Performance on '73, 21’ Chiefton.

[Always Broke]

I’m restoring a Chiefton, the motor is next on my to do list and I’m starting to get a little worried about performance, I hope you folks tell me my worries are for nothing. I bought the boat to restore and never had it on the water. I’ll probably post this same question in the Mercruiser forum to cover all the bases. I always had smaller boats with either inboards or outboards with fiberglass hulls, except back in the 60’s and 70’s my family had a 26’, wood, Chris Craft Caviler with a 283 Chevy and a strait inboard. The boat ran like a bat outta hell and would run close to 50 MPH at WOT, we even pulled 10 skiers with it once, ahhhhh the good old days of high compression and good gas. The thing that got me going is I always check the Mercruiser forum for tips and advice while I was freshening up my out drive and see a lot of posts from folks who have around the same size boat 2500# dry, a lot more ponies then my 165 HP rated 250CI six banger, and they are always complaining about lack of power and not being able to get out of the hole let alone pulling a skier. I plan on using my boat for fishing and over night cruising, I’m out of the go fast stage but still got enough kid in me that when I kick the boat in the butt I want er to get up and go, not wallow around like a Manatee. A lot of boats were sold under powered to keep the price down, do I have one of them? I also have not been able to find what kind of compression ratio this motor is running, good gas was still around in 73’ any idea? I probably wouldn’t go as far as to put a V8 in it if it is under powered, it sounds like a good running motor and I hate to get rid of it if it ain’t broke. I would try to make the old 6 breath a little better, it has a manifold that is able to accept a 4BBL with a block off plate and a 2BBL on it and I can always make a little noise with a through hull exhaust.

 

[Always Broke]

Re: Performance on '73, 21’ Chiefton.

I got some good answers in Mercruiser forum, except for my compression ratio. Any help there? Does anyone here have the same type boat and motor

 

[perchman]

Re: Performance on '73, 21’ Chiefton.

Hi there!!<br />I have a 75 chieftain which is ~23 ft. <br />It has a 165 6 banger in it, and I happen to have the manuals. <br />It is likely that the engines share the same specs. <br />Compression ratio is 8:1 and rated cylinder pressure is 140 PSI.<br />I believe you will be surprised at the getup and go of your boat with the existing engine. <br /><br />Your project is interesting to me as I followed a similar path starting back in 2001 when I purchased my project Chieftain. I am close to having it finished but lost motivation for the last couple years and she has sat in my barn lonely. I started thinking about how nice it would be fishing in that boat this year and it got me googling, which led me to this Forum tonight. After reading some of the postings including yours, it has fired me up to try and finish what I started. <br /><br />Let me know if you need more engine information.<br /><br />B.R.<br /><br />Perchman