Do you really need a 'tune' or is it bs

[General karthief]

I understand the aftermarket ecu gig, that's not part of the discussion, it is the best way to 'tune' for optimal operation/efficiency, that's why the new technology is programmable, the discussion is about the stock ecu. I like the exp!anation noobz gave, I did read it twice but I think I see his point.

 

[HemiRick]

The Megasquirt plug in 5.0 ECU is $839, pay for 2 tunes and you could have gotten a ECU that will automatically tune for whatever you choose to change/upgrade in the future, assuming you also get a wideband O2 sensor. And you can do away with the need for a MAF sensor as MS runs a 5.0 fine on speed density. So yes today to pay for a tune IMHO is kinda wasting $$$, on a 1 time solution vs. a permanent solution.

 

[Noobz347]

I understand the aftermarket ecu gig, that's not part of the discussion, it is the best way to 'tune' for optimal operation/efficiency, that's why the new technology is programmable, the discussion is about the stock ecu. I like the exp!anation noobz gave, I did read it twice but I think I see his point.

This is good because remember:

The digital portion was created specifically from the physical characteristics of the mechanical devices. The devices themselves determined the values, not the other way around. It stands to reason that if you change those mechanical devices in part or in whole that you should also change that part of the digital component that holds the registered values of those mechanical devices. In other words: Describe the new MAF or new injector in a language that the original ECU understands. This is the basic concept of chip tuning something like an A9L. We haven't touched the program itself. All we've really done is swap some register values in order to define the components in our combo.

Of course, the alternative is to either modify the input signal of a sensor to fool the ECU into thinking all it normal or modify the output signal to make the ECU think it is signaling the OEM component (a MIL eliminator is a great example of this... No cat, no problem).

Now, I will give the Nay-Sayers their due... There were many years where modifying an ECU in this way was either not possible (the hardware didn't exist), not cost-effective compared to other means, and not expected to provide good driving manners in a school zone through a Windsor pumping out NASCAR level power levels and beyond.

As far as the modern age has pushed the 'cubic inch', accuracy and resolution are more important than ever. Particularly, if you want it to cruise nicely.

 

[marcelo]

and what exactly is a Tune with an original ECU ??? how you gona tell your original ECU that you changed from original 19lbs Injectors to 30 lbs .. for example? you go to 75mm maf and 75 TB change your intake Heads, bigger cam, Injectors,LT headers, stroker etc and someone really wants to tell me that your 30 year old ECU will handle all that correctly??? Dream on ....mine didnt ..and tried 2 different originals ..engine was running ass lean ..wide band showed AFR readings up to 18:1 and worse... so I am happy with my MS and my ..some kind of expensive Engine.. too ...

 

[Noobz347]

and what exactly is a Tune with an original ECU ??? how you gona tell your original ECU that you changed from original 19lbs Injectors to 30 lbs .. for example? you go to 75mm maf and 75 TB change your intake Heads, bigger cam, Injectors,LT headers, stroker etc and someone really wants to tell me that your 30 year old ECU will handle all that correctly??? Dream on ....mine didnt ..and tried 2 different originals ..engine was running ass lean ..wide band showed AFR readings up to 18:1 and worse... so I am happy with my MS and my ..some kind of expensive Engine.. too ...

You do this with a chip. One like the one I have installed. The one that has new registers for my 80mm PMAS MAF, 42 lb injectors, 1 3/4 long tubes, and 80mm TB, all over a 347 C.I. stoker using a 2.2L Kenne Bell as the intake.

It's a 4-bank Chip. One of those banks has a "Valet" tune. I got it done at Hi-Tech Performance in Minneapolis some 15 years ago.

someone really wants to tell me that your 30 year old ECU will handle all that correctly??? Dream on

Yes... That is exactly right. I believe mine was made by SCT and is [still] on the market.

 

[Noobz347]

I also possess an Anderson Ford PMS for another of my cars. It has a "piggy back" mode that operates just as I described.

In "stand-alone" mode, it lacks the OEM ECU's ability to make minor adjustments.

I mention this because it was was a hot contender against the chiptune that I got. The problem was that then it was insanely expensive.

 

[General karthief]

Back it up guys, going to an aftermarket ecu is a 'captain obvious ' move because of the infinite tuning capabilities, when going to stuff that is too big, like 30lb injectors and then have it 'tuned' because it don't work right is like putting a 750 cfm double pumper on a close to stock engine, sure it can be made to work but it's still wrong for the setup.
This is what I mean, does a properly planned 300-350 hp car running a stock ecu need a tune, can it run and drive fine without?
I'm not talking about getting every last horse/torque number out of it, it's not a race car, granted I do believe the 350 hp mark is on the extreme end of the 'no tune' spectrum, and I'm not say'n that even a mild engine can't benefit from a PROPERLY done tune.

 

[Monkeybutt2000]

Before the car surged and bucked at low rpm cruising. It had a intermittent surging idle. It we generally hard to drive. I ensured all my sensors were good before going to the tuner. Now this was a while ago, so its tough to remember. He set timing and verfied fuel pressure. Asked about modifications, thermostat, and spark plugs. Everything checked out so he plugged in with his laptop. I would guess he could see all the data from sensors and verified they were working. He wasn't the most talkative guy about what exactly he was doing.. I chalked it up to working his magic. He is renounced as an excellent ford tuner in the northeast and one of the only that actually tunes these old cars. I know that he changed the timing curve and fuel table, but not what else. For reference I had edlebrock heads and intake, unknown cam, 30lb injectors, and a BBK fenderwell CAI and matching MAF. First pull was 250hp and the last was 299hp. I also talked to him quite a bit about further modifications, what he's seen work well, how to make more power, and other general mustang stuff. Money well spend for me.

He plugged his laptop into .....what?

 

[Noobz347]

You could get every last horsepower out of either option.

What makes kits like the MegaSquirt and other stand-alone systems really attractive these days is that "infinite tuning capability" that you mentioned.


The other things that help are:
Prices on these systems are now manageable (they are compatible with many kinds of sensors making it cheaper to produce one machine that is suitable for many vehicles)
Improvements in hardware and software have put them in the hands of enthusiasts and not just tuners
A9x computers are now hard to find and expensive
Newer systems have generally higher buss speeds and enough excess core computing power to do other things like... Run a transmission (for example) or logging data (which the A9x will not do).

 

[Monkeybutt2000]

The Megasquirt plug in 5.0 ECU is $839, pay for 2 tunes and you could have gotten a ECU that will automatically tune for whatever you choose to change/upgrade in the future, assuming you also get a wideband O2 sensor. And you can do away with the need for a MAF sensor as MS runs a 5.0 fine on speed density. So yes today to pay for a tune IMHO is kinda wasting $$$, on a 1 time solution vs. a permanent solution.

What ecu is this?

 

[HemiRick]

What ecu is this?

Ford Mustang FoxBody 5.0 1986-1993 MSPNP Gen2 Plug and Play ECU

Ford FoxBody Mustang PNP ECU - MSPNP Gen2 Plug and Play for the 1986-1993 Ford Mustang 5.0 and 1986-1988 Thunderbird 5.0, installs in under 1 hour.

www.diyautotune.com

or even better for $475

MicroSquirt® for 1986-93 Ford 5.0 Mustang – EFI Source

EFI Source supplies Goldbox, MegaSquirt, MicroSquirt, LS, Hemi, Harness, and other programmable EFI systems and products o the performance minded automotive community.

www.efisource.com

 

[marcelo]

ok... you gonna CHIP tune the Original ---- ok ...but its still an old ECU .. like using a Chip tuned 30 Year old cell phone or a 30 year old Laptop..this is ok if you mod your car and let it like it is ... I m doing a lot of changes ..also have 2 different engines for my car ... so I do change a lot the tunes ... Chip tune is no option for me ...but ok with the Chip tuning the Stock ECU

 

[General karthief]

ok... you gonna CHIP tune the Original ---- ok ...but its still an old ECU .. like using a Chip tuned 30 Year old cell phone or a 30 year old Laptop..this is ok if you mod your car and let it like it is ... I m doing a lot of changes ..also have 2 different engines for my car ... so I do change a lot the tunes ... Chip tune is no option for me ...but ok with the Chip tuning the Stock ECU

I'm not sure I follow you, and I'm not sure you get the point of this discussion.

 

[marcelo]

I'm not sure I follow you, and I'm not sure you get the point of this discussion.

This is what I mean, does a properly planned 300-350 hp car running a stock ecu need a tune, can it run and drive fine without? I follow you yes .. and as I said .. mine did not worked fine with the Stock ECU ...and i tried 2 different ..it was running way too lean.. so in my opinion you cant drive fine and at some point you mabe will hurt your engine with a stock ECU without a Tune or a Chip or a better Option ..... ok?? but thats my experience ...sorry for confusion..

 

[nickyb]

I'm not sure I follow you, and I'm not sure you get the point of this discussion.

Need is like more of an opinion.My needs,your needs will differ.Some can live happily without a tune,even if it runs rough as sheeet.And then some what a perfect idle , super smooth all the way up the r.p.m.s. I say build it and see how you like the out come without a tune and if you " need" a tune you can decide on a tuner,achip,or a new ecu. To each his own we 'll all get blown.

 

[junkyardwarrior]

most aftermarket systems utilize speed density

on a street car, a maf is preferred

Look at OEM. There ain't no SD systems in OEM that I know of, all maf, at least since the 1990's (which are antiques)

ask yourself why

I'm pretty certain that if OEM's could save a $20 MAF and still provide the good NVH, fuel mileage, drivability, and reliability they would most definitely run the "simpler" SD system. $20 saved is a generality. If they built 300,000 cars all the same with SD (no maf), for a savings of $20 each, that's a savings of $6,000,000. I'm certain that if an automotive manufacturer was given the opportunity to save $6M, they'd do it. But $20 is a VERY general figure to throw out there, I would venture to guess it'd be much more substantial once you figure in the wiring, ecu, intake piping, airbox, and a bunch of other things that benefit the maf system and the sensor itself.

Actually this subject reminds me that I need to order some parts, doing a T4M0 94-95 GT computer in my 93 coupe 4 cylinder so I can run a slot MAF with it (turbo). The VAM system works ok but it's very limited and CRUDE.

 

[HemiRick]

You're forgetting that OEM's have to comply w emissions standards and their goal is not to make the most power. Doing away with the MAF and SD are fine for making power. Drivability is not an issue either.

 

[marcelo]

thats the advantege of the MegaSquirt2PNP...you can choose what you want ! just plug and play..

 

[Blown88GT]

MS also allows use of SD or MAF or both. I use both, basically, MAF for fuel & MAP (SD) for spark.
Why did I do this?
Why delete a new MAF housing with calibration tube when it can be put to good use?
Turns out, it actually works better with forced induction for street driveability.

 

[Boostedpimp]

uh my opinion on this topic wouldn't go well with the masses so i'm just going read the comments