Serpent 966 - 1/8 Onroad brushless project

[othello]

Now on to the more challenging part of this conversion. How to fit a battery to this type of chassis? Since i'm using a 1100kv motor and as i want to reach around 45000rpm (Nitro onroad motors are close to this level too) i need to use 10s lipo cells using my trusted Kontronik Jazz 55-10-32 ESC. I mostly have red about 6s 1/8 on road conversions which used around 4000mAh. Well this corresponds to 10s 2500mAh in terms energy capacity.

I sourced 2 3s SLS 2200mAh lipos from a buddy and paired them with my leftover hyperion 3s 2200mAh which results in a 9s 2200mAh battery pack for testing puposes.

So this is what i came up with and how the car is setup right now using components i had in my parts bin. 2 3s Lipos (the green ones) are fitted under the top deck between the motor and the steering servo. And the 3rd one is laying on top of it. As i already mentioned this was for testing puposes only as i wanted to see how this car handles.


To offset the weight of the 2 lipos under the top deck which stick out more on the right side i placed the ESC on the left side of the top deck. This provides a perfectly balanced Chassis (r/l). A microsens BEC fitted directly in front of the third lipo provides power to the receiver and the steering servo directly from the 9s battery pack. This setup as seen here wheighs 2600gr (5.73lbs) without the body.


Chassis with protoform P909 body

[othello]

Although the outside temperature showed minus 10°C (14°F) i had to give the chassis some rollout.

This is the video of its first test run

With this kind of driving i used around 100mAh per minute. Battery setup will change as soon as i'm 100% sure which lipos to use. As of now i think i can perfectly fit 2 5s turnigy 2200mAh (10s in series) below the top deck with lifting it a few mm.

I already painted the body and it came out pretty much as i wanted it to be ...


Right now my place is covered with snow and it's still too cold outside to conduct more test runs. But i will update this thread as soon as i'm able to get more test runs.

[Jony Nitro]

Impressed with the 9s in there,and that you got it all in there, max mph?

[lutach]

That's a nice set up you got going on there.

[othello]

With 9s (around 37500rpm) and 18t pinion serpent's drive calculator puts it at 98,5km/h (61mph). With 10s top speed should be 110km/h (68mph).

I made a second test run yesterday and both the front and rear belt broke due to stones laying around everywhere. Lesson learned. I must protect the belts with lexan pieces.