repowering from a 350 to 454

lime4x4

Lieutenant Junior Grade
Joined
Apr 25, 2007
Messages
1,040
What is still usable from the 350 engine? I know the carb and intake manifolds are different along with the water pump.Can i reuse my brackets, power steering pump, alt, dist and rest of ignition system. Also will the throttle cables and linkage be usable yet?
 

bomar76

Lieutenant Commander
Joined
Jun 27, 2002
Messages
1,963
Re: repowering from a 350 to 454

Not a lot of info as to exactly what you have, but here is some general info.
If the 350 was a 4bbl, it will be fine on the bigblock, probably a 600 cfm but I doubt you are planning on winning any races anyway.
SBC's and BBC's share the same distributor.
Ignition is the same.
Linkages should be the same.
Brackets, dunno.
Crank pulley will be different.
Alt and PS pump are the same.
Starter may or may not be the same....depends on vintage of each engine and flywheel used.
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: repowering from a 350 to 454

What outdrive do you have? Better be a Bravo, in reallity. Mercruiser did use the Alpha I on the 454 Mag in 86 & 87, but found out they would hold together and in 88 the Bravo drive was introduced.
If you have an Alpha drive, you will need to change the gear ratio to a 1.32:1 from the 5.7's 1.50:1
All you brackets that hold things like the alternator, PS, etc will not fit on the BB. Different hole locations.
The 7.4 while it will have the same type ignition system the ignition module is different from the 5.7.
 

lime4x4

Lieutenant Junior Grade
Joined
Apr 25, 2007
Messages
1,040
Re: repowering from a 350 to 454

looks like i'll be looking for a donor boat
 
Top