Best all around engine for oval and off road..
v spec
or
21 plus 5

id go with the 21 plus 5

RB C5BB

i agree the c5bb is better then those two choices ,but out of those i would choose the 21-plus [8D]

If your running on an oval you need an engine that can rev high without blowing up. For this i would recomend the v-spec with a set of ceramic bearings. You will still have some great bottom end, but it will still rev nice and high.

If you want something that's gonna last longer than a couple/few gallons, go with the Nova. The two engines are pretty close in terms of power. I think the driver would make for of a difference that the difference in power between the two engines.

i have seen both of these engines go and they are both very good.having a v-spec my self i am very impressed with the mill.one of the guys at the local track just got a plus 21-5 and it goes very well.they are both evenly matched power wise and are both really great engines.either one you cant go wrong,but for arguments sake i am gonna say V-SPEC!

They do have a difference in economy!!!!!!!!!!!!!!!

I hate to break this to you guys but honestly, the top of the line engines from all the top manufacturers are pretty even, you would be hardpressed to really see a difference between two engines that are properly tuned.
I hear people raving about the C5 BB or C6BB yet Rody Roem, the guy that designs the RB engines admits that the WS S7 series is just as strong as the C5/6 series.
they just deliver power in a different way, suitable to different conditions.
Now reliability is an area where you can really make bold statements because some brands are just plain more reliable and durable than others.
in my experience, the RB's seem to have the best build quality but that's another subject .