Make sure you yank the GP's or make sure the injector line nuts are loose when cranking over the engine by hand with the breaker bar. I've not personally had it happen(Thank the gods, I'd be posting this from a cemetery most likely) but other here with infinitely more experience than I have reported an engine starting in this manner.

That could be bad.

No compression also makes it easier to crank over and easier to hit the right spot without going past it.

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617 swapped Toyota Pickup, 22-24 MPG, 50k miles on swap