I've used the Orion 4800 lipo and it fits in the chassis with the top deck on. The only problem is that the Corally plugs that are used hit the body. There just isn't enough space under the body. This problem can be solved by making your own battery wire that's lower and is angled 90 degrees. There's not much room and I'd actually recommend getting a lipo with regular deans connectors. Try
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