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Old 11-24-2012, 11:20 AM
  #1516  
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Thank you azeroth for replying. so it's the wheel adapters that are offset, not the chassis. That makes sense. I'm leaning towards the dirt oval version as I like the pivot ball rear and the shorter rear shocks! However,what about the solid center spool on the dirt oval? How will it affect the car on a roadcourse?

Also, am I correct in assuming that the SNR graphite chassis plate will fit the dirt oval car the same as the regular GTPE?

Still trying to figure out which Turnigy or Nano-tech lipo to use with this car and the electronics package I described in my earlier post.
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Old 11-24-2012, 11:56 AM
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Yes my chassis will fit the dirt oval. I would go with the dirt oval just because
of the rear pivot ball you get more for the buck.
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Old 11-24-2012, 01:17 PM
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Originally Posted by SNR Graphite
Yes my chassis will fit the dirt oval. I would go with the dirt oval just because
of the rear pivot ball you get more for the buck.
That's what I was thinking! The dirt oval with the pivot ball rear and the shorter rear shocks seems like the hot ticket. Any issue with the solid center spool? I don't know much about how they work and what effect they have on handling.

SNR, I noticed quite a few posts back that you were going to get a 3S lipo for your car. I was thinking the same thing, but most here seem to prefer the 4S.

From my original post that showed the indoor concrete kart track that we will be racing on, I'm thinking that the 11 volt 3S might be better than the 14Volt 4S. After all, I'm not interested in "speed runs" of 70+mph; I'm planning on racing this car on that roadcourse layout. The motor I plan on is the Turnigy TrackStar sensored 2350KV.

Any suggestions?
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Old 11-24-2012, 05:08 PM
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If you going with 3s then you're going to need a higher KV I would go with a 2650. I've always ran a spool in the middle I've try a diff. but it over heat my motor and it does not accelerate like a spool. A diff is good if you don't have traction but it sucks when their is a lot of bite.
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Old 11-24-2012, 05:18 PM
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The Turnigy motor that is 2650KV is sensorless, which I'm not sure I want, as I've heard that sensorless systems are prone to "cogging", which isn't good for racing! That's why I was looking at the 2350KV motor, because it is a sensored motor.

I guess I could go with 4S if needed. The esc is rated at 120 amps.

Not sure yet what the grip will be like at the kart track, as no one has raced on it as of yet. But, it DOES look to be very clean and smooth, so hopefully the traction will be decent. So the solid spool will hopefully work well there.
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Old 11-25-2012, 04:26 AM
  #1521  
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Originally Posted by SNR Graphite
If you going with 3s then you're going to need a higher KV I would go with a 2650. I've always ran a spool in the middle I've try a diff. but it over heat my motor and it does not accelerate like a spool. A diff is good if you don't have traction but it sucks when their is a lot of bite.
I agree with a 2650 on 3S is a nice combination. For the inside sections on most tracks a 2650 on 3s is plenty of power. It will keep you a lot more consistent through the turns but the problem comes in on tracks with long straights the 3s won't give you enough top end. Like our track that has a straight thats 240' a 3s just doesn't provide enough power for the straight.
What might be a good idea is 2650 on 3s with a 2-speed. I really think it could be a killer combination if you can set it up right.
I had a new GT2 roller with a 2-speed and RC monster brushless conversion I wanted to try it with a 2650 mamba combo I had sitting around but I ended up selling the roller and now I kind of regret it
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Old 11-25-2012, 07:54 AM
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Originally Posted by Voltron989
I agree with a 2650 on 3S is a nice combination. For the inside sections on most tracks a 2650 on 3s is plenty of power. It will keep you a lot more consistent through the turns but the problem comes in on tracks with long straights the 3s won't give you enough top end. Like our track that has a straight thats 240' a 3s just doesn't provide enough power for the straight.
What might be a good idea is 2650 on 3s with a 2-speed. I really think it could be a killer combination if you can set it up right.
I had a new GT2 roller with a 2-speed and RC monster brushless conversion I wanted to try it with a 2650 mamba combo I had sitting around but I ended up selling the roller and now I kind of regret it
Thank you for your help. The kart track however does not have any real long straights as you can see in the pic; it has more turns than straight sections, and the straights are somewhat short.

I'm still concerned with sensored vs sensorless motors. Will the TrackStar 2650KV sensorless motor bog down under acceleration, or "cog" as they say; or will it accelerate properly? No one seems to have provided an answer to that question yet.
Attached Thumbnails Ofna Ultra GTP2e-indoorkarts1.jpg  
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Old 11-25-2012, 07:55 AM
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I am thinking about trying that new Ofna GT V2e car it really has a good internal ratio and all the cva look lightweight.
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Old 11-25-2012, 08:17 AM
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i am running center spool you dont have the car dif out when you loose traction on one corner the rear pivot ball is a must have in my opinion i also run the nitro car mostly but the e sure is nice on practice days or the quik stop at at local lot and get some wheel time in throw down some dots and have at it. the snr chassis that uses the dm1 bumper and difuser is a nice addition i have just made 3 7075 aluminum chassis plates for my nitro car using the same idea to get the ride height down where it belongs. hey 4mm is a mile when it come to cg but i am running a tekin 2650 and t4 on 4s and the car is controlable but brutal fast
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Old 11-25-2012, 09:29 AM
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Originally Posted by SNR Graphite
I am thinking about trying that new Ofna GT V2e car it really has a good internal ratio and all the cva look lightweight.

WHOA!!! when is that due out? Just googled it, haven't heard of it till now.
Looks amazing. If that saddle setup can take standard 2s lipos im in love!

** Dafuq? $500 at nitrohouse? that doesnt seem right.
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Old 11-25-2012, 10:19 AM
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The GT-V2e does look awesome! It has a 4.3:1 diff ratio. I really like the layout you could fit an XL2 esc with dual 4s for speed runs! I just wish it had the same 3.14 ratio as the GTP2e.
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Old 11-25-2012, 01:51 PM
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If the GT-V2e was priced lower I'd consider trying it out but for nearly the price of the Cobra GT I can't see a reason taking it over the Serpent unless you really want a long wheelbase car Just my opinion though. It does look pretty nice
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Old 11-25-2012, 01:54 PM
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I was all over it till i saw the price.
That is crazy when you think about how they have priced the GTP2e and DM1-specE in the past.
Can it be THAT ($300 more) ground-breakingly different?
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Old 11-25-2012, 02:00 PM
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Originally Posted by Team Lotus
Thank you for your help. The kart track however does not have any real long straights as you can see in the pic; it has more turns than straight sections, and the straights are somewhat short.

I'm still concerned with sensored vs sensorless motors. Will the TrackStar 2650KV sensorless motor bog down under acceleration, or "cog" as they say; or will it accelerate properly? No one seems to have provided an answer to that question yet.
Will only cog a little when rolling it from a dead stop. Once it's rolling its hard to tell a difference from sensored to sensorless

Don't know how the visual of the car will be on that go-cart track lol
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Old 11-25-2012, 02:02 PM
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Yeah, cogging is usually only noticeable at very low speeds and from dead stop.

If you are seeing it coming out of a corner to a straight at regular track speeds there are likely other issues to sort out.
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