I have the choice of getting either of these at the same price (used). In your opinion, which one of the 2 are more reliable, and has a more consistant power curve, (smoothness when the power hits)?

Thanks

 

Forgot to mention my mods: DP, MP, CB, Intake.

 

Neither, save up and get a PowerFC, instead of something that will be a hassle if you ever do more.

 

Well the PowerFC is out of reach for me. I'm getting married this year and plan on buying a house soon after. My FD will stay with these mods for a good amount of time. I do have plans on modding more, but it's not going to be for a pretty long time. I'm trying to achieve the most of what I have to work with.

 

Do you have a BOOST GAUGE? My guess is you're all over the place with a full exhaust and a boost controller should be your next mod.

 

M2 hands down. The PFS unit is better used as a paper weight.

 

I sure do

 

Why do you say that? (not meant to sound defensive, just want to know the reason)

 

Your boost doesn't creep or spike with the midpipe?

 

I've heard good and bad things about the EFI/PFS ECU's. I've also seen some people on this forum make good power with them so they can't be a complete waste of money. However, support for them may be the biggest issue.

You might PM a member by the name of "zullo". He is local to me and has one. He's in the process or trying to do something with it and may be able to give you his impression on the unit.

IMO, I would wait and pick up a used Pettit ECU. M2 does not recommend running a midpipe with their ECU (but people have done it).

 

Thanks, Mahjik! This is the kind of advise I was looking for! Always come through!

 

Well just do a search on the forum. Many owners have issues with them such as fuel cut at higher RPM. Basically the system seems to fight the stock computer. They don'y call it the Purple Peter Motor Eater for nothing.

 

I second the option of a used Petit Unit.

Check Petits website.

If you know your fixed mod list, and it won't change, you can just send your ECU to them, and they will update it.

If I had to have a reprogrammed ECU, I would want Petit. None of the others.

1st) The support will be great, and for M2 ordering products, much less getting support, everything blows. Plus they are in questionable condition to say the least.

2nd) There are a number of detractors for PFS.

3rd) A blown engine on a misprogrammed ECU will cost you a lot more than a PowerFC. So if I was going to take that risk, I'd get a Pettit.

 

PFS

You get the same as an M2 (being able to tune it for 14.5 lbs) and much more.
You have a readout of injector duty cycle, rpm, injector pulse width, O2, boost/vac, data logging capability plus boost controler (for use with a highflow cat), ignition retard/advance. And you have 3 different fuel & ignition maps for 3 different boost settings that you select by keypad or a dial.
So, with the M2 you won't ever be optimal because you will never be able to tune it. With the PFS you can dyno tune the car, which is optimal, with every new mod or lack thereof.

Raj

 

Thanks for all your input fellaz! I think I'm going to search for a Pettit ECU.

 

I cannot speak for the PFS PMS, but I have the M2 stage 3 ECU. If you have a midpipe, then FORGET about the M2 ECU. It cannot compensate quickly enough for the boost spikes associated with running a midpipe. BELIEVE ME!
You say you do not have enough money for the Power FC, given your current mods with or without an M2 ECU, you are looking at about $6k all said and done, to replace the motor you are about to blow up.

Your best bet is to get either ECU, dump the midpipe and get a high flow cat. I'm partial to the M2, but will get the Power FC in the future.

 

MP=Engine Death?

 

I have the M2 stage III with all my mods and it runs well with a nice 12 psi boost. It is true, there is no support for M2. But I was looking for a bolt on mod without a lot of custom tuning.

 

Nah. Get your wastegate ported and you should be fine. Or put a small restrictor plate in there to be on the safe side.

 

Like me

 

Six of us ran the PFS Purple for years. All the bolt ons and ported motors 15 psi of boost. Never blew an engine. It's adjustable and program maps are readily available. The pettit/M2 units are limited to their pre programed chips. We found them to generally suck.

 

I also ran a PFS PMC for a while with ported engine and no problems. I had a m2 way back when. It sucks because once you decide to throw on a mid pipe its no longer any good to you since it will run the car lean. I have no idea about the pettit but given the choice of being able to adjust your maps and not being able to adjust I would rather have the ability to make some changes if needed.
Purple box gets my vote. I have one to sell to if anyone is interested. /

 

Sooner or later you are going to have a boost spike at transition. If you are not running the right ecu, you will ping. And I hope you know that all it takes is one ping to shoot your apex seal out your exhaust. Be safe.


Sounds like people here have had good luck using the PFS and Pettit. I have no experience with them. Sure you could port your wastegate. but by the time you buy an M2 ecu and have pay the labor for having someone pull your turbos off and port the wastegate, you could have bought a brand new Power FC.

 

You still need to port your wastegate with PFC if you want run midpipe. So ?

 

I have the PFS box

Advantages
1) tunable - you can make a lot of power
if you know what you're doing
2) adjustable boost control
(something you need with your mods)
3) monitoring - can provide real-time
timing, fuel, boost, and error code
feedback.

Disadvantages
1) tunable - you could easily blow things up
if you don't know what you're doing
2) no support - If you can get
PFS to answer the phone (unlikely),
they will just tell you they don't have
time for RX-7s. And finding anyone who
has ever tuned one is difficult.
3) quirks of oem ecu - being a piggy-back,
the idiosyncracies of the stock ecu still
shine through.