ECU management: Stand alone vs. SCT Pro Racer

[FocusSportVP]

Let's discuss the pros and cons of both the SCT Pro Racer and some of the various stand alone products out there that will work with Ford ECUs.

It would be great to hear from people who have experience with either/both on their Focuses.

[jr_psychologist]

I'd actually really like to see an in-depth technical discussion of the ECU and tuning, particularly with respect to the adaptive learning stuff and to what extent it can interfere over time with what a tuner is trying to do.

[Lil_RedZX3]

Originally Posted by jr_psychologist

I'd actually really like to see an in-depth technical discussion of the ECU and tuning, particularly with respect to the adaptive learning stuff and to what extent it can interfere over time with what a tuner is trying to do.

+1

[gio_momma]

The ECU doesn't "know" there's manifold pressure. The fuel pressure sensor only knows what's going on in the rail in an absolute sense, not in a relative sense...as in 40PSI minus 10 = 30PSI net fuel pressure, so they have to richen the tables to compensate for the net loss of fuel pressure at some point.

The ECU and by extension, the driver module will keep it at the pressure its programmed pressure to a point (until it bypasses inside the pump), but it doesn't know how much to raise the pressure by itself because it doesn't see manifold pressure. You can only raise the pressure so much through software changes before the pump says "no way" and bypasses.

You can tell it to make a certain pressure under certain conditions (RPM, load, throttle or whatever you use) but those conditions are defined by what the computer can "see" or infer. Once you're at full-throttle (or whatever point) and whatever RPM it it programmed to make full presssure, that's all you get, pressure-wise, because the ECU doesn't know that the manifold pressure is above ambient (ie, positive manifold pressure).

[gio_momma]

Originally Posted by BUR_ZX3

So Joe what you're saying is that you have little to no experience calibrating the stock ECU... You wanna say tuning is tuning.... thats fine, but until you dig into the Focus ECU, then I don't think you really have any idea.

I've dug into it plenty...it's just that "tuning" a stock ECU, especially for boosted applications, is a marginal exercise at best. But in your rather limited experience, you would have no way to know that, now would you?

You can forestall the inevitable for a little while, but you're always going to make more power, more reliably with a proper ECU...plus, you can actually tune it yourself, instead of having to pay someone else to do it.

BTW Randytodd...a Focus ECU is no different functionally than any other Ford ECU.

[thekrux]

hmmm. i think from here and ff there are many people making over 300 whp with focus ecus. doesn't seem to be a problem for them.

[gio_momma]

Originally Posted by thekrux

hmmm. i think from here and ff there are many people making over 300 whp with focus ecus. doesn't seem to be a problem for them.

The Egyptians built the pyramids with some pretty crude tools and a lot of labor. There are better ways to do it nowadays.

The stock ECU stuff has its place for milder stuff, but for blown applications good results are elusive and expensive at $100 a "tune".

[FocusSportVP]

Now why would a Focus owner want to spend money on a stand alone when they could have the SCT Pro Racer?

The cheapest I could find the low end Haltech stuff was $700.

The cheapest I could find Petel was around $1800.

The Pro Racer is $678 and that comes WITH a lightning fast data logger ( 60-62 samples per second ).

Once a consumer buys the Pro Racer, they don't pay anyone anything to tune their car unless it's dyno time. They can make changes all day and all night, it's theirs and it's a one time cost. Most stand alones are much more labor intensive to install versus flashing the OEM ECU, too.

And I can't think of why a stand alone would be MORE reliable than something like the Pro Racer, which is just reflashing the OEM ECU. And the Pro Racer retains ALL of the OEM functions and scalars - not the case with the stand alones that I've experienced. Stand alones are a great option IMO for applications where you don't have something like the Pro Racer, but if you do, the Pro Racer is the clear choice for probably 95% of Focus owners out there that want to tune their car.

[gio_momma]

Fueling changes are simpler and more consistent, they're far easier to tune, have more options. They're intended to be used in blown applications. It's not a matter of trying to force them to work in a way they were never intended to. The problem is that the factory "functions and scalars" are not intended for what you're doing with them. A standard speed-density ECU can be tuned to near-perfect in a few pulls and be done with it...because they're made to be tuned.

The Pectel-style harness setup (or whoever wanted to make one that interfaces the same way) could be adapted to work any ECU with similar capabilites. This essentially turns it into a piggyback setup, rather than a true standalone. The harness they did goes in in about an hour and can be returned to stock in minutes (seconds, actually). The aftermarket ECU can do what it does well (run the fuel and spark tables), the stock ECU can do what it does well (everything else)...neither knows nor cares what the other is doing.

Any ECU option is cheaper than buying an engine.

If you have to pass emissions, then a CARB-appproved flash deal or the "black box" are going to be the only real options...but that's not what we're talking about here, right? The pro racer isn't any more smog/street-legal than a piggyback would be.

And most all ECUs have datalogging...if 60hz is "lightning fast" to you...LOL...you gotta get out more often. It's faster than some ECUs do, but not as fast as others.

[FocusSportVP]

Well, again for the cost involved, the Pro Racer is a great choice versus something like the Pectel. The only time I would think that a stand alone would be preferred is if you didn't want a MAF sensor.

If you can do basic math, there aren't any problems with making fuel changes with the Pro Racer - piece of cake.

You don't have to force anything to work for FI, either. I don't recall having problems with the fuel delivery ( other than fuel pumps ). Once you have a good understanding of the OEM data bases it's a pretty smooth process.

CARB? What's that?

[gio_momma]

Originally Posted by FocusSportVP

Well, again for the cost involved, the Pro Racer is a great choice versus something like the Pectel. The only time I would think that a stand alone would be preferred is if you didn't want a MAF sensor.

If you can do basic math, there aren't any problems with making fuel changes with the Pro Racer - piece of cake.

You don't have to force anything to work for FI, either. I don't recall having problems with the fuel delivery ( other than fuel pumps ). Once you have a good understanding of the OEM data bases it's a pretty smooth process.

CARB? What's that?

Well...I'm sure there are a few people out there that would disagree about how easy it is to get an NA ECU to work in a blown application. You wouldn't have to over-fuel cars for the "just in case" issues. You put it where you want it and it's there, you don't have to add 20% more than it needs.

Again, anyone can make a harness that will turn any ECU that will run 36-1 into a piggyback. It's not that hard to do and it's not as expensive as an SCT setup and a few "magic" tunes at $100 a pop. Some of the newer Haltech stuff is very capable and very affordable.

[FocusSportVP]

What is all this $100 for magic tunes business about?

And I'd like to hear from someone who couldn't get FI to work on their Ford ECU please. Do you know anyone? I really can't say that I've ever heard of such a thing. I'm genuinely curious about this. Anyone here on FJ perhaps?

[gio_momma]

You can obviously make it "work"...it just won't "work right". If you want to make power and have it live while doing so, the stock ECU isn't the best way to go. Of course, I don't expect you're going to be very candid about it, for obvious reasons. The Ford guys even gave up on doing it, because they found the factory ECU to be unsuitable...LOL...but FS has it down to a science. Where do you think all the Pectel piggyback stuff started???

Sooo...anyways...you work you way through the "functions and scalars" for free? Any aftermarket ECU will tune very quickly because it's MADE to be used in performance and blown applications and be tuned by an end user. Of course chips and flashers have a place, but they're far from well-suited for serious modifications and turbo/blower swaps.

[Dudley]

I think the whole standalone debate is all a matter of the car's intended purpose. For a daily driver or a dual-purpose car, keeping the stock PCM makes a lot of sense.

With the Pro Racer Package, I can pass my upstate NY OBD2 emissions test (with the 2nd O2 harness flopping around loose in the engine bay, by the way). I can retain control of the A/C and the alternator. If I had traction control or an automatic trans, that would be even more incentive to keep the stock PCM.

The EEC-V is pretty powerful. Here's what it cannot do:

There's no individual-cylinder fuel trim (individual-cylinder global spark retard is available, though)
There's no ability to change fueling based on engine load (the fuel tables use RPM and throttle position)
It can't pulse a nitrous solenoid or control water injection, etc.
The Focus "version" is not capable of using a MAP sensor.

I'm no tuning wizard, but I don't see the lack of a speed-density option as the end of the world. For DIY tuners like me, I dare say that MAF systems are superior because they're much more forgiving with power-adders. Add a turbo, the MAF sees the extra airflow, and the PCM calculates the engine load. With a MAP system, you'd have to reprogram your VE tables every time you change something that affects VE, right? That may be a piece of cake for a pro, but for hobby-level tuners it sounds like a huge PITA.

I left out the issue of real-time tuning, but I don't think that's a big deal, either. SCT doesn't offer real-time tuning, but it's theoretically possible to do it through the EEC-V's J3 port. In fact, I think the twEECer product has offered real-time EEC-V tuning for a while now, but I'm not sure about that.

Again, though, I think it's all a matter of the car's purpose. If you need real-time tuning, then chances are that your car isn't a daily driver. I mean, how many daily drivers are using standalone tuning? Not many, I bet. At the other extreme, I bet SCT has a huge percentage of the daily driver market. That's not a coincidence. Keeping the stock PCM is the logical choice for almost every street-driven Focus.

[gio_momma]

If you know where to look, you can always get a bogus smog check. I was talking about the legal issues, not whether you found some "Gomer" to pass you with disconnected sensors. It's not any more emissions-legal than an aftermarket ECU.

Besides, I'm not talking about removing/disabling the factory ECU, just tuning the fuel and spark tables with a different ECU. The body functions still work fine...the factory ECU still thinks it's calling the shots...it just isn't.

Look..if the stock ECU works for you, if it does what you want it to...good deal. It's just that there are better ways to do it. I dare say that if you've ever had the opportunity to work with both, you wouldn't be using the flashers.

As`for the "forgiving" part...you could also read that as "inaccurate". Either you put the fuel where it needs to be for a given condition or you don't. A speed density setup puts the fuel where you want it and it stays there. They know 10PSI from 15PSI and can be tuned accordingly.

[Dudley]

Oh, okay - I see what you're saying. With speed-density, you don't have the delay between when the air is metered and when it gets to the intake port. But again, how important is that for the average "enthusiast"?

My point was that, at the hobby level, the advantages of a standalone or piggyback ECU don't outweigh the hassles of installing the thing and getting it to cooperate with the stock components. For instance, has anybody rigged up a Pectel to work properly with traction control? It may be possible, but is it worth the trouble vs. just using the stock PCM?

It's a PITA no matter how you go about it - you can either accept the limitations of the stock PCM, or go to the trouble of installing a piggyback or standalone unit. But a big advantage to keeping as much OEM stuff as possible is that you can still take the car to a shop when you get in over your head. Again, that's not a problem for a pro, but it would be a nightmare for a lot of amateur tuners (like me, for instance).

I have zero experience with any tuning product other than the SCT Pro Racer Package, so I obvioulsy can't comment on how it compares to a standalone tuning solution. All I can say is that, for my needs, the stock PCM is by far the most convenient choice.

[Jerseyboy]

Originally Posted by gio_momma

I've dug into it plenty...it's just that "tuning" a stock ECU, especially for boosted applications, is a marginal exercise at best. But in your rather limited experience, you would have no way to know that, now would you?

You can forestall the inevitable for a little while, but you're always going to make more power, more reliably with a proper ECU...plus, you can actually tune it yourself, instead of having to pay someone else to do it.

BTW Randytodd...a Focus ECU is no different functionally than any other Ford ECU.

I guess someone needs to tell these guys that they are doing it wrong then. Factory ECUs! The HORROR!

http://www.motortrend.com/roadtests/...pe_comparison/

I agree that a standalone is easier to tune and has it's advantages (can read boost when a factory NA computer cannot) in some applications. They also have thier disadvantages. If you are willing to cut up your harness and install a standalone, have at it. It's not my thing. I've made plenty of power with factory processors.

I think if you toned it down a few decibles, people might actually listen to you rather then refute everything you say. There is some truth in what you say, but it is for specific applications. For a street driven, daily driver, I see no reason to ditch the factory processor. If it's a, drag only car, custom kitcar or sandrail, standalone all the way. Like I said, they both have thier places.


Jersey

[lourenco]

I like the pectel since I don't need to worry about the o2 sensors. I just had a 10.5 compression engine done by c-f-m. I am really thinking about driving around with 110 leaded gas or c-16 all the time with 25 to 30 psi of boost. I know with the stock ecu I would have to worry about the 02 sensor going out. I also wonder how the stock ecu would be able handle a very large load value. My car must be at 300% load or something, as I plan to make 430fwhp. The pectel allows me to adjust the timing and a/f ratio at the higher boost levels. I think the sct stuff maxes out at 200% or something.

I bought the sct proracer package for my mustang cobra awhile back. I think it was like $410 or so. It is a headache for me to clean up the maf function. It also took a little while for me to get used to it. I find the pectel to be more strait forward. One point I thought I had issues with it not working correctly, but I later found out my imrc was going out.

I am thinking about trying to do sct on my svtf to see if I am missing out of something, but I have a question for Randy about this. What do you think about my leaded gas and load issues? What has been your experience with that?

[OrangeSVT03]

I've used several versions of the ProRacer for the SVT in both RLA6 and YRF0 data formats.... the one thing I really didnt like as far as the data files went was in one version you may have a handy setting at you disposal and it'll be gone in the next version.

I also dont like the MAF count issue I had a couple of months ago..... changing the range on your MAF should NOT effect the pressure drop across the injectors.

But I do like not having to mess with all the little things like setting up your AC, for the "average" tuner I think the SCT PRP does a good job.

[Hocky]

Open loop speed density is the way to go....

[dimm]

Originally Posted by Hocky

Open loop speed density is the way to go....

Yeah until you hit a quick altitude change.

Speed density is ok IMO as long as the maps have the resolution you need (like the pectel).

It's not ok if your using a mega-squirt as a friend of mine has finally found out. The older map resolutions sucks for adjusting fuel and spark, the new version is something like 16x16, the old version was like 8x8 (which he bought and built for $150.00). I belive the accel dfi is 32x32 (hence the higher cost).

And to "turbo" joe morgan....I was wondering who this person was in this thread spewing the knowledge forth. Then I saw your name in your sig. Are you pimpin any products right now?

What is turboford sick of your ass already? (joke) :0

So joe your saying the new haltec piggy back setup has gotten nicer? I haven't seen it in a while.

Anybody ever heard the rumor of if the piggy back system ecu is not as quick as the oem ecu than the oem can overide it? Like to put that rumor to rest.

Plus it sucks to hit a bad bump and have your chip come a little loose in the J3 port of a ford ecu. Back to stock in a jiff!!!! (very rare cases but it has happened)

Several tuning books I've read will preach to stay mass air metered whenever possible (as stated by someone above...more forgiving when it comes to quick altitude changes and other issues). They then go on to state most tuners want to switch to speed density because there "easier" to tune. At the time some of these books were written when most standalones did not have the resolutions that they do now for the speed density set-ups.

Alot of newer standalones have a self tune button. Hold it down for 5 seconds when starting the car and it gives you a base map to start from. I belive almost all haltecs have this ability now same as efi systems, sds may have it now also. I also belive accel dfi system has a feature similar as does.....altrnoik (I think I have the name wrong but it starts with an A).

The tweecer is a cool unit as long as most of the code is hacked for your application there is certain things that are off limits because they haven't hacked the code yet. Plus certain aspects of fuel and spark in some applications you have very limited control, in other applications you can do some serious damage because you have full control of the ecu. You can't tune the tweecer real time. You can switch programs real time though.

Next on the table....what do we all think about s/c vs. turbochargers?

It comes down to prefrence and what you want to do with your car for the standalone vs. piggyback vs. sct pro-racer debate IMO.


Any body check out the newest specs on the greddy ultimate e-manage? It's very nice for a piggy back(application specific though). Data logging is quick too.

Anybody ever use a F.A.S.T system (a.k.a. old felpro)?