F75 TO F90 conversion

[madharchod]

i think you are the smartest guy on planet ,the reason why no body has taken them to court is they have never done this as people are chicken to spend money on experiment ,now you have realized the parts are same vis A vic its not that company want to sell expensive engines they just want economies of scale during production ,so if you are clever like me you have time you find these things out sort few issues and hey presto you have bigger engines with less money

[acehiggy]

I like Nascar too!

madharchod is right ... this will work. The ECU will calculate the air flow and will adjust the injector pulse width to add more fuel to maintain the proper air/fuel ratio. Air flow is calculated using the MAP sensor, RPM, and air temperature. Fuel pressure is con*****ed to 40PSI with a fuel regulator dumping excess fuel back into the tank. Constant fuel pressure along with an accurate timing pulse delivers the proper amount of fuel to match the air flow. The oxygen sensor is used for closed feeback to adjust the air/fuel ratio to keep it around 14.7 to 1.

I am no expert on internal combustion engines but how does my Flexfuel car run on both E85 and gasoline? Or any mix of the two? I think because it is a closed loop control system (the ECU).

[madharchod]

mate i talk with some 40 years of experience under my belt ,so if iam not sure i wont comment but if i have done it i will swear by it ,that's it. case closed .
if some one out there wants to experiment iam more than willing to help out in the conversion

[SHMtroller]

madharchod, with my F75 efi '09 being out of warranty, I felt it was worth the risk to try removing the restrictor from the silencer assembly. The motor has performed as you indicated. Top end mph increased 3-4 mph. Anecdotally, the hole shot also seemed better. I did not change the prop as I was slightly over propped before (5500-5800). Now I run at 6000 rpm at my most used trim level (light load in boat), and 6100 trimmed way up. I have not hit the rev limiter. My question to you is about any issues you may have encountered after you have made the same modification? My motor has performed well thus far, just curious if you have any recommendations or concerns after having removed the restrictor on the f75.

Thanks

SHM