Both. Use a dyno to get a general idea of which is your best motor. If you have 2 that are dogs on the dyno and one that is good, dynos don't lie, the good one will be better. Say if you have two that are good, then you track test in practice (if you have time) to see which runs better on the track. That's what i'd suggest.
USVTA Member #211
Yokomo BD7 (Mod TC), Corally Phi '07 (VTA)
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