Alright guys I am now well into tuning my safe, low boost tune on my series 4 Turbo II using an FD power FC with the Banzai Racing adapter kit. I have spent a lot of time debugging stuff and learning so hopefully I can impart some knowledge to anyone else taking on this kind of project.

Installation

http://www.banzai-racing.com/product...ss_adapter.htm

That's the writeup, just follow the instructions to get everything plugged in at least. You need to make sure you get the circuit opening relay wire hooked up (hook it to the dash harness side of the brown wire, just like the writeup says) or the car won't start. Vehicle speed and knock sensor wiring is optional, but a knock sensor connection I would definately recommend. Be careful with the trailing coil wiring so that you will get proper spark when you start the car up.

The other thing at issue here is the TPS (if you are s4 like me). There is a wire on the adapter harness to hook to an s5 or FD full range TPS. IMO it's not necessary at all. The most important use of the full range TPS is controlling the electric OMP, which s4 cars don't have anyway. You will not have throttle tip-in problems/hesitation in my experience. I richened up the "accelerate injector" and "Accel vs TPS1" settings to help with this. See Chuck Westbrook's notes about how all this works.

If you decide to keep the s4 TPS, you need to splice the "FRT" unterminated wire to the narrow-range TPS wire. This is FC pin 2I (see FC FSM page 4B-32) or FD pin 3F (see FD FSM page F-158). Get your Commander out and go to etc --> sensor check. VTA1 and VTA2 should have the same voltage. Turn the TPS adjuster screw until they are around 1 volt with the throttle closed.

You really need a datalogit if you actually plan on doing any tuning yourself. It's even more important on an FC application because there's a greater chance that you will have to play with the supplied Banzai Racing basemap to get your car to run decently. For information on how to set up an LC-1 wideband with the datalogit, see my other thread: https://www.rx7club.com/power-fc-forum-47/my-power-fc-lc-1-xd-16-datalogit-wiring-diagram-707298/

If you are running an electric fan the Power FC can activate that for you, which is mentioned in the Banzai Racing writeup.

Preparing to start the Car

If you have an FC and you are going with a standalone like the Power FC, you are probably in the process of doing other significant modifications like I was. I went for the Power FC because I was putting together a T04S setup with 720/1680 injectors. While a common enough setup on FD's, in the realm of FC's, this is pretty heavily modded. So you need to make sure that everything in your car is sound before you try and run the Power FC.

1. Fix your fluid leaks. This seems like a no-brainer, but take it from me--don't have any ghetto stuff on your car. Do all your turbo oil lines in stainless steel (if you don't have a hybrid turbo) for example. Make sure you jumper the fuel pump check connector on the passenger side shock tower to check for fuel leaks. Check your pulsation dampener. Speaking of fuel, you should probably set your external FPR to 40psi base pressure (without a vacuum on it) if you have one, as that is what Banzai Racing recommends.

2. FIX YOUR VACUUM/BOOST LEAKS. This gave me a lot of trouble and I cannot stress this enough. I was doing a ton of work on the car and had developed a number of little leaks from bad gaskets, vacuum routing mistakes, etc. Vacuum leaks will give you an inaccurate MAP reading and may make your car idle high or not even run at all (as I encountered).

I use a boost leaker tester to pressurize the intake (along with some soapy water), like the one available here http://www.boostpro.net/prodtester.html . You will need a reducer coupler to make it work. If you still have a top mount intercooler, you can build a crossover pipe from the plumbing section at the hardware store if you want to test without that big intercooler in the way. You really don't need to run much boost through the system to hear/feel the air leaks, just a couple psi really. I noticed I had a number of leaks from blockoff plates (ACV loves to leak) and poorly fitting vacuum hoses. A lot of hoses seem like they would work with 3/16" hose but in fact will boost leak unless you have 5/32" hose on them. This is even with a ziptie.

3. Make sure all your sensors are in spec. You will already be replacing the MAP and IAT sensors. Check your thermosensor and TPS. The TPS diagnostic procedure is well documented--check to make sure there is a consistent sweep of resistance. When you set the voltage to ~1, push the pedal down and see what voltage it hits at WOT on your Commander (VTA1 and VTA2 on sensor check). It should be like 4.9ish I believe on a perfect sensor. My original sensor only went up to 3.8 volts, so I bought a new one from Ray Crowe at Malloy Mazda (it was about $185 shipped at the time).

Checking the thermosensor requires comparing it to an aftermarket temp gauge. Over time these sensors develop higher resistance. My thermosensor was literally about 50 degrees Celcius too cold of a reading in comparison to my aftermarket gauge. This can result in the computer remaining in cold start mode which will affect your fuel and ignition timing. You can get an OEM replacement for about $40ish? or you can go to an auto parts store and get one for about $15. I went OEM.

Starting the Car

Connect the Datalogit and save a copy of whatever tune was in the PFC when you bought it. Obviously if it's brand new it's going to be the base map, but if it's used it may have some changes. It's useful to keep these saved files for reference. If you don't have a brand new PFC, reinitialize your Power FC using the datalogit or the Commander (Etc--> Initialize), and remember to turn the key off and then turn it back on. This resets the idle learning procedure which is in the instructions available on the Apexi web site.

Load your map in there, turn the key, and hopefully it will fire right up. Then you can check for spark at the trailing coils as the Banzai Racing writeup recommends.

OR you will end up like me and have a bunch of trouble getting the car to idle. Long story short, for some reason my car requires more fuel than the basemap that Banzai Racing supplied. I suspect it is because I have a large streetport. The Banzai Racing basemap that I received is a leaner tune than the FD basemap built into the computer. I ended up copying over the richer INJ Map and Base Map tabs from the built-in Apex'i tune, which I had already saved on my laptop. I replaced the INJ and base map supplied by Banzai Racing with the richer Apex'i tune and now the car idled. I figured all this out by datalogging my startup attempts and utilizing the wideband input to figure out why the heck my car was dying out on me.

At this point your car should be running and idling, perhaps well or perhaps poorly. You can now attempt to get the vehicle to the tuner or tune it the rest of the way yourself, which is beyond the scope of this writeup of course. Just remember that in my experience the Banzai Racing map is leaner than the basemap for the FD, and the FD map is good for maybe 300whp (I actually compared the two maps in Excel). So obviously take your time and don't even pull the car out of the garage until you're sure it will idle decently and not leak anything.

 

Nice write up.

With the larger cc injector combinations our base maps will need more correcting on the installers part. This is due to the wide variations in manufacturers of injectors and flow rates. I have spoken with both RC and Gordon at Witchhunter and they both tell me that the 1600cc injectors will flow test at anywhere from 1400-1800cc's. The same holds true for 680, 720, 750, 820, 850 there is always a variation in the flow rates between Denso, Bosch, Rochester etc.

We can only supply a map based off the parameters that are supplied to us, in most cases the cars fire right up, on others there is some tuning to do. This is the case with any aftermarket ECU installation.

Another thing that should be added to your tuning notes is the map sensor vacuum signal location. This needs to be a good vaccum and boost source. If it is a shared source then make sure the the other component does not leak, such as the BOV. If it is hooked up to the wrong nipple on the UIM it is possible it will not see vacuum or boost. This is critical for the PFC to know where it should be in the map.

 

FYI my injectors were 720cc Greddy/Denso and 1680cc Bosch units. These are all topfeed of course because it is an FC. The Bosch 1680's need an s5 pintle cap (keep the stock injector grommet) in place of the Bosch factory o-ring and spacer or they will cause a vacuum leak. s5 pintle caps are available from Mazdatrix for $2 each or so.

Based on some searches on the 2nd gen forum, I hooked up my MAP sensor to the bottom nipple on the front of the UIM. There is also a vacuum source on the bottom nipple of the back of the UIM. On the back of the UIM those other two nipples are sources of fresh air for your air bleed sockets. I'm not sure about the other two on the front.

I had the GM MAP sensor. I took a 3/16" hose and clamped it to that bottom nipple on the front (using a small hose clamp). If you do not clamp it, it WILL leak. My pressure tests confirmed this. It will then fit very snugly on to the nipple on the MAP sensor. My pressure tests reveal that zipties are semi worthless for preventing boost leaks. A ziptie may reduce the chances of the hose blowing off, but it's more important that you have the smallest hose you can fit on the nipple. The reason why I had to clamp the hose on the UIM was because the nipple is not barbed liked the nipple on the MAP sensor itself.

Other options for your MAP sensor source include drilling and tapping your ACV blockoff plate.

 

Great info I've pretty much decided that I will be using a Power FC when I get to that point. This will definitely come in handy.