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Go Fast, Turn Left
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Apparently you can get away without it.

BUT.......

I heard that Charlie from Novak strongly suggests you use it. It does not have to be as big as the factory cap for 4 cell racing. I guess it keeps things running a little smoother and cooler.
 

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There is more to it then just the Cap. I have posted this before but here is Charlie's reply to my email again:

I don’t think the 4 cell GTB uses a smaller cap. Who told you that? None of the one’s we’ve tested, or passed around the building for approvals have a different cap. We intend to use the same one as it simply provides added performance.

You probably could use a smaller cap, but you loose some performance and gain some heating.

The Power Cap is there to help the ESC cope with Ripple Current effects that are created by high speed ESC switching. Anytime the ESC is switching on and off, the power wants to keep flowing, the cap catches this and feeds it back to the motor when the mosfet turns on again. So it charges and discharges EVERYTIME the ESC switches. This is all the time with BL, so a good cap is very important.

The circuit board has what are called, “transorb” diodes. These items are like voltage “clamps” if you will. When a big spike comes through the system (usually from the motor), the transorb clamps on to prevent the spike from damaging the ESC and the cap. It kills the spike essentially. If you do got to a smaller cap, you have to KEEP the transorb board. Again, we don’t recommend smaller caps.

 

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McLin said:
There is more to it then just the Cap. I have posted this before but here is Charlie's reply to my email again:

I don’t think the 4 cell GTB uses a smaller cap. Who told you that? None of the one’s we’ve tested, or passed around the building for approvals have a different cap. We intend to use the same one as it simply provides added performance.

You probably could use a smaller cap, but you loose some performance and gain some heating.

The Power Cap is there to help the ESC cope with Ripple Current effects that are created by high speed ESC switching. Anytime the ESC is switching on and off, the power wants to keep flowing, the cap catches this and feeds it back to the motor when the mosfet turns on again. So it charges and discharges EVERYTIME the ESC switches. This is all the time with BL, so a good cap is very important.

The circuit board has what are called, “transorb” diodes. These items are like voltage “clamps” if you will. When a big spike comes through the system (usually from the motor), the transorb clamps on to prevent the spike from damaging the ESC and the cap. It kills the spike essentially. If you do got to a smaller cap, you have to KEEP the transorb board. Again, we don’t recommend smaller caps.

Thanks Mclin ,

I'm going to keep my stock factory cap. exactly the way it came from the factory !! ,,,,,, Even thought us racers think we have a better idea , it usually boils down to there's a very good reason why it was engineered that way ,,,, Don't fix it if it ain't broke ! THANKS AGAIN :thumbsup:
 

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I guess I just cant see the value of not running the cap :confused: The weight diff is hardly worth mentioning.
From everything I read there is no performance edge gained by not using a cap but there seems to be some benefits from using one.
So could someone post the reasons for not running a cap?
 

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All extra weight is worth mentioning if your driving skills are close to perfect and your car is setup well. Most people aren't that good and neither is there car but some like the above mentioned are and they don't run it and I am sure that weight is the only reason. The fact that you don't need it for 4300 or 13.5, which has been proven by people that are the fastest, leaves you to ask why run the thing?
 

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Sometimes just finding a place to mount the thing is a chore as well.. I kept mine But Ill admit just the bulkiness of the thing is a PITFA to deal with..
 

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Tell me what caused this I put a brand new GTB 4cell and 4300 motor in Sat morning and ran all day!!!!!I went out to make a run and it just stopped on the track!!Came to the trailer and turned it off and back on and it work few secs latter it stopped again!!!!I unpluged the wire harness to the speedo and pluged back and never stopped again!!!!I checked the heat on the motor was 155!!!!!!!Hacksaw
 

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Saw, I am not sure at what temperature the GTB will thermal but if you did all that and the motor was still 155 it sounds like that is what happened. OR it could have been a bad connection on one of the pins in the motor plug and taking it on and off cleaned it up.
 

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Hey Lin It did it again Sat and I just un pluged the wires from the motor and pluged back up and reset speedo!!!!!!!Ran all night after that!!!!!!!!Hacksaw
 

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hacksaw said:
Hey Lin It did it again Sat and I just un pluged the wires from the motor and pluged back up and reset speedo!!!!!!!Ran all night after that!!!!!!!!Hacksaw
Hacksaw check the pins on the white 6 wire harness plug. I've seen them push back before and cause a few problems.
 
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