Unless it's changed, the Tempest is the fastest in level flight among the prop planes. Of course, this is only true at certain altitudes. Again, if it hasn't changed, 6500 feet was max speed in a Tempy, and nothing will catch it. Know your plane.
That said, the LA 7 should be perked, as any of the top speed fighters should. I don't know why it has escaped the perks so far.
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