Quote:
Originally Posted by nelsmar
Ill say right now that yes you can tune this with the stock sensor. The OEM ecu uses the MAP sensor to decide the pressure differential between the manifold & atmosphere with an idea that the fuel pump is pushing a specific fuel pressure. This is simply to calculate "estimated" injection time for ports which is already inaccurate as the fuel pressure in the rails is going to drop if you start using heavy port... You realistically would only be maxing the MAP sensor out for a short RPM window and this could be "hacked" into the MAF scaling or even better a custom map that compensate the fuel pressure once you hit maximum manifold pressure that can be read.
Vortech's MAF housing is very clean and on the stock pulley there is very little turbulence and the car can be tuned 100% on MAF tuning alone and push the car nicely power wise. If you were on higher boost and you start passing iirc 4.8v or so the MAF tends to lose some accuracy and I end up switching to a hybrid speed density tune so that way i can get a little more accurate load calculation... You would only get somewhat close to this in very cold weather.
And if you are using pump gas you will likely be using MOSTLY direct injection so even if for an example you were using a lot of port say... 20%? and your injection calculation was off due to no map reading and that skewed your fuel quantity buy say.... 10%? thats 20 * 0.10 = 2% fueling error. Thats pretty minor... You already see fueling errors like that when running heavy port due to fuel pressure drop & even inconsistencies from the OEM injectors. Just as an FYI you can basically run that much boost on 100% DI. You would be pushing the DI system pretty aggressively and a little more than you should but it could run. Your tuner is likely only going to run 5-20% port injection at that boost level at redline on pump gas.
If it was my car I would get a map sensor that is large enough and do it right the first time but you really are only barely pushing past the open sensor capabilities. And the MAF from Vortech I would say is as clean if not more clean than the OEM airbox.
tldr; Yes its possible and can even be considered safe to use the stock sensor. I as well as many others have done this on a number of kits that have a clean MAF reading.
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Thank you. Take me some time to try to understand things you said. hah.
So if it is safe to use factory sensor now, is it measn it is going to be safe to use it in the future at any situation? For example if I go track and keep the engine at high RPM for a long time? I can understadn that the error is minor, but if I have a choice to use a 3bar sensor, I would rather use it, especially I have already purchased one. Also, manufacturer warranty is another concern.
I have contacted EFI Logics and they told me that they will try it again with 3bar sensor after the tuner come back this Monday. I hope they will not let me down. I have heared a lot of good things about them.
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