Will a 2.3 omc cobra outdrive work with a 3.0 omc cobra engine

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bullit_09

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Hello, I just purchased a 1988 sunray continental with a 3.0 omc motor and it had a 3.0 omc cobra outdrive that was stolen. I found a 2.3 outdrive for a killer deal and picked it up all the seals are good oil was nice and clean and no metal deposits were found in gear oil. Now I found out that the 3.0 outdrive is a 1.71 gear ratio and the 2.3 is 2.00 I found out that I will be loosing 7 mph but will it cause any other ill effect on the motor or outdrive if they are mated together.

Thank you

Gabriel Bergeron
 
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bullit_09

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Re: Will a 2.3 omc cobra outdrive work with a 3.0 omc cobra engine

no one has any input on this ?
 
RogersJetboat454

RogersJetboat454

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Re: Will a 2.3 omc cobra outdrive work with a 3.0 omc cobra engine

The higher ratio outdrive may cause your engine to over-rev at WOT if you used the same pitch propeller as what was installed on the stolen drive. Outdrive gear ratios are usually matched to the engine, based on the engines output at such and such an RPM.
You may be able to negate this by using a higher pitch prop, but it may not be perfect. Either hole-shot, or WOT performance may suffer if it isn't right.
 
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HT32BSX115

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Re: Will a 2.3 omc cobra outdrive work with a 3.0 omc cobra engine

RogersJetboat454 said:
The higher ratio outdrive may cause your engine to over-rev at WOT if you used the same pitch propeller as what was installed on the stolen drive. Outdrive gear ratios are usually matched to the engine, based on the engines output at such and such an RPM.
You may be able to negate this by using a higher pitch prop, but it may not be perfect. Either hole-shot, or WOT performance may suffer if it isn't right.
Click to expand...

Yes,

You WILL have to replace your propeller with an approx 2" higher pitch prop. I.E if you currently have a 17p prop installed, you'll need to go to a 19p prop etc........

Your performance difference will probably be negligibly poorer......but it will still "work".

Propellers have a rather narrow range of RPM vs speed where they operate most efficiently.

Get outside of that range too far and you lose *some* performance.

You probably won't notice a huge difference.

Cheers,


Rick
 
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bullit_09

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Re: Will a 2.3 omc cobra outdrive work with a 3.0 omc cobra engine

RogersJetboat454 said:
The higher ratio outdrive may cause your engine to over-rev at WOT if you used the same pitch propeller as what was installed on the stolen drive. Outdrive gear ratios are usually matched to the engine, based on the engines output at such and such an RPM.
You may be able to negate this by using a higher pitch prop, but it may not be perfect. Either hole-shot, or WOT performance may suffer if it isn't right.
Click to expand...

Thank you for the reply the pitch on the stolen drive was 17 and on the 2.3 I purchased it also came with a 17 pitch prop between the 3.0 that revs at 4600rpm and the 2.3 thats revs at 5200 rpm I believe the pitch difference would only need to be +1 to be able to correct it ? since the 2.3 came with a 17 pitch prop like the 3.0
 
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bullit_09

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Re: Will a 2.3 omc cobra outdrive work with a 3.0 omc cobra engine

HT32BSX115 said:
Yes,

You WILL have to replace your propeller with an approx 2" higher pitch prop. I.E if you currently have a 17p prop installed, you'll need to go to a 19p prop etc........

Your performance difference will probably be negligibly poorer......but it will still "work".

Propellers have a rather narrow range of RPM vs speed where they operate most efficiently.

Get outside of that range too far and you lose *some* performance.

You probably won't notice a huge difference.

Cheers,


Rick
Click to expand...



Thank you Rick!

I will run the 17 pitch prop to try it since I have two that were spares and if i see any over rev I will then sell them and get 19 pitch props, thanks for helping

I am new on this forum and so far really like, it has lots of knowledgable people on here and not to harsh to newbies :p

Thanks


Gab
 
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