1974 55ph chrysler

[tyst67]

i just got the motor from a friend and i dont know much about it. the model number is 557bg. There are some 55hp chryslers that have twin carbs and i was wondering if i can get a intake so that i can put twin carbs on this? I am also wondering if i can upgrade this to a 65hp! i cant find much on this motor but the newer model has a better ignition system on it, is it possible to make a conversion?

 

[Nordin]

No you can not put twin carbs on your engine. The twincarb 55, 60 and 65Hp engine is a complete different engine then your 55Hp, The powerhead, middleg and gearcase is completly different.

To upgrade an OB never give you more then 2-3 or maybe 4Hp. To upgrade from 55Hp to 65Hp.........no. Buy a 65Hp engine instead.

 

[tyst67]

Are the 55hp motors that i have powerful?

 

[Nordin]

Well, Chrysler rated at the crankshaft in those days. In about the late 70,s or early 80,s they change to rating at the prop.
I think Merc and OMC rated at the prop in early 70,s BUT I am not sure.
Chrysler engines are strong because of much displacement with big bores and short stroke.

 

[jerryjerry05]

Your 55 was/ is one of the best running and most dependable of the Chrysler line.
As far as power you probably have about the most power to weight of any outboard.
Just remember it's a 55 and you can only do so much with a 55.

The 82 or 83 85hp set a speed record of 82mph. Not sure if it still stands? Way faster than I want to go.