upgrade F75 efi to F90 efi

[pia66]

upgrade F75 efi to F90 efi

Please,<br />i am trying to upgrade my new F75 efi to a F90 efi ( 2005 model).<br />I have changed the ECM ( engine control module) but i dont have any more power !<br />Perhaps, i need to tune the stop throttle sensor position screw.<br />Does somebody have any information about that ?<br /><br />Exept the ECM, all thez other parts are the same for the F90.<br /><br />thanks in advance for your help.

 

[Silvertip]

Re: upgrade F75 efi to F90 efi

Re: upgrade F75 efi to F90 efi

Have you checked camshaft part numbers, cylinder head part numbers (the complete head, not just the casting number) as well as fuel injector part numbers. While the ECM may have the same base part number, but it may require programming for a 90. It's generally not just a simple matter of swapping a few parts to get higher horsepower even though the engine displacement is the same. On four strokes its cam, comapression, carburetion (or EFI in this case) and intake and exhaust tuning that makes horsepower. If it were that simple, manufacturers would sell very few of the bigger engines -- people would buy the smaller motor and simply upgrade them. The swap can obviously be done, but the cost is generally much higher than buying the 90 over the 75.

 

[pia66]

Re: upgrade F75 efi to F90 efi

Re: upgrade F75 efi to F90 efi

HI, I agree with all these arguments but I have checked all the parts number and only the ECM changes between these two engines. I by a ECM of F90 (600 $$US it is more than the difference in price between the two engines). But without result.<br />does somebody have an idea ?<br />many thanks

 

[Silvertip]

Re: upgrade F75 efi to F90 efi

Re: upgrade F75 efi to F90 efi

I didn't do an extensive search but although the cylinder head assembly part numbers are the same for the 75 and 90, I find it odd those numbers do not include the camshafts, nor are they even listed. Since these are major contributors to power, isn't it odd they don't show them? Wonder why? But then like I said, I didn't do an extensive search. I didn't check the intake manifold and throttle body either, or injector pumps and injectors.

 

[rodbolt]

Re: upgrade F75 efi to F90 efi

Re: upgrade F75 efi to F90 efi

I looked today a bit. seems the injectors changed as well. the 75 and the 90 take different injectors.

 

[pia66]

Re: upgrade F75 efi to F90 efi

Re: upgrade F75 efi to F90 efi

NO, rodbolt.<br />The injectors are the same. And i think that i have checket all parts.<br />It is very curious for me.<br />Perhaps, my engine is now a little stronger but the speed of my boat is the same ( rpm max 5700).<br /><br />It is now a challenge for me to try to determine which are truths difference between the F75 and The F90.<br />I study with much interest all your opinions on the subject.<br />Many Thanks

 

[rodbolt]

Re: upgrade F75 efi to F90 efi

Re: upgrade F75 efi to F90 efi

with just 15 HP its not going to change much. you need a test wheel ore better yet some dyno runs with both ECM's. did you check the part numbers for the exhaust compoments as well ?

 

[pia66]

Re: upgrade F75 efi to F90 efi

Re: upgrade F75 efi to F90 efi

Yes , i have checked the exhaust compoments.<br />but I do not give up and I continue my investigations.<br />thanks you for your help.<br /><br />now i know that it's not easy to upgrade en engine.

 

[franck2b]

Re: upgrade F75 efi to F90 efi

Re: upgrade F75 efi to F90 efi

Salut Pia.<br />Alors tu sévis là aussi!!!<br />Remarque en anglais ça oblige à réflechir.<br />Là tu m'interesses vraiment avec ton "outboard yamaha diagnostic system".Pas moyen de le trouver sur la mule et pas smoyen de déplacer mon concessionaire local : il bisque, parce que pas acheté chez lui!!!<br />C'est vrai que Bastia-Marseille à 2000 tours faut que je parte maintenant.LOL.

 

[pia66]

Re: upgrade F75 efi to F90 efi

Re: upgrade F75 efi to F90 efi

Please franck2b, can you write in English on this forum so that all our friends can understand. It is a little a question of courtesy.<br />Thank you by advance.