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Patrick · 10:34 PM

Wow, you change your mind a lot.

Personally I wouldn't get the A123's for a race car. Big, bulky, ugly, and not as powerful. They drop their voltage a lot under load, so it sounds like you need 2p to get decent performance and runtime, unless you go really high voltage. I guess they're cheaper and safer, so they'd be good for a basher, but I'd prefer lipo for racing. If you only went with 3s A123 you'd need a lot of amps to get decent power and hit 34mph, which would mean poor runtime, more heat and poor performance, because the A123's wouldn't be able to hold their voltage under so much load. I wouldn't use less than 5s with A123, and I think you'd still need 2p too get decent runtime and performance.

I still like the 1515 2.5d on 5s lipo (it's good on 6s as well), but the 1515 1y on 4s should be ok as well I guess. I think the 1.5d's kv is a bit too high for such a big motor.
I went with 5s instead of 4s, so I could keep the amp draw and temps a bit lower when geared for a certain speed. I wasn't sure if using the 10C true rc packs on only 4s would be pushing them a bit, but they hardly get warm on 5s, so I guess they'd still be ok on 4s geared for the same speed. The 3s2p true rc packs are only $25 more than the 2s2p packs, so going 5s wouldn't be that much more, since you already have the controller and the motor will still be the same price.

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Patrick RC-Monster Aluminum Offline Posts: 862 Join Date: Dec 2006 Location: Perth, Western Australia	11.22.2007, 09:28 PM Wow, you change your mind a lot. Personally I wouldn't get the A123's for a race car. Big, bulky, ugly, and not as powerful. They drop their voltage a lot under load, so it sounds like you need 2p to get decent performance and runtime, unless you go really high voltage. I guess they're cheaper and safer, so they'd be good for a basher, but I'd prefer lipo for racing. If you only went with 3s A123 you'd need a lot of amps to get decent power and hit 34mph, which would mean poor runtime, more heat and poor performance, because the A123's wouldn't be able to hold their voltage under so much load. I wouldn't use less than 5s with A123, and I think you'd still need 2p too get decent runtime and performance. I still like the 1515 2.5d on 5s lipo (it's good on 6s as well), but the 1515 1y on 4s should be ok as well I guess. I think the 1.5d's kv is a bit too high for such a big motor. I went with 5s instead of 4s, so I could keep the amp draw and temps a bit lower when geared for a certain speed. I wasn't sure if using the 10C true rc packs on only 4s would be pushing them a bit, but they hardly get warm on 5s, so I guess they'd still be ok on 4s geared for the same speed. The 3s2p true rc packs are only $25 more than the 2s2p packs, so going 5s wouldn't be that much more, since you already have the controller and the motor will still be the same price. Last edited by Patrick; 11.22.2007 at 10:34 PM.