1981 305 Crusader Engines Rpm

rperla

Seaman
Joined
May 21, 2005
Messages
62
Does anyone have these type of engines and/or know what is the approximate safe engine rpm? When I get to 2500 rpm it sounds as if the engines are beginning to labor. I have twin engines with direct drive on a 30 foot Chris Craft.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,082
Re: 1981 305 Crusader Engines Rpm

Well,......... I don't have the specs on Your particular Motors,..........<br />But,.....<br />A SBC is a Small Block Chevy,........... Their All somewhat the Same....... Your 305s come from a Large Family......<br /><br />In order for those motors to be Not Laboring,.....<br />They have to be Able to reach a WOT rpms of 4400/4800rpms.............<br />If Your Boat Can't reach these #s,.. Flat Out Gittin' It....... Your Laboring your motors All the Time.....<br />If your motors,+ props will allow peak rpms in the beginning of the season,+ your hull gets Nasty by mid-season,....... <br />You'll be Laboring your motors.......<br />Put Too Big a prop on them for the thought of Extra gas mileage,+ Your Laboring the motors All the time,....... <br />And, will Probably Blow them Up before their time.......<br /><br />So,................ What IS your present attainable rpms at WOT,..???......
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: 1981 305 Crusader Engines Rpm

"ASK AND YOU WILL RECEIVE, SEEK AND YOU WILL FIND, KNOCK AND THE DOOR WILL BE OPENED"<br />
Don't bet on it. This forum is on boats ...... Lord only knows what you will find/receive/get opened..... :p ;) :D
 

Stinger313

Cadet
Joined
Jul 27, 2005
Messages
29
Re: 1981 305 Crusader Engines Rpm

At 2500 that boat isnt even on plane yet.I have a 33 Carver(12,000lbs)and I run very well at 3100 to 3300 rpm.I would try to push it up and plane it out.If you are running that at 2500 all the time you must be burning alot of fuel. Good luck I this helps
 
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