btleier

Hey guys I'm new to the RX-7 scene, however not new to cars, or turbos. My question for you guys is, why does it seem that the Power FC is the tuning platform of choice for the RX-7? From what I understand, the AEM can be hand for just a couple hundred dollars more. I was just wondering why you guys seem to like it so much, so I can better make a decision.

cewrx7r1

iTrader: (2)

Controls many stock functions plus more with a DATALOGIT, and is very user friendly.

btleier

I understand that, but why not just go with AEM, it controls all the same things.... and then some.... just because it's easier to use or what?

Guru03

Easier to use isn't even close. FAR easier to use and much more user friendly and allows you to see all the real time sensor data at a glance anytime. With the Datalogit it is far more than anyone will ever need.

btleier

does the power fc allow you to adjust timing?

btleier

anyone?

iluvmy3rdgen

yes.

cewrx7r1

iTrader: (2)

I suggest you go the the attached address and download and read the PFC manual. This thread was posted last week.

http://spipowerexcel.com/pdfs/fc_commander_fd3s.pdf


Then go read the STICKY pre-tuning thread on the top of the forum list.
SEARCHES will reveal a lot of additional info.

TailHappy

Biggest selling point of hte PFC for me was that I could plug it in and drive away. If you haven't modded your car much, the maps are sufficient to make your car run better than it did with the stock ECU (no 3000rpm stumble). Then with the datalogit you can still do 90% of the same things the AEM will do, so it will continue to support you as you build your car. Plus I liked the commander for monitoring things and making small changes. At the time, the AEM didn't have an equivalent, though that's probably changed by now.

From what I had read a while back, the AEM takes a lot more tuning on the front end to get things running properly. Personally, I didn't want to deal with that. The PFC is tried and proven and there's a wealth of information out there on how to deal with any issue you might encounter. From my brief time spent in the AEM EMS forums, it looked like a lot of less experienced people giving advice and there was very little specific to a FD......

particleeffect

i've always thought that the fuel control of the PFC was one hell of a convoluted mess. especially the whole base map+correction map thing. i mean, 2 different, related maps for one fuel curve?! granted i've never tuned my AFs before, but every time i look at the base map + correction map i'm in awe that they did it like that. user friendly? maybe. intuitive? far from it.

why couldn't they have just done each cell by injector duty cycle instead of asinine calculations?!

and the manual that comes with it? no. there is no manual. the PFC was not meant to be end user tunable. there isn't even a manual for the 3rd party datalogit, just a shitty yahoo newsgroup. which means every 5 minutes you have to feel like an idiot and ask another retarded question THAT SHOULD HAVE JUST COME IN A DAMN MANUAL.

/vent.

eViLRotor

iTrader: (2)

On a side note, how many other EMS aside from the PFC allow you too keep the twins in sequential operation?

TailHappy

Actually the base and correction maps make sense, once you realize what they're all about. I personally wouldn't want it any other way, now that I know how to use them. Originally, the base map was the theoretical amount of fuel that a rotary would need, and the correction map applied the necessary real world corrections to that. The brilliance of it for tuning is that the base map contains the injector times. The correction map is a percentage correction to that. So using the datalogit, you can recalculate your base map, which converts your correction map back to 1.00's, and then you can begin tuning the correction map and see exactly what changes you've done, working only in percentages. Makes tuning very easy.

Injector duty cycle would have been a nightmare since duty cycle is directly related to RPM. Inject the same amount of fuel and change the RPM and your duty cycle increases since there's less time for the injectors to fire. Using the correction map it's easy to quckly convert a AFR difference into a fuel percentage difference.

But I will give you that it takes time to learn the whole system. Not everything is intuitive, but if you're willing to trudge through forums you can find all the answers you need. The datalogit yahoo group is frustrating for looking up old posts, though, that's for sure.

cewrx7r1

iTrader: (2)

I agee with TailHappy about the base and correction maps, especially the DATALOGIT recalc funtion. Then there are the PIM maps for quick test fuel changes.

So much diversity for tuning. Then at the end apply it all to the FCM, and recalc it to the BM.

twokrx7

iTrader: (1)

Recall the PFC guys cracked the Mazda ecu and replicated it's functions, that's why they did the fuel with base and inj maps. Gotta do your homework before you critque.

I agree that with the Datalogit the INJ maps are wonderful for tuning. Once you recalc the base map and have all 1's in the INJ map it is so easy to tune cell by cell.

particleeffect

no, i was critquing on how intutive the system was. home work would negate the idea of intuition.

but i've been using the base 5.8 map @10-11psi for 9 months, it's run fine. i did have the problems with the AC in pos 3, but that has been shown to be a switch problem as the switches in the FD tend to corrode at the connections. and then my AC died, making that issue not as important.

it certainly works as plug and play. but IIRC it still doesn't run the EGR and something else for emmisions, since they don't have those in japan.

twokrx7

iTrader: (1)

Don't worry about the egr, the rotary motor doesn't need it for emmisions. My 94 egr valve gasket actually blocked the passages in the manifold ... straight from mazda.