Chose the ECU for me?
 

Which of these ecus will squeeze the most power out of these mods at 12 psi and be safest?

Intake
Down Pipe
Cat-Back
HKS Grounding Kit

Possibility of a aftermarket SMIC later and other minor boltons.

just save the money and get a PFC :).

The Pettit ECU will be the more aggressive out of the bunch.

Hey the Power FC isn't on the list? That's the one you need LOL :)

Greg Blair, a buddy of mine from Cincy, has an M2 ECU on his lightly modded FD (<30K-mileage original motor, stock twins, dp/hi-flow/cb). His car made 300 rwhp on the first run, but got lower readings after that (due to heatsoak from the SMIC). Anyhow, his AFRs were very good, 10.9 to 11.1 @ WOT 7000 rpm. Pretty much stock AFRs. This testing was done @ Rx7 Store, so Jason Baughman and Zavier Neeley can attest to the M2 ECU's performance that day. Not sure how different or similar the Pettit unlimited ECU will be though?

Those are nice numbers, but I've yet to see anyone on a GForce or M2 ECU get anywhere near 350-360rwhp as the guys using the Pettit ECU's.

Oh I agree. If you're shooting to max out the rwhp with twins (be they US spec or Japan spec), Power FC is the only way to go IMHO :) I wasn't aware Pettit ECUs made that much juice!

I like the PFC, but I don't think it's for everyone. ;)

RTS3GEN here on the forum (you remember him from the Road Racer's thread), he's running a Pettit Race Port with the Pettit ECU at 357.2 rwhp 15psi and 11.77@116.77mph.

Not bad for rechipped ECU. :)

NO that's great! With a Power FC, KD Rotary street ported motor, I have 370.9 rwhp @ 7000 rpm, 16 psi from the J-spec twins (I was surprised the little twins could make 16 psi LOL :) ), so not that far away. AFRs for me are 10.9 to 11.1 @ WOT 7000 rpm. AIT and WT at the time was 35 C (95 F) and 85 C (185 F), so the GReddy 2-row FMIC and Koyo rad were doing their respective jobs, keeping air and water cool during the two-hour dyno-tuning session @ Rx7 Store :)

i know power fc is the best. thats my ultimate goal but not until I go single. I plan on staying on the twin for the next 2 years so I only need something to hold me over.

How are people running 15psi and 357hp with the stock fuel system? I though remapped ecus wont work with upgraded injectors and fuel rails. How are they not maxing the stock injectors duty cycle out?

High injector duty cycles are not necessarily a bad thing. Check this thread out for more information about it:

https://www.rx7club.com/showthread.p...hreadid=259912

I would go ahead and spring for the Power FC. It's a better system if you have access to a qualified Power FC tuner and reasonably-priced dyno time. I've read of a certain Ivan guy, that BATMAN knows whose twins and stock ported motor makes 390 rwhp with a Power FC. BTW, my 370.9 rwhp came only after I added the HKS Twin Power ignition amplifier. My stock ignition wasn't doing the job, and was missing @ high rpms, thus netting only 341 rwhp @ 6500 rpm. The 370.9 rwhp (with AFR @ 10.9-11.1), @7000 rpm, 16 psi boost reading showed my injector duty cycle at 84.7%...luckily I have no other power mods coming.

Get a PFC and skip the commander if you want to save a few bucks.

power fc should definately be a choice. you will end up saving money in the long run.

Feh, talking about how much power XYZ made on what ECU is silly guys. I made enough HP off of an original PFS Gold box on a stock block to pull 125mph in the 1/4 mile. Does that mean everyone should run out and try to buy an old PFS gold computer? Course not. The people suggesting a PFC have a valid point with respect to being able to adjust programming later. That particular issue should be given serious weight.

Kevin T. Wyum

Agreed. No sense in buying an ECU twice....I knew I was going to go single before I bought the car so every mod I did (besides my DP & Intake) was geared towards the single conversion....You will save money if you just get the PFC now. It doesn't hurt to run it with the twins :)

RxSeven1, i was in the same position as you are not too long ago. i was thinking about getting the Pettit ECU and holding off on the PFC. after reading around on the board and talking to a few 3rd gen owners in person, it seemed to me that the PFC is a MUCH better idea. i'm sure the remaps are excellent and all, but considdering how much more the PFC has to its capabilities, you save money on it. it has boost, AIT, WT, pretty sure there's a knock sensor as well as AF readings that it can give you. add up the cost of all these gauges (if you don't own them and had planned on installing them... as long as you don't still wanna do it as a redundancy) and you're saving money. plus, there's the overall adaptability. for most of us, the PFC will allow us to make ALL of the changes that we will ever do to the RX without having to get a new ECU. my honest opinion is that the PFC is the best way to go if only for its ease of reprogramming. if you want to save a little money up front though, hold off on the commander. (its a nifty little thing to have though because of all the info it can give you :))

Just keep in mind a few things:

a. While the PFC might "display" knock readings, it does absolutely nothing with them. It doesn't retard timing like a J&S System (or even a stock/rechipped ECU for that matter).

b. While the PFC can display all of those things, you still want gauges for most of them as you need something easy to monitor.

The PFC is not for everyone. Just make sure that if you plan to get one (or any programmable ECU), you are already making plans to have it professionally tuned (or tune it yourself) on the car. Don't run base maps or "tune by mail". If you not, you are just asking for trouble.

i wasn't sure about the knock sensor in it... but at least it can tell you where you're at. i didn't know that the stock ECUs had a knock retard in them though either (learn something new everyday).

That really doesn't do much good unless you are lookingn at it instead of the road (which you won't). By the time you notice bad knock readings, it would be too late which is why there are products like the J&S Knock Retarding systems.

Don't get me wrong, the PFC is a good unit. However, there are good reasons for using them, but monitoring isn't really a good one unless you are logging for reviewing it later. For information while driving, gauges are still the best option.

if i can mount the display fromt the commander into my steering column where say a boost gauge would go normally (which i plan on doing and do have the capabilities available to me) do you think that will suffice for the time being though? i wanna do the gauges, just have to prioritize my spending :)

Well, the display is not too big, which is why people still use gauges.

IMO, every FD should have a boost gauge and a water temp gauge (or at least linearize the stock one). After that it depends on your usage of the car. If you are going to be doing your own tuning, you should invest in a Wideband O2 with an A/F gauge.

Other gauges, like Oil Temp, may come in handy down the line depending on what activities you do (i.e. road racing or other stuff).

UPDATE: I ordered a used PFC last week.

sorry to steal your thread away RxSeven1... but thanks Mahjik.