Chrysler 5 hp 1970 (52ha) - how many hp?

[Oversea]

Hello!
I know that the topic sound stupid. You will all say,"-its a 5 hp.."
But i've done some research and found out that this egine has the same disp (8,99) as the 6 hp model.
At the same time i found a guy looking for a carb (model md145a) for his Chrysler 7 hp and it has a bigger disp (cc)..
My 5 hp has this kind of carb. This gets me to the question.

If my 5 hp have a carb for a 7 hp, but egineblock etc for a 6 hp. Shouldnt my 5 hp deliver atleast 6 hp?

The beauty is in the garage at the moment getting fixed up after being in a barn for the last 20 or so years. Changing impeller, gasline, sparkplugs, cleaning carb, etc).


/ question from north of sweden

 

[Frank Acampora]

Re: Chrysler 5 hp 1970 (52ha) - how many hp?

That is actually a very difficult question to answer.

Manufacturers frequently will take a block with the same displacement and up-tune or de-tune it by changing port timing to deliver a higher or lower horsepower. Carburetion, especially with these smaller engines will make very little difference.

HOWEVER: Sometimes they simply re-badge an existing engine. An example of this is the Sears Gamefisher 7.5. It is actually a Force 9.9 with no changes other than the name and capacity plate. In the repair manuals there are a couple of examples (especially where Chrysler was sold to Brunswick and renamed Force) where a larger engine was rebadged to a smaller horsepower and even where a smaller engine was simply rebadged to a higher horsepower.

So: Does your engine make more than 5 HP? Who knows? The only certainty is that it will not deliver 7 or more.

 

[Oversea]

Re: Chrysler 5 hp 1970 (52ha) - how many hp?

That is actually a very difficult question to answer.

Manufacturers frequently will take a block with the same displacement and up-tune or de-tune it by changing port timing to deliver a higher or lower horsepower. Carburetion, especially with these smaller engines will make very little difference.

HOWEVER: Sometimes they simply re-badge an existing engine. An example of this is the Sears Gamefisher 7.5. It is actually a Force 9.9 with no changes other than the name and capacity plate. In the repair manuals there are a couple of examples (especially where Chrysler was sold to Brunswick and renamed Force) where a larger engine was rebadged to a smaller horsepower and even where a smaller engine was simply rebadged to a higher horsepower.

So: Does your engine make more than 5 HP? Who knows? The only certainty is that it will not deliver 7 or more.

Thank you for the respons. Great info. I've tried to search info on these 5 hp but there isnt much out there. These 5 hp chryslers seems like odd ones. Most info out there is on the 6 hp version. Looks like they upgraded the 5 hp to 6 hp after only a few years, in the early 70's. Anywho, its gonna be fun to se how she works when the season starts in a month or so.

 

[iCam]

Re: Chrysler 5 hp 1970 (52ha) - how many hp?

That totally makes sense Frank. My thought on this may be totally off the mark, and I want to be corrected if I am wrong so I stop spreading around scuttlebutt if I am.
My understanding was that before a certain year( and I have no idea when) the manufacturers measured HP where they wanted (ie at the engine or at the shaft). When another company re-badged or came out with a new line they listed it as whichever HP that they wanted.
I wanted to say mid 70's or early 80's they standardized it to measure hp at the same place (and I forget at the moment whether it is at the shaft or engine). So a 5 hp from the 60's is not the same HP as a 5 hp from the 90's.

Am I totally off base on this?

 

[Oversea]

Re: Chrysler 5 hp 1970 (52ha) - how many hp?

ICam

Would be really interesting to know exactly what year they standardized.
it I doubt this, but they could have rated my engine higher a few years later because of another type of mesaure system. Even if it's unlikley, it's still possible that the 5HP became the 6HP. On the other hand, it's also possible that the 5HP became the 4HP engine at this point.

Is it possible to measure HP these days. Like at a repair shop or something?

 

[mercuk]

Re: Chrysler 5 hp 1970 (52ha) - how many hp?

That totally makes sense Frank. My thought on this may be totally off the mark, and I want to be corrected if I am wrong so I stop spreading around scuttlebutt if I am.
My understanding was that before a certain year( and I have no idea when) the manufacturers measured HP where they wanted (ie at the engine or at the shaft). When another company re-badged or came out with a new line they listed it as whichever HP that they wanted.
I wanted to say mid 70's or early 80's they standardized it to measure hp at the same place (and I forget at the moment whether it is at the shaft or engine). So a 5 hp from the 60's is not the same HP as a 5 hp from the 90's.

Am I totally off base on this?

I'd agree with that statement. I got a feeling it was "standardized" around about the mid 80's when all the jap stuff starting coming out and they were all done by h/power or torque at the prop shaft instead of crankshaft.

Obviously if you take a reading from the prop shaft is going to be a lot more accurate. It's the same with car's; you can take a torque/ h/power reading at the wheels or like some manufacturers, from the c/shaft and clearly from the wheels its going to be a more realistic figure as you lose power through transmission, p/shaft, d/shaft etc etc.

 

[iCam]

Re: Chrysler 5 hp 1970 (52ha) - how many hp?

Well I googled it and guess where I found the answer on when they standardized it...... Here on iBoats. Here is the link;
http://forums.iboats.com/showthread.php?t=11883

If you read the link it has a +/-10% thing in there, BUT I think in your circumstance (on your older engine), I am leaning on Franks answer. He is muuuuuuuuuch more smarter on boats than I am.