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Old 03-18-2014, 06:50 AM   #1
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Default Choosing a motor.. What kv or turns?

Hi guys.. technology has come along way since i last raced on road..15-20years.. back then we just had a 540 based motor and a sliding esc.. the track that we run at is a converted netball court.. just a "medium grip asphalt" surface... fast but technical.. whats the best option for KV Ratings and what does it mean on a on road car.. higher the kv..more power? but heat may be a issue..

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Old 03-18-2014, 08:59 AM   #2
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kv is simply "RPM per volt" - so a 4500kv on 8V (random numbers here) should reach 36000 RPM (4500 x 8).

But it is not really standardized (so different manufacturers will come up with different numbers, even if their motors had identical performance), and in On-Road racing people tend to go by turns more than kv.

However, you need to tell us what type of car you're going to race on that circuit, and in what class (modified, stock, etc) before anyone can give you any reasonable tips.
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Old 03-18-2014, 12:39 PM   #3
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I'd have to agree with DirkW on what you plan on running and what c class. This will help narrow down what turn motor you should get.
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Old 03-18-2014, 01:51 PM   #4
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I used to have a slider ESC as well 20 years ago! (damn those years fly by)
Had it in a old Tamiya!
Anyway....
Higher KV = More RPM so more top speed.
Lower KV = Less RPM but more torque (off-road)

For heat problems i find that my 7.5T gets hotter then my 4.5T since i need to crank up the boost/turbo alot more with my 7.5T to get the speed i want.
For starter i would go for a 10.5T. Hope this helps and enjoy
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Old 03-18-2014, 03:46 PM   #5
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you might want to buy a faster motor then, as pushing it with timing will never be as good a just a quicker motor.

just fyi KV is rpm per volt under no load theoretically. so it can't be used to compare motor very accurately.(already mentioned) turns is better, and for racing it is usually what is used.
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Old 03-18-2014, 05:13 PM   #6
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Quote:
Originally Posted by ThePanda View Post
you might want to buy a faster motor then, as pushing it with timing will never be as good a just a quicker motor.

just fyi KV is rpm per volt under no load theoretically. so it can't be used to compare motor very accurately.(already mentioned) turns is better, and for racing it is usually what is used.

Yep, but just one problem.. We always want to go faster! So you end up changing boost and turbo on the 4.5T too
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