to keep up his corner speed. His laptimes dropped a good bit after that. Practice with the car, get consistent with it, and then play with the gearing and timing. Check your laptimes for changes and don't be afraid to go in either direction with the gearing and timing.

Thanks, I have ordered a few pions and spurs, so hopefully I will have something that works. I have everything together now and ran it today with the gear ratio at 4.47 final drive, and the car felt really good. It has a nice amount of bite on the slippery asphalt in front of my house, so I think it will be good on the track. I will need to spend a good many races getting myself back to where I was behind the controller years ago though. I will have to spend a little time getting the gear ratio and timing right. With the motor geared at the 4.47 and no timing adjustment, I get more than enough run time from my 4000mah batteries, and when done with about 8 mins of running the motor is still cool enough that you can put your hand on it and hold it there with no discomfort. I know there is plenty of room left though, so I will just need to play with it some for the first few races. What all chassis tuning parts are legal in this class, or is the chassis pretty much open in the rules.


Kurtis

This only limit on the chassis is the 1550g (1450g ROAR) minimum weight. Other than that, tune away.

Thanks, That reminds me that I need to see how much the car does weigh. I am using the steel battery tray, but I am not sure if that will be enough.


Thanks,
Kurtis