you could write a novel on this debate.......short answer, the builts make more power than the crates. The crates will not create as much power at higher rpm's so they must run a lower gear. They just run out of power. That's why most series/tracks give the crates a weight break. They make less power, but they cost WAY less. The 602, 604, and the act crate all cost much less, and they have pretty much saved late model/limited late model racing in north america. Look at the limiteds, pretty much all 602's with a weight break. Late models, pretty much all 604's with a weight break. Act, if there is one built at kawartha, i don't know about it. Maybe there's one or two, but again the weight break. Oscaar, allowing crates with the weight break. The reason? It's saving racing from a cost point of view. I guess that wasn't so short, but trust me, there's tons more to say.
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