| But most race cars are setup for MAP. The simple problem is that MAF sensors are extremely sensative to turbulence, and besides that they have larger space requirements. The bottom line is that while most aftermarket ecus can in theory use a MAF for metering but they do not. In my case I want to mount my Air filters in the orginal intercooler locations, and do not want to keep the MAF for space saving reasons. Now as far as accuracy of the MAF versus the MAP. This is only one sensor a good ecu uses, other sensors that can used to accomplish what a MAF does especially a generic Hot Wire MAF does, such as Air intake take sensor. Now you are aware that factory ecu uses the narrow band o2 for A/F feedback for low rpm drivability, so the factory ecu uses an inaccurate narrow band ecu right while a aftermarket ecu would use a superior wide band. Looking at the voltage lookup table on narrow band ecu you know that there is only 1 volt swing and that accuracy is really only focused on a afr of 14.7. For example .900mv-1.000mv is only 12.5 thus the factory o2 can never be used to do high RPM correctionos while an aftermarket o2 can. Now lets talk drivability yes I think a factory ecu tuned ecu will outdo a after market one, but this more a function of time invested in tuning. Aftermarket ecus have come a long way, now you have some of the features of a factory ecu or even more. For example I am kind of leaning towars ProEFI it has alot of ability to save a turbo boosted car from blowing up, like boost control cut (factory feature on OEMS), baramoter feedback and adjustment (good for elevation changes), EGT or Cylinder temp sensor feedback, fuel pressure, knock sensor (you can even replace what type of knock sensor) using all the senors you can now start doing fault condition reactions like 1. reduce rev limitor, reduce boost, add fuel, throw up check engine light. So how is MAP better than MAF alone I don't think it is. But then again how good is a Hotwire MAF versus a Karmex Vortex? The sensor is only one component of all available for tuning a motor. So I think with a good ecu that uses all the sensors it can at is disposal to protect the car from the typical failures of a bad fuel pump, too much timing, bad AFR, bad gas, high intake temps, and etc is the winning solution. Also you are right on a MAP sensors there is a correlation to volumemetric efficiency versus RPM and boost pressure. And every engine can vary somewhat even stock. Alot of systems now use both a MAF and a MAP the toyota Supra is an example one. So anyways in summary I would switch to MAP because most aftermarket ecus rely on a simply map of RPM/Booost/injectordutycycle simple tuning. Also I think that most after ecus have decent low speed drivability but once you get into open loop it is where they begin to fail, but now things are changing.. Now you can have full closed loop at 100% throttle and redline. Lets face it the 300ZX oem ecu is not bad just a little antiquated.
|
