The good news and then the bad

[supracalifragilistic]

The good news is I finally finished the rebuild on the 454. Dropped it in the boat(1989 saltare w/ 454) and after realizing i had the fuel pump in upside down got it started (sounds really good) compression is only at about 120 on all but 2 cylinders (6,8 i believe which are only at about 100) but it runs and runs fine. tops out at about 43 mph.
The bad it is having a hard time starting. i turn the key it cranks stops cranking and then will usually start( i hold the key the whole time) not sure why its having such a hard time turning over.
More bad... while the transmission isnt engaged it goes into reverse with no problems the second i engage the transmission the throttle seems like it is stuck and wont go into reverse...(neutral and forward work great).... any ideas?
problems hard to start and wont engage into reverse.

also the previous owner added a holley EFI unit, which a mechanic told me he has had nothing but problems with.... Any input? good or bad?

[Jetlink]

As for the transmission issue, might be that the cable is binding up along the way. Just my first thought on the matter.

[CornRickey]

So it cranks but doesn't fire till you let go of the key (letting it go from start to run)?

[michael hunter]

Sounds like you have what we used to call [heart attack start] Check your battery connections, solenoid and cables. Look at the cables closely they will sometimes corrode inside you can use a set of jumpers to go from battery - to block and batt + to solenoid to test them.

[wotan2525]

Also check your timing.... Especially with a rebuild it could be a few degrees off which will make it hesitate on start.