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21.5t touring car

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21.5t touring car

Old 08-30-2020, 05:33 PM
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Default 21.5t touring car

Raced for the first time today on asphalt and this 21.5t motor has no punch, watts or tq.
i am geared around 3.1, revtech killshot 21.5t motor, mamba max X esc 40r slicks and an smc 5800 2s battery. My issue is I was getting completely passed on the straights and coming out of the turns on power alone. My timing is around 65 on the end bell.
Is this motor just weak? Are there different rotors? I doubt itís my battery
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Old 08-30-2020, 06:06 PM
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Is it an old/used motor? And do you think it might have been overheated?
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Old 08-30-2020, 07:12 PM
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Originally Posted by illmatic94 View Post
Raced for the first time today on asphalt and this 21.5t motor has no punch, watts or tq.
i am geared around 3.1, revtech killshot 21.5t motor, mamba max X esc 40r slicks and an smc 5800 2s battery. My issue is I was getting completely passed on the straights and coming out of the turns on power alone. My timing is around 65 on the end bell.
Is this motor just weak? Are there different rotors? I doubt itís my battery
your gearing and timing Are way off
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Old 08-30-2020, 07:26 PM
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That gearing will give higher end speed. But no punch. I made that mistake when I did my first racing. Made the car easy to drive. But got killed in and out of corners. And would get caught or just runaway from on straight.

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Old 08-30-2020, 08:24 PM
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Large track you should be at 3.7. Smaller track high 3.8-3.9. At your current gearing youll bever get out of the corners and doubt you’d even get up to speed.

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Old 08-30-2020, 08:26 PM
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Originally Posted by herrokero View Post
Is it an old/used motor? And do you think it might have been overheated?
doubt it. Iíve overheated a motor and I know what that smells like
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Old 08-30-2020, 08:28 PM
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Originally Posted by STLNLST View Post
Large track you should be at 3.7. Smaller track high 3.8-3.9. At your current gearing youll bever get out of the corners and doubt youíd even get up to speed.
hmmm Iíll try a larger spur . I swore the car was maxing out almost instantly but I suppose it just wasnít even getting to top speed.
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Old 08-30-2020, 08:56 PM
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Originally Posted by illmatic94 View Post
hmmm Iíll try a larger spur . I swore the car was maxing out almost instantly but I suppose it just wasnít even getting to top speed.
That sound familiar. 3 summer of out outdoor in the last 4 years. Iím still finding gearing to be a bit of a mystery.
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Old 08-30-2020, 09:58 PM
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What size rotor do you guys run?
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Old 08-30-2020, 11:53 PM
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Most people is know that run usgt/21.5 run a final drive in the upper 3’s. But generally 21.5t motors are pretty gutless.

Last edited by riceball777; 08-31-2020 at 12:52 AM.
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Old 08-31-2020, 12:17 AM
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i'm running at about 40degree timing and 3FDR on a decent sized asphalt track that takes about 3-4secs to finish the straights.
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Old 08-31-2020, 04:06 AM
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65 on the end bell seams really high
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Old 08-31-2020, 05:35 AM
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Originally Posted by rko View Post
i'm running at about 40degree timing and 3FDR on a decent sized asphalt track that takes about 3-4secs to finish the straights.
3-4 seconds for straight, must be huge track
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Old 08-31-2020, 05:41 AM
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Get the motor down to a true 40 to 42 on a Motolyser. End bell marks can be off a lot. You get above those numbers and bottom end torque quickly disappears and when you couple that with excessive gear you get a car that won't get out of its own way.
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Old 08-31-2020, 07:42 AM
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Thanks for the replyís , i went out this morning on my street to test speed. I lowered the timing to around 40 and added a high torque rotor . That helped but after sleeping on it Iím convinced this motor is just slow. Or everyone was running boost. No other explanation to get walked on in the straight
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