PortFueler EMS (Engine Management System) Q&A

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  • We’ve seen a bit of buzz and have been fielding increased interest in this new development, so I’d like to set up a Q&A thread here, and share with you folks the detail you’d like to learn on this exciting new engine management solution.





    Our new PortFueler EMS System for Slingshot is a unique offering in engine management. In cost and features, it's intended to fit in between a canned, unadjustable PCM tune, and a full programmable engine management solution like Haltech. It is a very proven concept which we have used for years with great success on applications from Dodge SRT-4 to Suzuki Hayabusa. This newest iteration of it for Slingshot is also accompanied by the introduction of our all-new PortFueler EMS module, which adds more capability than ever before.


    The essence of it is simple enough: we add four additional injectors (via the StreetRace intake manifold), and the PortFueler Module, which is monitoring engine parameters, takes it from there. Of particular note is that the stock unflashed PCM and injectors stay in place, functioning as they ever did with their crisp, clean response. As the engine seamlessly enters the boosted condition, the PortFueler injectors come alive, providing a 100% tunable fueling and ignition solution. PortFueler can be used on either turbo or supercharged applications.


    Two injectors per cylinder is a most desirable combination, and found on most all high HP boosted cars today. Splitting or staging the fuel in this fashion empowers us to use a much smaller injector for the machine to idle and drive about at low to moderate speeds. The advantage is that smaller injectors are more crisp and defined, and more consistent, in their low-speed capability than running a single large injector per cylinder.


    As such, the PortFueler-equipped machine will idle as crisply as stock, with the same excellent drivability as stock. We’re not exaggerating when we tell you that this system idles and low-speeds better than any other boosted Slingshot we’ve encountered with large single injectors. It is quite evident, noticeably smoother with a nice stock 800 RPM idle speed and unrivaled driveability.


    But when it’s time to pour to the fuel to it, you’ll have all the adjustable power you’ll need. The PortFueler EMS module is 100% tunable, individually for all boost levels and RPM points, on standard fuel and ignition map tables. Manufactured for Hahn RaceCraft by automotive electronics leader AEM, it is easy to learn, and supports all AEM datalogging and gauge logging functions, as well as features its own internal datalogging.


    In its first trial, on @shortremovers spectacular Sling earlier this year, we progressively mapped out the entire boost curve a couple PSI at a time from 0 to 20 PSI boost, where it recorded almost 500 engine HP, putting 413 HP to the rear wheel…on pump gas.


    While in doing this, we wished to prove the system’s ability to support high HP and grab some some max-effort bragging rights, it’s certainly just at home on a stock engine with a standard boost level turbo or supercharger…and as it is eminently capable of also handling higher power levels, it’s a perfect choice should one have aspirations to someday move up to a built engine and more HP.


    Now that you have the basics, these two webpages show the products:


    Slingshot StreetRace Intake Manifold
    PortFueler EMS


    I’ll be here all day, so I figured I’d toss out some basics and see what questions come back. I’ll riff off of your interests and add more data and detail via my answers. Talk to me!

  • I’m thinking I may recognize this build!!
    It is definitely everything Bill has stated.... Sure enough love the stock idle and drivability of this build, being able to just cruise around as if nothing has been done under the hood, and how it comes alive when you decide it’s time to move on down the road. It does come to life when the right foot gets heavy..
    If there is anyone in the south central Oklahoma or north Texas area who would like to see it to believe it, just give me a shout, we can surely arrange something to make it happen!!

    Powered by Hahn Racecraft BFB Motor, Stage V Turbo, Street Race Manifold w/ Port Fueler. WHP 4++ LOADED!! :WHITESS:

  • Is this a piggy back system or is there a new tune that is required to run this?

    CO D12


    Hahn SST stage 2X PRP Seats Sparco Steering Wheel (Not SLR) w/ NRG 3.0 Quick release Canadian Headlight R-Shot Accessories Windscreen Rear Protection Plate by Slinglow NASCAR Windshield Kenwood Double DIN SSV head pods with Polk DB 6.5"s SSV Works Subwoofer enclosure w/10" JL Audio Kenwood Amps Slingshot Side Storage 11 Piece Mat Kit TD Canvas top TD lip spoiler 22" Asanti Wheels TD sway bar TD shifter boot cover & parking brake Graphics by AMR Racing QA1 front TrakHamr rear

  • Its'a piggy back system, that leaves the stock ECU alone, the dealer can reflash it all they want. It will not effect the PortFueler configuration.

    Yes, this is defined as a piggyback system, which means it works alongside and in conjunction with the stock PCM.


    An additional advantage is this latest PortFueler EMS configuration, which in addition to a host of new features brought by the new AEM module, also uses the stock PCM's adaptive capabilities for climatic/weather changes. As the PortFueler injector pulse is determined and mapped as a percentage of stock fuel injector pulse, when the stock PCM adds more fuel for colder temperatures/denser air, so will the PortFueler injectors deliver accordingly more fuel. The converse occurs as temperatures warm and air grows less dense, and teh stock PCM leans the mixture accordingly...the PortFueler injectors will follow suit.


    This adaptability also means the PortFueler EMS will adapt fueling to accommodate large changes in altitude well.


    Ignition timing adaptive capability in the stock PCM also carries through to PortFueler, as like the injector operation, its ignition timing changes are also performed as a percentage of stock timing. When the PCM retards in real-time, or changes its adaptive timing tables over time for weather change, so are these refinements reflected in the PortFueler EMS.

  • Does that mean that any current PCM tuned for boost has to be reset to factory setting?

    CO D12


    Hahn SST stage 2X PRP Seats Sparco Steering Wheel (Not SLR) w/ NRG 3.0 Quick release Canadian Headlight R-Shot Accessories Windscreen Rear Protection Plate by Slinglow NASCAR Windshield Kenwood Double DIN SSV head pods with Polk DB 6.5"s SSV Works Subwoofer enclosure w/10" JL Audio Kenwood Amps Slingshot Side Storage 11 Piece Mat Kit TD Canvas top TD lip spoiler 22" Asanti Wheels TD sway bar TD shifter boot cover & parking brake Graphics by AMR Racing QA1 front TrakHamr rear

  • Does that mean that any current PCM tuned for boost has to be reset to factory setting?

    Not necessarily. We are developing a tune which will accommodate such machines. However, the optimum approach would be to flash the PCM back to stock, and re-install the stock injectors. This will restore the super-crisp operation of the stock injectors for superior low-speed and idling, and enable one to confidently install any future updates from Polaris to the stock PCM without having to be concerned about "writing over" one's
    turbo reflash.

  • Not necessarily. We are developing a tune which will accommodate such machines. However, the optimum approach would be to flash the PCM back to stock, and re-install the stock injectors. This will restore the super-crisp operation of the stock injectors for superior low-speed and idling, and enable one to confidently install any future updates from Polaris to the stock PCM without having to be concerned about "writing over" one'sturbo reflash.

    This actually feels better to me. is the 2 bar map sensor still required? I would assume so? Bill I am going to message you on FB later.

    CO D12


    Hahn SST stage 2X PRP Seats Sparco Steering Wheel (Not SLR) w/ NRG 3.0 Quick release Canadian Headlight R-Shot Accessories Windscreen Rear Protection Plate by Slinglow NASCAR Windshield Kenwood Double DIN SSV head pods with Polk DB 6.5"s SSV Works Subwoofer enclosure w/10" JL Audio Kenwood Amps Slingshot Side Storage 11 Piece Mat Kit TD Canvas top TD lip spoiler 22" Asanti Wheels TD sway bar TD shifter boot cover & parking brake Graphics by AMR Racing QA1 front TrakHamr rear

  • This actually feels better to me. is the 2 bar map sensor still required? I would assume so? Bill I am going to message you on FB later.

    No, we'd effectively revert to stock PCM tune, stock injectors and stock 1-bar MAP sensor. The PortFueler EMS module then takes over boosted operation via its own internal MAP sensor that can monitor up to 27 PSI of boost. Thanks, I look forward to your message.

  • No, we'd effectively revert to stock PCM tune, stock injectors and stock 1-bar MAP sensor. The PortFueler EMS module then takes over boosted operation via its own internal MAP sensor that can monitor up to 27 PSI of boost. Thanks, I look forward to your message.

    Does that come with the package price? If not, might be something you want to look in to for those that have already been boosted and then looking to swap out. ;)

    CO D12


    Hahn SST stage 2X PRP Seats Sparco Steering Wheel (Not SLR) w/ NRG 3.0 Quick release Canadian Headlight R-Shot Accessories Windscreen Rear Protection Plate by Slinglow NASCAR Windshield Kenwood Double DIN SSV head pods with Polk DB 6.5"s SSV Works Subwoofer enclosure w/10" JL Audio Kenwood Amps Slingshot Side Storage 11 Piece Mat Kit TD Canvas top TD lip spoiler 22" Asanti Wheels TD sway bar TD shifter boot cover & parking brake Graphics by AMR Racing QA1 front TrakHamr rear

  • Does that come with the package price? If not, might be something you want to look in to for those that have already been boosted and then looking to swap out. ;)

    We are working off a general assumption that most folks will hang onto their stock injectors and MAP sensor 1-bar from their original forced induction installation, but for those who don't, they are also plentiful and inexpensive enough as take-offs from other such installations.