The PFC is frequently recommended as a basic upgrade on cars even close to stock, some calling for the swap in the name of reliability. With hardware that includes a faster processor and software that includes a wide range of adjustability and an increased number of map cells, most agree the PFC is the superior product when compared to the stock ECU.

The issue I have a hard time getting past is that most PFC benefits seem to hinge on comprehensive understanding of a) general tuning, b) PFC functionality and how to fully utilize the software, and c) stock ECU functionality and mapping for use as baseline values. Trying to find someone with the combination of the three seems easier said than done. hwnd was trying to dissect stock ECU mapping at one point but I'm not sure if he ever finished, so there may be very few people that understand the original Mazda maps.

The PFC surely has the ability to function at a higher level than the stock ECU, but with all that can go wrong with a bad tune and the difficulty in identifying those who really understand tuning with the PFC, it seems like the a modified stock ECU is the safer way to go?

 

You've outlined a lot of very valid concerns about swapping out a stock ECU for a programmable standalone, whether it's a PFC or something else. What is your particular situation with your car?

The problem with the "modified stock ECU" is that the options are very limited for the FD, and nobody is quite sure exactly what these reprogrammed ECUs changed. On an FC with Rtek 2.1 modified stock ECU you can change the mapping yourself, but with an FD you are stuck with a black box.

 

yeah most of these "chipped" modified ecus are only setup for a very specific set of mods, if anything is different then the tune will be off and it could be risky to run it

for example if your motor Is ported, it would be very hard to find a chiped ecu that matches it, as everyone makes different size ports or doesn't know what they did in your engine....

even two cars with the same mods may have different fuel needs, which is why a fully adjustable ecu like the pcf is a good idea. it can be tuned specifically to match your car.

what kind of mods do you have and is there a modified ecu that matches what you have exactly?

 

The FD is bone stock. Will install a down pipe to get heat out of the engine bay and likely add an RB cat back for the sound; manual boost controllers to keep boost at stock levels. No other power adders planned, as I'd like to keep the car very close to original. The car would likely be fine with the stock ECU given the minimal modifications and stock boost levels but I don't want to be anywhere near the edge of running lean and would prefer to add a little fuel to compensate for the better air flow.

arg - Black box indeed. I've read the M2/Pettit/Knightsports ECUs turned up the fuel as much as possible but don't know if that's actually the case. Do you know if M2 or Pettit ever disclosed an official change list or who performed the modifications on their behalf?

komp - Trying to match a modified ECU to a given set of modifications is definitely a limitation. I think hwnd was hoping to address this issue with stock ECUs that could be easily reflashed but it doesn't look like he finished.

 

My car drove excellent with the Pettit. I'll have mine for sale soon Best i can figure is there is no real reason other than to turn the fans on sooner to upgrade to a PFC until you're out of fuel with the stock injectors power wise or not stock port or want to delete emissions.

My car will be tuned now on the PFC with the new turbos/injectors/etc for this year though.

Jason