any of tha MAJOR engine builders can help u as posted abobe but...anything in crate form from summit or other warehouses i would have dissassembled and clearance checked,,that was rec from several race shops because of the practice of "slap it together and get it out so i can bill it mentality",if u want higher horse motor buy the parts separate,have your machine shop check ALL measurements and assembly yourself.or your knowlageble buddy's..you will save ALOT of money,,,probably half!
thats what i did with the hemi i sold prior to this car,,,as another poster said,,u can easily get into the 800-900+ range on pump gas,,,,its all in the heads and roller valve train...
when i got it back from marino's machine here all the bearing,rings,pistons,rods were all marked where they go...just like painting by the numbers,,,,,actually it was...
same applys to 425-500 horse motors...who test fired it on the dyno?what oil and additives,flat tappet??trust no one!!!lol.$$$