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Got my rebuilt quadrajet back yesterday, slapped it on, took the boat for a rip, everything seems good. The guy that rebuilt it for me is coming back to do the fine tuning, but he asked me what rpm's the boat should be getting. I'm not sure. Any help would be great.

Merc 454 mag
23p ss prop
Did 62 on the speedo at 4500 rpms yesterday

For anyone with similiar problems with their boat falling on its face when getting out of the water, the quadrajet had a broken internal spring (not sure of the name) and a gasket that was ripped.

Also, since I'm still getting familar with engines, are the primaries the front two flaps? Should they be open when the boat is not running?

Thanks!
 

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They will be open when the boat was just shut off. Those are activated by a heated divorsed choke. with a COLD engine the flaps will be closed. When hot they will be OPEN regardless if the engine is running or not. The scondary flaps are the bigger ones in the rear. Those are activated by pressure.
 

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levie17 said:
Got my rebuilt quadrajet back yesterday, slapped it on, took the boat for a rip, everything seems good. The guy that rebuilt it for me is coming back to do the fine tuning, but he asked me what rpm's the boat should be getting. I'm not sure. Any help would be great.

Merc 454 mag
23p ss prop
Did 62 on the speedo at 4500 rpms yesterday

For anyone with similiar problems with their boat falling on its face when getting out of the water, the quadrajet had a broken internal spring (not sure of the name) and a gasket that was ripped.

Also, since I'm still getting familar with engines, are the primaries the front two flaps? Should they be open when the boat is not running?





You should run a 21p prop the motor has about 300 rmps left and dropping that pitch would get you 250 more. I had a 21p Cleaver on mine with the 330 h.p. 454 and ran 65 @ 4800 RPM. Good Luck!!!

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The 1987 454 Mag was a 330 hp motor. 1988 and up was the 365 hp version. Recommended RPM is 4200-4600. You are pretty much on the money, maybe spin it a bit higher with a light load.

Kurt
 
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