Originally Posted by BoZ05

The Map Ecu 2 from PHR looks more promising than the Map Ecu. Still a piggyback that alters the AFM signal much like what the VPC did. Therefore altering the fuel maps, essentially alters the AFM signal going to the stock ECU thereby causing massive amounts of changes to the timing curve. If you don't understand how, then read my posts in mr2.com, mr2oc.com and emspowered.com on how an SAFC directly affects the timing output from a stock ECU. My board name is Sang over there.

Some are going to argue that the Map ECU is not the same as an SAFC, while true, the principles are still the same...you're manipulating the AFM signal to force the stock ECU to do what you want.

Now, the benefit from the specs I read about the Map2 is that this one can control timing as well. Now, it sounds like a benefit, but keep in mind...you'll be walking a very fine line with tuning the timing. No one has yet, been able to exactly determine how much timing advance you'll get from the stock ECU when it see's significantly less load. Aaron at ATS has at one point, but only to a few %'s, nothing like the extreme cases you'll run into. So make sure you have a damn good tuner if you go this route.

Now I say this in regards to your setup in particular, because i've read your threads on mr2oc, and gave you some recommendations on your fuel setup. The power you are looking for is going to need in excess of 800cc/mins and larger injectors. That is almost TWICE the size of the stock injectors. Now, think about how much fuel you are going to have to tell the stock ECU to pull away during part throttle, low load situations. Now think about what I said above and removing fuel, essentially screwing with one of the axis of the AFM's signal. Thus the ECU predicts less load based on those altered values, ergo you get timing advance.

Long story short...dreams of lots of power, and piggybacks are a no-no with the mr2's ecu. I'd go with MS over any piggyback...

As I said before, WOT tuning is the easy part. You wont have to mess with the timing curve much, but you'll be depending on boost pressure to lean out your AFR's. Leaners AFR's, less fuel you'll have to remove, less timing advance you get.

My $.02

-Sang