Getting a 15lb truck to 40mph may be a bit of a chore. I think that 35 would be more realistic and practical.

In any event, you should prepare yourself for some fun.

As a side note and perhaps a piece of advise, if you are venturing into the unknown, it is usually better to err on the side of being conservative than getting things that are too hot. It really sucks when you put something together only to find that you can't run it the way that you want to, because of excessive heat.