rx7dave77

Does anyone out there know the differences between the two??? Just wanted to hear some comments/recomendations...

XSeLR8nRX7

i have a petitt ecu w/ a 1bar chip in it...runs pretty well but on the rich side at 13lbs of boost. I haven't ran it much more than that.
The M2 is known to be a bit more conservative and not recommended to be used with a midpipe although many use it with a mp with no problems...
There both very good ecu's and should change the cars performance dramatically.

-ken

rynberg

The M2 is tuned for our crappy 91 octane gas in California. Therefore, the timing might me more conservative than with the Pettit ecu. The Pettit ecu seems to be more upgradeable as well.....

rx7dave77

Okay, my friend Adam knows his car pretty well (as opposed to me!) and he has the M2 ECU. I was curious as to how they tune this thing and how "fluid" is it? I saw that the Pettit ECU has the ability to upgrade, and I was wondering how and who/what determines when it is time for an upgrade? Does that make any sense? What I mean is, right now if I only have a cat back and air intake, and then get a performance ECU, how many "upgrades" would it be good for? How does it know what I have upgraded and how does it compensate? Okay, I feel pretty ignorant on this, so please learn me some! HA!HA! Adam, you around???

rynberg

Pettit and M2 add daughter-boards to the main ecu circuit board to change the timing and fuel maps. The changes are done based on a standardized mod list (for example, M2 has three "stages"). The architecture that Pettit uses allows you to change the daughterboards when you do upgrades.

The chips are not smart and don't make changes you change your mods. Computers are dumb man, after all, they can only count to 1....

rx7dave77

So, how would you know when you were at the threshold of needing another upgrade? Also, what would happen if one of these ECUs were placed in a stock car - no mods???

Wargasm

I haven't checked prices on parts recently... but why not just get a PowerFC? WAAAY better.

Brian

es

With just an intake & catback I'd say wait & get a power fc.

rx7dave77

I don't know anything about a PowerFC. Isn't that a whole lot more "involved" than the two ECUs I'm talking about? I am not looking at making any wild and extreme upgrades to the car...I can't afford it! I do, however, want to mess around with it a little bit more, and want to keep everything safe. I have basically no knowledge about the specifics of what these things do, so if I had something where I had to make decisions (instead of a programmed computer), that could get very scary and very ugly!!!

Juster

I have the pettit unlimited ecu. I've been told from pettit that i can run single so long as i upgrade injectors and fuel pump. im currently running all the bolt ons and so for its kicking ***@@!!

Don-94BB R2(NJ)

I have the standard pettit chip...i think its called the 14.7 chip or something like that. When i called about it the guy on the phone(sounded real old....think his name was jeff)..he told me it was good for intake, IC, and full exhaust. I have all that except for still having the stock main cat in. It runs fine and hits 14-15lbs of boost with my J&S showing no knock readings.

Plan on doing the HF cat and BC(will lower boost a pound or two) and am wondering however if i will need the unlimited chip?

>>>Juster...hows your boost with all the mods? thanks.

artguy

both these ecus you mention are a waste of money....get the power fc....i went the cheap way with a gforce (same damn thing). the fuel curve and timing they do is just guesswork for your car. if you get the power fc you can datalog everything and make adjustments to get your car perfect....not to mention monitoring everything.

I sold my gforce for a loss...the pfc is a huge improvement.


j

RageRace

Im definetly going to agree with ARTGUY, those ecus are a big waste of money. You guys overrate those ecus way too much. Those ecus are really nothing more than a stock ecu with the fuel defense overridden. All it does is let you bypass the stock ecus boost setting and run more boost. So now you can run more boost than your system can support(THAT IS NOT A GOOD THING). Why do you guys think that just plugging in a PFC will give you close to 30 hp (SR Motorsports), it is because the PFC actually corrects and enhances your maps. those ecus dont. I was talked into a Pettit unlimited at first too, so i have experience w/ them, and i am so glad i got the PFC( it is night and day difference). Save your cash and spend a little more $ buying a PFC, Haltech, etc. You will be much happier.
To the other guys thinking that those ECUs are capable of controlling bigger injectors ( you are very wrong, if you do that i can almost guarentee u will blow your **** up or it just wont run)
Also it doesnt matter what kind of upgrades you have, if you are not running a standalone and are boosting 14-15 psi you will eventually blow your **** up too(i did). There are hundreds of threads on this same kind of thing all over the forum. Take some time and research it. It will definetly pay off.
You guys need to stop telling people to do stuff that you dont know about. If Pettit told you that u can use thier ecu to control a single and bigger injectors and u believe that your an idiot(ask yourself how will you control duty cycle, timing, fuel, etc. YOU CANT!!!!) You guys are only helping screw each other. Call a REPUTABLE shop or talk to REPUTABLE people, you guys seem to have no idea what you are talking about and should do some more research before someone listens to you and loses alot of money.
My .02 cents take it or leave it.

rynberg

Go away bitter boy. You have already been proven wrong the last time you started spouting off. Hell, even the owner of ASI Racing came on here to disassociate their company from yourself.

The Pettit and M2 ecu's have daughterboards which change the fuel and ignition timing maps to handle more boost. They are not just fuel-cut defensers. People running PROPER mods for these chips have not been blowing up motors. You had a bad experience with Pettit. So what. In the end, your motor blew because YOU made a mistake.

I would be willing to bet that more people have blown motors tuning the PFC than with the M2 and Pettit chips. The PFC doesn't "correct and enhance" your maps as you put it. It comes with base maps that need to be tuned for your application. The success of that depends on the skill of the tuner.

All that said, I believe the PFC is the better route to go but for some people, the plug-in ecu's do everything they want them to do.

fatboy7

I don't own an FD, but it seams that 1.5k+ for a full EMS is a bit much, if all you plan on doing is up the boost a bit, and simple mods like intake and exhaust. I do know that the speed density type system requires that something changes fuel wise, so I don't see why either of these two 'chips' wouldn't at least help. Of course I don't think I'd ever upgrade the turbos while running such an inflexible ecu. Big HP calls for a fully flexible system.

rynberg

Of course, no one said you could run major modifications on the Pettit or M2 ecus. They work great for what they were meant for -- 12 psi with intake, downpipe, exhaust, and intercooler. Anything else -- not so good.

BTW, the FD does not use a speed density (mass flow) system, it uses a pressure sensor to determine the amount of fuel to provide.

Also, a PFC w/commander is $1250 at the rx7store.net or $1330 at Rotary Performance (who is an authorized Apexi Excel dealer). FD mods cost money. They aren't Mustangs....

rx7dave77

Well, I went with the Pettit ECU and installed with Adam C's help and watchful eye. It's running great and I am around 12.5 psi. I don't plan on getting "crazy" with this car. I'd like to keep it emmisions legal and don't think I will do much more than a downpipe and intercooler. So, I think this should work for me. Thanks for the input from everyone!

RageRace

First of all RYNBERG you are incorrect on a couple of points. Next why dont you learn to read, and comprehend information that is given to you. I dont know anout the M2 ecus but i know for a fact that the Pettit ecus are not modified except for bypassing the fuel cut. By the way where is your proof of the "change in the ignition and timing maps" have you ever data logged this information that you so willingly want to share with everyone?
Also with the PFC, maybe you have never seen a dyno graph before, but if you look at the tests that have been done on the dyno with a car with a PFC you will notice a much smoother curve than without one(or any SAMS). Just a Q for you since you seem to know all the facts, why by simply plugging in the PFC if it doesnt correct maps and timing do you gain hp even on its base maps?
Yet another point that i would like to make is that this guy is talking about running 15 psi on one of those ecus, i tell him that is way too much and you want to argue with that, then say in your next post that 12 psi is all that its good for. You need to make up your mind and do some research yourself. O yea what kind of shop tells someone that he can run bigger injectors on a PETTIT ecu!!!!
I would like to add to your other comment that I never associated myself with the company of ASI racing, i just stated he was a good friend and great mechanic. I could throw up all the OWNED flags but instead ill let you come back with some sorry *** excuse and NO PROOF of anything that you are claiming. All this ownership from a 20 year old Firefighter/PARAMEDIC(sorry i mean "BOY") Get your facts straight and learn something in the process!

RageRace

Im sorry to Rx7Dave i got a little off your Q. The PFC doesnt require really anything more than plugging it in, thats whats so great about them, you can plug it in and get better performance and then when your ready go to a dyno with a GOOD tuner and get even more out of it. Ive seen them sell on here used for $800-1000. You are going to spend 800 on an unl. ecu and not even be able to tune it. Do a search in the parts for sale and try and find a used one for a good price. If you do get the Pettit or M2 limit it to 12, 13psi max( anything over that i would highly recommend using race gas: VP 103) it will keep you A LITTLE safer if you want to run more boost.

rynberg

Your lack of maturity is readily apparent but I'll respond anyway.

You provide the proof. Both companies add daughter-boards to the stock ecu that change the timing and fuel-maps. If you "know for a fact" that they don't, YOU provide the proof. Until then, I will continue to believe that they do change the maps and timing (and so will everyone else).

Also with the PFC, maybe you have never seen a dyno graph before, but if you look at the tests that have been done on the dyno with a car with a PFC you will notice a much smoother curve than without one(or any SAMS).[/QUOTE]

My dyno curve looks plenty smooth to me. Of course the PFC will give a smoother power curve, it is a 16-bit ecu compared to the stock 8-bit. I never said the PFC wasn't better than an M2 or Pettit in this regard.

Just a Q for you since you seem to know all the facts, why by simply plugging in the PFC if it doesnt correct maps and timing do you gain hp even on its base maps?[/QUOTE]

You gain more power because the base fuel map for the PFC is actually leaner than the stock ecu fuel map. If you don't believe me, you can view the wideband test results on Wade Langham's website.

Perhaps your poor use of the english language is preventing me from understanding what you mean "the PFC corrects maps and timing". Your statement implies that the PFC self-learns the maps for your car. This is not true.

Yet another point that i would like to make is that this guy is talking about running 15 psi on one of those ecus, i tell him that is way too much and you want to argue with that, then say in your next post that 12 psi is all that its good for. You need to make up your mind and do some research yourself. O yea what kind of shop tells someone that he can run bigger injectors on a PETTIT ecu!!!! [/QUOTE]

I never said that you could run 15 psi safely on a Pettit ecu, although many people have run 13-14 psi just fine for a long time. I am always researching, as only a fool thinks he knows everything. I'm not the one who blew a motor due to lack of research....

I would like to add to your other comment that I never associated myself with the company of ASI racing, i just stated he was a good friend and great mechanic. [/QUOTE]

I didn't say you did. I just stated that the owner of ASI Racing posted to make sure no one thought you were.....

I could throw up all the OWNED flags but instead ill let you come back with some sorry *** excuse and NO PROOF of anything that you are claiming. All this ownership from a 20 year old Firefighter/PARAMEDIC(sorry i mean "BOY") Get your facts straight and learn something in the process! [/QUOTE]

Yeah, I've been so OWNED, I'm leaving the forum. Please point out where I stated anything erroneous, teacher. Please, I need you to get my facts straight so I can learn more about the FD.


rx7dave77: I apologize for hijacking your thread. I'm glad you got an ecu you are happy with. Good luck!

RageRace

Again like i said the first time, YOU are the one trying to tell other people that the Pettit ecu has a daughter board, which is incorrect. My info. is coming from 2 different sources both of which worked at Pettit for years. Im sure you have all the facts and good sources for your information though (current Pettit employees) LOL. You happened to prove me right in all my points i was trying to make anyway: Take notes schools in session:
1.The PFC does ENHANCE(en-hans):to make greater. By smoothing out your curve you have just, lets all say it together now you "ENHANCED" your cpu system.
2. CORRECT(c-o-r-r-e-c-t) v. - To make right. When using the PFC with the specified mods on the base maps
you not only get a smoother "ENHANCED",refer to #1, graph but also gain power while staying at a safe AFR. I believe that yes, yes it did, it "CORRECTED" your stock map.
3."Hell, even the owner of ASI Racing came on here to disassociate their company from yourself"-RYNBERG."Why this car left Pettit in this condition we will never Know,But it did happen.And Ill vouch for that.And with this said I feel you as a consumer should thank RageRACE for sharing his experience and continue on making your own choice as to where you should do business." ASI's exact stament, you have no right to make your interpretation of this comment a negative one and put it up on this board anyway(post in the right section and try not to give misleading information)
4. Im glad you at least didnt have anything to say on the "I have the pettit unlimited ecu. I've been told from pettit that i can run single so long as i upgrade injectors and fuel pump."-JUSTER. A response on that comment to you would be suicide.
5. TEACHER(teach' er) n.- 1. To communicate knowledge or skill. 2. To provide instruction in. 3. To give insight by example or experience.
Ill right my name on the blackboard for you
MR. RAGERACE LOL LOL LOL (Can I throw up the flags now...... no...no that was too fun.) Defend yourself again bro your making yourself look bad. Now go right on the blackboard 100 times "I was OWNED"