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Old 11-25-2013, 05:14 PM   #1
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Default Tc4 need more speed?

I'm running a tc4 with a tekin RS pro, redline (2nd gen) 5.5t brushless motor, venom 2s lipo 70c 5300, 72/26 spur/pinion. The esc is set to an agressive profile as well. I just hooked up my garmin GPS and ran not a few times in my street. I was disappointed to see it only hit 47mph. Unless the gps is bad, is it me, or should this setup go much faster than 47mph??? Any input would be greatly appreciated.
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Old 11-25-2013, 07:25 PM   #2
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The gearing is pretty high for boost,if you're running any boost... You'll need a laptop for boost though... 47mph is pretty slow for your setup.... You should go over 50mph with that setup, unless the 5.5t motor is way less than 7800kv...
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Old 11-25-2013, 07:53 PM   #3
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Originally Posted by bertrandsv87 View Post
The gearing is pretty high for boost,if you're running any boost... You'll need a laptop for boost though... 47mph is pretty slow for your setup.... You should go over 50mph with that setup, unless the 5.5t motor is way less than 7800kv...
The motor is rated at 7550 kv. Not running any boost that I know of. My lhs said I should be running like 60+ with that setup. The car seems like it's an animal too. That's why I question the 47mph readout. Should I lower the pinion to say like a 23t? I just felt like if I ran too much acceleration I wouldn't be able to control the car off the line.

Last edited by kmc978; 11-25-2013 at 07:57 PM. Reason: Correction: motor is rated at 7750kv
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Old 11-25-2013, 08:07 PM   #4
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I don't think 60+mph is attainable with a 5.5t blinky without very tall gearing(6.1fdr)... If you're not getting any motor heat now at 6.92fdr, you can gear it up slowly and temp it, but most of the racers I race against only used the Rspro with boost on 6.5t motors or higher, never lower.... Their cars with 6.5t boosted were much faster than 50mph, maybe 58mph to 62mph.... I am sure if you use boost you will top that....
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Old 11-25-2013, 08:10 PM   #5
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Ok cool. How do I use boost? I didn't even know electric motors had "boost".
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Old 11-25-2013, 08:11 PM   #6
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And the motor is very cool every time I run it so at this point heat isn't an issue.
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Old 11-25-2013, 08:12 PM   #7
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Also, if you don't run a spool/lcd combo up front, you will lose acceleration and top speed. You should not have a regular differential up front. It won't handle the power and slip forever...

Last edited by bertrandsv87; 11-25-2013 at 08:23 PM.
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Old 11-25-2013, 08:15 PM   #8
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To get boost, you'll need to go to a lhs that can program your speedo for you, or you can do it with your laptop, and tekin hotwire($30) programming card by downloading the software Off the tekin website...
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Old 11-25-2013, 08:25 PM   #9
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Yes I actually just started looking into the the hotwire device. Might pick one up. As for the spool/LCD, is that like a limited slip diff? Such as the assembly in the rear? I'm running the steel out drives in the rear already.
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Old 11-25-2013, 08:34 PM   #10
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The spool is a solid axle : Associated part #1703 $17...
The lcd drives are losi double cardant joints: part# losa3344 $38 to $40... They reduce driveline vibrations when turning. You will get alot more speed with those, but if you want to make your own slipper spool with the tc5 slipper pad, you will have to go to the tc4 thread, and ask the guys there how to build one... It's cheaper than the spool/lcd combo, and more forgiving when you hit the wall too... I believe the losi Parts are getting pretty rare these days, so the slipper spool might be the only solution...
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Old 11-25-2013, 08:35 PM   #11
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You can turn up the motor timing to get more top end. I think the tekin motors are set very low on timing out of the box.
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Old 11-25-2013, 08:43 PM   #12
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Ok I just checked out the solid axle and I'm positive I already have that installed. I actually went to go put one in and when I opened up the front diff, it was already in there. As for the motor timing, I think it's stock setting is 10 degrees. What's a good spot to bump it up to?
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Old 11-25-2013, 08:46 PM   #13
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Searched the losi part # on towerhobbies site and nothing came up. What's a double cardant joint?
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Old 11-25-2013, 08:47 PM   #14
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I would go up 10deg per run until the motor starts to get warm ( not hot ) . With a 5.5 you should be able to run 6 minutes and be around 100 degrees.
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Old 11-25-2013, 08:49 PM   #15
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Just remember if you start adding boost from the Speedo to take back out the timing in the motor.
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