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Piggyback Installs, Exhaust Valves and Boost by Gear – Haltech Q&A Episode 25

September 5, 2019

Hi and welcome to the first Haltech Q&A
for 2018. This is a segment where you ask the questions
and we give you the answers. Our first question today comes from crow4ever
and they ask: Is it possible for the ECU to control
an exhaust cut-out butterfly valve? Well, Crow, the answer is yes. Some of these butterfly valves or these
exhaust bypass valves are actually available in standard cars. Some of the
European cars have them and they bypass some of the mufflers in order to make
them quicker or make them sound better. In the Haltech system we can
control these valves using some of our generic output tables. What we’ll do
is set up a generic output table that’ll go to your valve controller, so that when
we either press down on our throttle pedal, or we reach a certain amount of
boost pressure or a certain amount of RPM it’ll then activate the controller
the valve will open in order to get more exhaust flow or more noise out of your car. Our second question today comes from Kirk W… and he asks: What is a piggyback
installation? Kirk, this is a really good question and truthfully one that we
don’t actually get asked that much but one that I agree is certainly something
that we need to talk about A “Piggyback” ECU installation can be one of two things. The first one we’ll talk about is a “signal bender” style ECU
installation. That’s referred to as the first style of piggyback and the way
that style of system works is by intercepting the crankshaft sensor so
that we can intercept how fast the computer thinks the engine is turning so
if it we can speed it up or slow it down by intercepting the crank sensor signal
as well as intercepting or cutting into the load sensor so that might be the
throttle position the air flow meter or the manifold pressure. By cutting into
that signal we feed the sensor into an ECU and then out of the ECU back to a
factory computer. We can then adjust how much load the
computer sees. That’s why it’s called a “signal bender” because we’re
bending or we’re manipulating the factory senses in order for the factory
ECU to see a different load and then give us a different fueling or different ignition value. The second style of piggyback ECU
installation, which is a lot more popular is where we leave the factory computer
in place but we also wire in a full standalone ECU. The full standalone ECU shares all of the sensors with the factory computer. So that would be the crank sensor,
the cam sensor, the air temp, the coolant temp, the throttle position,
the manifold pressure. So both computers are looking at all of the sensors.
We would then cut the injectors and the ignition and maybe the cam control as well off the factory computer and allow that
aftermarket ECU to control those things. So now you’d end up with a factory
computer that’s got all the sensors going into it but not controlling fuel
and ignition. Whereas the aftermarket ECU
would be controlling the injectors, the ignition and the cam control. The benefit of doing it like this, is that we can leave the factory computer there and it might still be controlling all of the dash,
it might be doing the air conditioning system, it might be doing a factory
automatic transmission. So that way we can share the load
between the two ECUs. We can let the Haltech ECU or the aftermarket ECU control the engine and the engine power. And the factory ECU is left there to control the rest of the car. Our last question today comes from Jarmo: Is it possible to do boost-by-gear
on my R32 GT-R without adding any extra sensors? Jarmo, the answer is yes. On
your R32 GT-R we should have a speed signal going into the ECU so that way we know our road speed. You’ve also got engine RPM because we’ve
got our crank angle sensor coming in So because we know the road speed and we
know the engine RPM, the one thing that we need to enter into the ECU is our
gear ratio. That gives us a relationship between the road speed and the engine RPM. So that at any time we know what
gear you’re in. So it’s that simple. In our ECU you would cruise, drive along,
be online with the ECU, go into our Gear Setup cruise along in first gear – press READ.
It’s that simple! Get into the second gear, cruise along
at a steady RPM – press READ. Do this for each gear that you’ve got.
If you’ve got an R32 GT-R, it’s a five-speed. Once you have done that APPLY and OK. From there, whenever you choose a gear
that gear ratio will let the ECU know exactly what gear you’re in
so you can then do boost-per-gear. You can also display that on any of your
CAN based Dash systems. Well that’s all the questions we’ve got today.
We’re always looking for more questions So if you’ve got one you’re thinking
about right now… Leave them in the comments below,
jump on our Facebook page or is probably the easiest way
to give us your questions. When we get them – keep on watching,
we will definitely be answering them in the upcoming videos! My name is Scott. As always, thanks very much
for watching and I’ll see you next time!


  • Reply Benjan Bantjes April 6, 2018 at 2:39 am


  • Reply Benjan Bantjes April 6, 2018 at 2:47 am

    What sensors will I have to add to a cressida to do launch control and rolling anti lag with a elite 2000?(r154 transmission)

  • Reply kv553683 April 6, 2018 at 2:52 am

    Second lol

  • Reply eumoria April 6, 2018 at 3:08 am

    😀 276th! Editing and graphics are great 🙂 Difficult to make tech videos interesting keep up the good work!

  • Reply CorndogBrownie April 6, 2018 at 3:50 am

    Love the farm truck hat in the background

  • Reply AlexSerban April 6, 2018 at 4:44 am

    awesome tunning fork ! 😀

  • Reply Alex Strömberg April 6, 2018 at 4:51 am

    How many Volvo inline 5 do you guys see getting a haltech?

  • Reply TheRealToykilla5150 April 6, 2018 at 6:38 am

    Would it be possible to have the halTech ecu control the emissions system like EGR valve and other vacuum solenoids? Would it be possible to add an OBD2 "read only" data port?

  • Reply Kevin Chetram April 6, 2018 at 7:37 am

    Hey Scott do u guys ship overseas. Eg: to a caribbean island like Grenada where am from . And if yes how can I purchase ur product

  • Reply Ryan Adams April 6, 2018 at 10:31 am

    Hey just wondering if the 1500 elite can be run on a 09 swift sport and if so do you know the pin out for the oem ecu seeing I’ve herd it’s a bit of a nightmare to get the over complicated a/c setup to work

    Ps all ways enjoyable content thanks tuning fork

  • Reply ARavenousChimp April 6, 2018 at 10:53 am

    If I were to run a piggyback ECU on a USDM 2012 STi, would it leave enough of the factory stuff in place that it would pass an OBD2 readiness test?

  • Reply 64nine April 6, 2018 at 12:01 pm

    What should i do for my v8td 79 series… reflash.. unichip or is there a haltech model that suits??

  • Reply amadafaka April 6, 2018 at 12:53 pm

    I am glad they answered the piggy back question. I was curious to know if I can keep the factory ecu for abs and airbags and a haltech for an engine swap.

  • Reply Ian Bennett April 6, 2018 at 1:19 pm

    Great Q&A… helpful and solid, and a great reason to go Haltech!

  • Reply sk8te-penguin April 6, 2018 at 1:30 pm

    My engine runs variable valve timing (Ford sigma 1.7 "zetec") and I want to add a turbo, but I also want to keep the standard dash and instrument cluster for rpm, speed etc. What ecu and install would you recommend and how would it control the valve timing?

  • Reply kispuss April 6, 2018 at 9:15 pm

    It would be verry nice with a "how To" video on a piggyback installation.. n/a to boosted on at newer car. Using the onboard map sensor on the haltech…. Whats going to happen with the factory ecu and its map sensor when suddenly reading boost.
    And same situation if the car had maf sensor. Thats one of my main concerns when considering boosting my 2015 car, where i se piggybacking as my only option.
    love your videos!!
    Cheers fro Denmark

  • Reply kel Robins April 6, 2018 at 11:09 pm

    Gday I have an interceptor that I want to remove from a vs v6 commodore will the factory ecu work as per normal after removal do I have to reset anything on ecu before I remove THANKS

  • Reply Augusto Pinochet April 7, 2018 at 12:50 am

    Is it possible with a haltech ECU to have multiple Tunes that are easily selectable say 1 for emissions one for performance and one for maximum fuel economy

  • Reply 2s2bs April 7, 2018 at 4:29 am

    Are Australians crazy about Diesel? What about Diesel tuning? I am not sure if I ever came across it or saw a passion for it from you guys. How does Diesel tuning work?

  • Reply Petey [email protected] April 7, 2018 at 7:25 am

    Hey Scott, what would be the easiest way to to make my 3rz hilux tunable for a turbo conversion?

  • Reply Aussie Aus Deutschland April 7, 2018 at 2:04 pm

    I've noticed that you do plug in ECU's for say Nissans ect that run everything including all the dash gauges. Im wondering if you are looking at doing a direct plug in to the E Series Falcons?

  • Reply MoPower April 8, 2018 at 3:20 am

    how do you wire in and signal electric fans to turn on with the elite

  • Reply BMW 325 GTE April 8, 2018 at 10:54 pm

    Can you display different traction control setups on the IQ3 for example 20%, 15%, 10%, Dry and WET slip

  • Reply The Rx7 roadie BURPLE RX7 April 9, 2018 at 7:06 pm

    I have a Rx7 fd road car, I have the ps1000 Ecu and iq3 street dash and I was contemplating getting the racepak smartwire system.
    Only trouble is I fear the smartwire won’t have enough channels for all the necessary functions of a road car. Also I can’t find any guides for fitting,

    Would it be possible to run smartwire and install while getting rid of the 3 or 4 fuse boxes the car has and maintain all the functions the car needs to operate on the 16 or so channels the smartwire has

  • Reply PredaGator April 12, 2018 at 7:44 am

    so a piggy back would be the way to go for a cl9 accord euro as honda has done some funny stuff with the ecu dbw and immobiliser

  • Reply C LK April 15, 2018 at 5:02 pm

    Hey bro. How to do the Boost By Gear setup? I tried to do the gear calibration and it only went to 0. Help plz.i have an elite 1500,SR20VE fwd

  • Reply 2slofouru April 20, 2018 at 1:46 am

    That boost by gear info was really helpful, thanks!

  • Reply Delano Williamson June 7, 2018 at 4:27 pm

    Hey there can a heltech ecu plug on to a BMW 335i 2014 ecu or the would be a lot of changes

  • Reply Ziyaad Ahmed December 2, 2018 at 1:29 am

    Which Would you guys recommend, a piggyback ecu chip(signal bender), or an ecu remap?

  • Reply Gringo! March 18, 2019 at 9:53 pm

    The second ecu install is called a parallel install.

  • Reply Chokky Leurov April 7, 2019 at 9:13 am

    What kind of piggy back ecu would you recommend for a supercharged 98 camry v6 auto? Im new to this lol

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