1518 4s?

[simplechamp]

I just installed a 1518 in my F8T and have it geared 16/52 on 4S for about 40mph (I should note the F8T has 43/13 ratio in the front and rear, not very common in truggies).

The max RPM achieved with the 1518 on 4S is a bit low of the 30-35k sweet spot, but I think it is still OK. The extra torque provided by the 1518 over the 1515 should allow you to go up a few teeth on the pinion and gear for the same speed as with the 1515.

[kneedeeppow]

not sure if i am using briang's calculator right for my rc8t on 4s. i come up with 12t pinion on a 46t spur gearing to 40mph(which is probably more than really want). i was thinking more on the lines of 18t+ pinion but end up with speeds of 60+mph.have all the feilds filled in to the best of my knowledge. can anyone point me in the right direction?

[Nard Cox]

Originally Posted by kneedeeppow

not sure if i am using briang's calculator right for my rc8t on 4s. i come up with 12t pinion on a 46t spur gearing to 40mph(which is probably more than really want). i was thinking more on the lines of 18t+ pinion but end up with speeds of 60+mph.have all the feilds filled in to the best of my knowledge. can anyone point me in the right direction?

Did you have the option ''put RC in trunk of 1:1'' switched on? I think you did something wrong, try again and post a screenshot of your data input and output.

[thzero]

Something sounds wrong. Using the http://scriptasylum.com/rc_speed/_top_speed.html calc, here is the RC8T with 46t on 4S with LPR tires. Thats ~26mph, without factoring in any ballooning. Looks like you'd need to go to 14t for ~30, 16t for ~35, and 18t for ~40mph.

Differential Ratio: 4.3
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 46
Pinion Tooth Count: 12
Total Voltage: 14.8
Motor KV: 1800
Tire Diameter (inches): 5.6
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor Coil Resistance: 0
Spur/Pinion Ratio: 3.83 : 1
Total Ratio: 16.48333 : 1
Tire Circumference (inches): 17.59 inches (446.86 mm)
Rollout: 1.07:1
Total Motor Speed: 26640 RPM
Vehicle Speed: 26.93 mph (43.25 km/h)
Effective KV Value: 1800
KT constant: 0.75 oz-in/A

Originally Posted by kneedeeppow

not sure if i am using briang's calculator right for my rc8t on 4s. i come up with 12t pinion on a 46t spur gearing to 40mph(which is probably more than really want). i was thinking more on the lines of 18t+ pinion but end up with speeds of 60+mph.have all the feilds filled in to the best of my knowledge. can anyone point me in the right direction?