I don't know why mercury does that but Don t think it's fuel cooling because it's on one side of fuel rail. Optimax 250-300 has compressor water supply bypass fuel rail. 200 225 has water supplied from fuel railQuote:
Originally Posted by darkdream
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I don't know why mercury does that but Don t think it's fuel cooling because it's on one side of fuel rail. Optimax 250-300 has compressor water supply bypass fuel rail. 200 225 has water supplied from fuel railQuote:
Originally Posted by darkdream
Temp sensor is moved. Not replaced.
You are right yesterday I moved mine hopefully the good position. Thanks for all the reply'sAttachment 428240Attachment 428241
My 2005 250xs's have the fuel rail water hoses hooked up when I bought them
I thought the 1.1 update removed the sensor and the 1.3 update required the sensor be installed back in?? Can someone please confirm.Quote:
Originally Posted by darkdream
I have a 250 and just did what Joe told me. Only one option for 250
Thanks I hope somebody can confirm heard the same but not sure. Tried to get in contact to dbr by mail but think to busy. Don't know what happen if run temp sensor out when have to be in? Temp out is more rich? Dont want to kill my engine due a simple mistake...
You will be fine running sensor out.
Fyi that is not a true air intake temp sensor it's a coolant/water temp sensor. It's just there to give a reading too calibrate fuel mixture.
So in theory now that you removed temp sensor it should be more cooler because it doesn't have heat transfer from intake plenum now which should make engine run little richer.
If you have doubts pull couple spark plug before and after to read fuel mixture
It is an Opti. The computer will compensate for any rich (or lean) condition. The re-positioning of the temperature sensor is to keep the sensor in ambient air, not heat soaked by the intake manifold aluminum after a bit of time which gives the ECM inaccurate air temp data. That way the temp input data to the ECM will be the temp of the incoming air, not the temp of the aluminum of the manifold. This info according to DBR and common sense engine input/output sensor/ECU parameter knowledge.Quote:
Originally Posted by 2jz
Both the 1.1 and 1.3 recommend the sensor re-positioning for this reason. All the hype about the DBR tune (re-flash) is very subtle, if at all noticed without a dyno (adjusted to fit the message from DBR :rolleyes:), IMO. Just little tweeks like the sensor re-positioning, a higher rev limit, etc. are gained by the DBR tune. If you study the HP and torque curves of an Opti, you will notice max HP and torque well below the stock rev limit, so raising the rev limit accomplishes little to nothing. You engine should be propped to "OPTI"mize :D the max. HP and torque in that sweet spot or your missing the "boat":thumbsup:. Mother Mercury is hard to beat in the R&D - HP extraction game!:iagree:
I was impressed by the performance difference. This is real-world testing on a bass boat with a data logger. This test wasn't for all out top end. I did see an improvement with my big wheel top end numbers as well. Honestly, I haven't pushed it yet. Like mentioned, I prop for under 6k for topend.
https://www.youtube.com/watch?v=PHNB1ZkSRzU
I also tested the MadEFI flywheel. Look how the flywheel plus DBR would have impacted holeshot. I fish, so I made some necessary changes and the full impact wasn't seen.
https://www.youtube.com/watch?v=seBUTvtgusE
Thanks, I just placed the order;) great test movie hopefully it works also for me. Best thing is the new one is balanced for higher rpms and the stock flywheel not (what I heard)