Speed Density Or Mas Air What's The Benifits?

Discussion in 'Fox 5.0 Mustang Tech' started by 1200gt, Sep 19, 2013.


  1. f8tlfiveo

    f8tlfiveo My wife likes my spool and blow-off valve.

    Joined:
    Aug 9, 2007
    Messages:
    1,337
    Likes Received:
    59
    Trophy Points:
    49
    Location:
    Lancaster, PA
    I do not do my own tuning, but if you have time to mess with it, I think it can be something valuable to learn. I am going to do it eventually but at this point in time I have no time. I bought a book by Greg banish that was a good intro to tuning.


    Sent from my iPhone using Tapatalk
  2. FastDriver

    FastDriver Mod Dude

    Joined:
    Sep 6, 2001
    Messages:
    2,968
    Likes Received:
    107
    Trophy Points:
    74
    Ok Mad, that makes a lot of sense. I think WOT timing tuning could be done if you could overlay RPM vs. time logs. If all other factors were the same, you could see how timing changes affected the rate of acceleration just like guys that tune on inertial dynos. So I wondered if the guy was doing that, but I'm not sure if you have the capability of doing this or if the measurement would be precise enough.

    I'm guessing that the timing tables are just based on another car but remain conservative enough to prevent detonation in any car. That probably means it's leaving a little power on the table compared to a dyno tune particularly at partial loads. For most of us, drivability and WOT acceleration are what matter most. Improving partial load tunes should help in efficiency and response, but ultimately if you need more power than 10% throttle, you just mash the peddle a little more.

    Do you ever hear any detonation at partial load?


    Sponsored Ad

  3. madspeed

    madspeed Colonel Mustard Mod Dude Founding Member

    Joined:
    Nov 30, 1999
    Messages:
    6,114
    Likes Received:
    708
    Trophy Points:
    164
    Location:
    Somewhere on a hill in the PA wildnerness
    @Gearbanger 101, nah. If you've got any common sense you can load a tune. As far as the tuning itself, if you truly want to do it yourself, ten i'd imagine a fairly big learning curve. As mentioned, there's tons of info over on eectuning.org. I chose to stay out of the tuning game and let that part up to a pro. Just by playing around with the binary editor and eec analyzer ooking at my datalogs, I am starting to understand it a bit.

    @FastDriver, I am sure Willie has a pretty good understanding of the tuning proces on these cars, as that's his specialty. Before writing my base tune, he took all the details of my engine, drivetrain, driving style, intended purpose etc. Now i'm sure he has a huge compilation of tuning files and likely took a base tune and tweaked it, but that's juat fine with me. I can say my car idles and runs and drives smoother than it ever did. Part throttle tip in is smooth as glass, and wot is pretty badass, for a stock block anyhow!
  4. FastDriver

    FastDriver Mod Dude

    Joined:
    Sep 6, 2001
    Messages:
    2,968
    Likes Received:
    107
    Trophy Points:
    74
    Please don't take me the wrong way. It's all assumption and conjecture on my part and not worth the electrons used to store my rambling posts. I'm sure his understanding is beyond reproach too, man. If the guy's got a good reputation, then he clearly hasn't blown a lot of people's cars up and he obviously got them something they were satisfied with. I'm just trying to learn about this stuff and am hypothesizing on things that are starting to make a little sense to me. I'm sure he's done a very good job for you. I think these guys who have done hundreds or thousands of cars can get very close without putting it on a dyno, or getting feedback from EGTs. Most of the time, they have seen several very similar combinations, and the tune is not going to be radically different. It's obviously not going to be identical either though.

    Brian, it's the EEC that's complex whether you have a quarterhorse or Tweecer. I used Binary Editor and EEC analyzer with my buddy's tweecer on a '95 twin turbo. Even with a datalog, sometimes it's hard to figure out which table or modifier the EEC is using to command a value. I believe the quarterhorse uses the same software and modifies the same base tables in the EEC.
  5. Gearbanger 101

    Gearbanger 101 we love us some gays up here Super Mod

    Joined:
    Aug 11, 2002
    Messages:
    13,984
    Likes Received:
    621
    Trophy Points:
    164
    Location:
    Ontario, Canada
    I take it the $349 does not include a wide band as well?

    So basically what you're saying is....unless I have someone doing the tuning for me, keep saving up for a PMS.
  6. FastDriver

    FastDriver Mod Dude

    Joined:
    Sep 6, 2001
    Messages:
    2,968
    Likes Received:
    107
    Trophy Points:
    74
    Unfortunately, I'm not familiar with the PMS. I think my recommendation is all or nothing. Either pay a tuner and use their preferred system, or commit to learning and buy a system that allows you to tune all of the tables. To the guys who don't want the risk or ass-pain involved, I would recommend that you pay a professional and use the system they know best. To the DIYers, know that even after you've worked it all out, you will need to rent a dyno if you want to perfect the tune.
  7. 1200gt

    1200gt Member

    Joined:
    Nov 30, 1999
    Messages:
    300
    Likes Received:
    20
    Trophy Points:
    19

    Good points to hear.

    The one fact is, I have no experience at tuning - heck I wouldn't know where to begin. Chances are I'd take my car to someone who'd pick up on these facts and they'd empty my pockets. I'm sort of trying to get my mind around what tech to expect to get involved when tuning my SD EEC as well as what cost I should hold close to paying.

    Now for fiddling with the heads and other stuff: I do plan to make the normal host of mods, as listed above. I do already have the A9L, the wiring harness, MAF Meter and other peripherals already in my possession. my car happens to be an 86GT, so the heads are up for change along with piston swaps in some form.

    I hear the awesome info about SD being a viable option now, as Gearbanger says: Tech has come a long since the 90"s.

    I guess what I am really wondering is: Would a complete No-knowledge-of-tuning guy like myself be better off installing all of the MAF conversions parts that I have for the sake of little to no fiddling with the tuning stuff orrrrrr, should I just swap all my intended parts and go for having someone tune the car SD to the parameters of my new parts package. My initial thoughts were that the MAF conversion done well would leave me in a position where I would not need a "Max Tune for Power" as the Wide range of tolerance built into the MAF OEM tech would suffice for street duty.
  8. FastDriver

    FastDriver Mod Dude

    Joined:
    Sep 6, 2001
    Messages:
    2,968
    Likes Received:
    107
    Trophy Points:
    74
    If you're going to get a tune or tune yourself anyway, it doesn't matter, IMO. If you want more leeway in the system to be accomodating of changes, go with the MAF.

    I can't speculate whether you're capable of learning to tune and/or if you want the hassle of it. Only you can answer that question.
  9. 1200gt

    1200gt Member

    Joined:
    Nov 30, 1999
    Messages:
    300
    Likes Received:
    20
    Trophy Points:
    19

    Thanks FastDriver. These comments answer my questions and speak towards addressing my concerns about the whole tuning thing. I believe other running OE Speed Density, who don't want to get involved with the expense, not to mention the calculative guess work of a Tune as well as Dyno Tuning their car, will find your comment very helpful.

    Thanks to all the other guys who thru in their 2 cents. I appreciated hearing all views about my options. One of the cool thing about these cars is that we has so many options to choose from and a large community of friends to help out when we need to make choices or need to make repairs.

    I have decided to install all of my MAF parts with hope that there won't be any tuning needed to get it running in a reasonably normal OE operation. I believe I should be able to bring the car to within specs of the OEM Fox MAF cars. That will do for my street use applications and the added parts will allow me to at-least get out of the way of a Yugo! Maybe once everything is settled down and I run across a good Tuner, I'll give it a go.
    jrichker likes this.
  10. Decipha

    Decipha Member

    Joined:
    Aug 22, 2007
    Messages:
    57
    Likes Received:
    9
    Trophy Points:
    19
    Location:
    New Orleans, LA
    SD is fine and can be tuned just as well as a MAF setup the reason why it used to be such a popular swap was because there was no tuning support back in the day

    anyone that claims to have a tune that doesnt modify the spark tables is not properly tuning, tuning requires dialing in spark and fuel, spark is the most significant factor in performance

    you do not have to be an IT engineer to reprogram a ford ecu, its nothing more than a simple calculator

    24lb injectors are too small for any healthy headed 302, ive NEVER tuned a 5.0 with aftermarket heads that didnt outflow 24lb injectors

    the old eectuning forum has been down over a month now, im not sure when or if its coming back up

    back to the SD, the factory ford SD ecus cannot read boost, if you intend on boosting one you will have to swap to mass air

    the beauty of mass air is that you dont have to get a retune so long that you dont excees the maf and injectors range, you can tune it N/A then put boost on it later without having to retune, this of course only applies if your tune is dialed in correctly

    i recommend dropping the few bucks on the QH and tuning it yourself, its only $250

    however if you decide tuning just isnt for you then you can simply just pay someone to tune it for you, the QH gives you the ability to make any changes you wish

    Or the other options as mentioned in the previous post is to just get a mail order tune, with a known maf curve any knowledgeable tuner can setup the o2s to dial in your fuel even at WOT thus a wideband and a dyno wouldnt be needed

    and as for the other comment about dialing in spark over datalogs, its as simple as looking at the rpm, airmass, and throttle position to see how much loading is on the engine, knowing the MBT for the setup you can very easily approximate the optimal timing to update the spark table

    if your serious about tuning or would like to get more info to be better informed of whats going on, the most detailed explaination is on my website

    http://www.efidynotuning.com/ford

    I recommend to give all them write ups a good read when you get time, the pre tuning info is very important to read over BEFORE getting a tune

Share This Page