if i were you big-block, i would not buy the savage xl because all you need to get your new flux to xl length is the chassis plates and the rear dogbone. the best motor for your needs seems to be the 1520. it can handle 8s very nicely and is a real powerhouse. i've seen 18-20lb trucks run them with good temps.
if you are wanting both a standard length and a xl, then put the 1520 into the xl and keep the stock motor in the stock length truck. there is absolutely no need for more power if u run 6s with the stock motor.
also, if the truck came with the 2.4GHz radio, it WILL have the BP diffs and i have yet to ruin a BP diff on my xl length truck and trust me, those diffs take some serious abuse in my truck. heavy 40 series mashers on heavy beadlocks can be really rough on diffs, especially if you are doing standing backflips. the dogbones on the other hand, don't handle it so well. if anybody knows of any dogbones that are stronger than the HPI super heavy duty bones, please post a link to them.
