A good GNCC engine you want to have somewhat high compression say 180 at least to run pump gas. You can run a higher compression than 180 & would make for a real good pulling grunt engine but you would need to use race gas. Anywhere over 210/240 compression will be surprizing how good it will pull but attention to fuel octain & ignition timming will be the rule.
Unless you know the engine real good inside, only way to be sure it will last is to pull it down & inspect it just like was already noted.
Been many championships lost because of not knowing a engine or who built it.
Neil