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MarkM66
04-04-2006, 10:17 AM
Anyone use one of these systems.

http://www.massflowefi.com/

They make some lofty claims. Price looks pretty good for all that you get.

camcojb
04-04-2006, 10:50 AM
Anyone use one of these systems.

http://www.massflowefi.com/

They make some lofty claims. Price looks pretty good for all that you get.

Been debated on many boards. The company owner was in the thread on Chevytalk and then quit responding when the questions began to fly.

My opinion after tuning maf systems is it will work, but the "no tuning" part is not true. To get it to run it's best it has to be tuned. He can give you a base tune to run and many would think it was fine. But there's no way he can provide the perfect tune when he isn't tuning the system on your car.

The other thing is if you decide to change cams, injectors, etc. you have to send the box in to him for changes. You aren't able to do any tuning changes yourself. I would never buy a system that does not allow the end-user to do any tweaking to it.

Jody

Blown353
04-04-2006, 06:49 PM
From all appearances it looks to be a Ford EEC-IV coupled with a translator box to allow the GM MAF to work with the EEC-IV (I believe the GM MAF gives a frequency output and the EEC-IV is looking for a scaled voltage input-- that's what the translator box is for.)

No matter what they say it will need tuning. Things like A/E enrichment, startup parameters, VE parameters (fuel needed per unit of air flowing through the MAF in this case), timing curves, etc, all differ by application and there isn't one base map that will cover everything.

A MAF system does have the advantage of being more accurate than a speed density system because it measures actual airflow entering the engine (rather than taking a pressure reading and "guessing" the air entering the engine via temp/densitiy calculations) but it still needs to be tuned for the individual application. That's why 99% (maybe all) new EFI cars rolling off the assembly line are MAF-based-- they're more accurate than speed density, allowing for more precise fuel metering allowing better control of emissions and economy. However many of these MAF systems also use a MAP sensor to double check the MAF (often two-- one to check atmospheric pressure and the other for manifold pressure) and in the event of MAF failure they can go into a "limp" mode using either straight open-loop tables (usually based off TPS/RPM) or work off the MAP in speed density.

All that being said, retrofitting a modern OEM MAF system is definately a worthy goal, since OEM ECU's are usually leaps and bounds ahead of aftermarket offerings simply because they have to be to meet emissions, driveability, and economy standards... just don't expect it to be "plug and play" and they are often quite complex since the factory didn't design them intending your typical "weekend warrior" to be doing the tuning. In fact, many new ECU's are moving or already have moved to equation-based setups rather than table based setups (running strictly off equations allows much finer control since the ECU is no longer limited by taking the sensor readings and looking up a value in a table which only offers X number of cells of resolution, but can rather it can take the exact input parameters from the sensors and then plug them into an equation) so you better be good with math. :)