Here is an example of what I am talking about. It is an example for you to get some specs from as you do your research. I have no experience with this brand of crate motor. However, I have spent 10s of thousands of dollars with Summit Racing and have never been disappointed. Once in awhile the wrong part showed up but they made it right the first time I asked.
The reason I suggest you rebalance and blueprint any crate motor when new is I use my cars on track and I don't believe crate motors persay are dynamically balanced or carefully measured before assembly. Generally, crate motors as well as assembly line OEM engines are balanced mostly by selecting parts such as pistons, rods, etc. that match weight/ measurement specs and then assembled on a crank that has been pre-balanced.
Race engines need all the final assembly pieces balanced as a unit as well as the careful measurement of all the contact points such as crank journals, ring gaps, bearing sizes, etc. There can be significant differences in results between the two methods. But a carefully balanced and assembled engine will live a long happy life and stay together if stressed.
Street use simply does not stress an engine like 5 or 6 30-min high rev, hard as you can go, sessions in one day does.
I would ask around your area for a crank balance shop that you can work with. Let them know what you are thinking and get their opinion as well as the cost of working with a brand-new motor.
Ultimately, you might decide to not redo the crate motor because you are satisfied with the warranty and reputation of the vendor. In any case, you have some information to start with.
Free Shipping - BluePrint Engines Ford 306 C.I.D. 370 HP Dressed Long Block Crate Engines with qualifying orders of $109. Shop Crate Engines at Summit Racing.
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