Cam profile choice - Volvo B20B

Hofty

Seaman
Joined
Apr 17, 2020
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72
So the engine refurbishment project is well underway. I pulled out the camshaft and it appears that the profile is an "A grind type" (See attached specifications).

From forums it is understood that the A profile grind is suitable for a single carburetor engine but my engine has dual stromberg Carburetors so the question is then why would this engine have the A type and not a more aggressive cam like a B or C?

I'd like a decent power curve to get up on plane with a fully loaded boat (21ft Starcraft Chieftain) 4 adults 2 children and fishing gear (1200lbs) but also fuel economical for cruising. Not looking to go racing around but I feel like cam profile choice is important right now. I have not measured the cam lobes to see how out of spec (worn) they are as not entirely sure how many hours have been put on the motor since it was refurbished in 2008.

Any guidance or advice is appreciated.
 

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Scott Danforth

Grumpy Vintage Moderator still playing with boats
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49,602
the question is then why would this engine have the A type and not a more aggressive cam like a B or C?
because you are running a wet exhaust and the other cams are street cams with too much reversion.
 

Hofty

Seaman
Joined
Apr 17, 2020
Messages
72
So given that would it be best to maintain the existing Cam A profile?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
49,602
So given that would it be best to maintain the existing Cam A profile?
yes, assuming that is a marine grind. your marine motor does not share the cam with the automotive motors.
 
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