Thoughts on Mass Flo EFi system?
 

http://www.mass-floefi.com/

Looks like an interesting system with a little more flexibility than the FAST EZ-efi for higher hp applications.

Anyone familiar with the system?

What's your application? Cam specs?

BBC....crane cam....moderate lope.

I needed a little more than that on the cam but imo it won't like it. I've replaced a few of those, the last one was a 427W Ford with a 246/249 @ .050 Hyd roller, ran like **** with the MassFlo. Sent the ECM back 3 times for 'recalibration", never worked right. Put an Accel Thruster on it instead.

Sorry...it been 20 years since the cam went in and the card is long gone. I would say it's on par with mid range factory chevy cam....hydraulic...nothing too radical. Was it a vacuum issue? They seem to say that low vacuum is not an issue at all like with some of the other EFI set ups.

Vacuum is a big part of it, but also you only have a 20degree window for timing adjustments as well. Plus there's no cold start advance and it lacks a whole bunch of other stuff too, or is only available at an additional price.

The better systems, Accel, FAST etc are easily adjustable for larger cams. Most OEM ECMs are the ones that don't like low idle vacuum, somehow that got carried over to describe the aftermarket stuff too. In most cases that's not true.
Let me know if I can help, I did Accels' How to DVD so I'd have to say I'm pretty qualified. I have plenty of references as well.

Thanks
Mark