It's quite hard to tell from a photo since your camera will try to expose the chassis wrongly (make it too bright) which can make it look more like carbon. You certainly don't NEED a carbon chassis to compete at all - from my personal experience the Losi XXX chassis was noticably softer in plastic guise, but both B4 chassis (carbon and plastic) are stiffer. I've never driven a carbon B4 since they came out after my car, but i swapped vickys carbon chassis to a plastic one in the vain hope it might have been easier to drive - couldn't see a difference that's for sure (wallop bang)
I'd not worry about it - if you can get a replacement chassis then that's great but running it like it is probably won't make much difference.
I think the latest kits have the Cragg car on the front? I got my B4 in about 2003, so it's been a while since I got a new one
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