Yammie 250/300 offshore ?

[AEW]

Looking to mount a Offshore 4.2 250hp on a Larson FX2020 and was just bench racing with a couple friends and we got looking at the specs for the 4.2 motor, seems the 225-250 and 300hp have the same compression/bore and stroke, etc.

Does anybody know what the differences are?

And can you change engine components to go from a 225 or 250 to a 300hp?

This is what happens when ya get a couple old drag racers together..

TIA

Al

 

[boscoe99]

Re: Yammie 250/300 offshore ?

The differences between the F225, F250 and F300 Offshore models are (1) data plate identities (2) cowling stickers and (3) ECU's.

If an F300 ECU is installed on an F225 then the F225 is the equivalent of the F300.

With the F300 ECU installed the minimum octane requirement changes from 87 to 89 octane.

 

[AEW]

Re: Yammie 250/300 offshore ?

Thanks, while I expected a bit more, it's nice to know one part does it.
Does the motor need to be reprogrammed or does the ECU do it by it's self?

 

[99yam40]

Re: Yammie 250/300 offshore ?

ECU is the program (Computer)

And is a little bit expensive

 

[boscoe99]

Re: Yammie 250/300 offshore ?

Yes, list price is $2168 for the ECU. It is cheaper to buy the F300 in the first than it is to upgrade either the F225 or F250 to the F300 configuration. Not to mention that having an F300 ECU on an F225 or F250 might effect the warranty on the basis that the motor will have been modified.

 

[AEW]

Re: Yammie 250/300 offshore ?

A little bit..hehe..a quick search comes up with about $1700 or so.

Have to think on that one for a bit.

And there is the warranty issue, plus the boat was rated for 250, just an old drag racer doing a bit of bench racing.
Thanks much.

Al