Frequently Asked Technical Questions

Historically, the quickest and fastest ATS-Vs have all launched between 3 and 6 pounds of boost, on drag radials or slicks. Don’t fall for the marketing hype from some tuners and believe that a ‘full boost launch’ is going to make your car any faster or more fun to drive. At least not with a stock torque converter that has stall and flash speeds between 2,500 to 3,000 rpm. However, this will all be changing soon now that we’ve introduced a higher stall torque converter. Imagine a properly engineered torque converter that allows you to sit at the starting line between 3,500 and 4,000 rpm. This will produce much more boost, and rocket launches.

We can program for this if you’d like. However, all Tapout tunes retain factory idle quality and drivability. For this reason, nearly all of our customers opt for power increases in all driving modes.

Yes, of course. Our tunes include a complete restructuring of the low pressure fuel pump (LPFP) strategy, including desired high flow base commanded pressure, high flow upper mode and high flow lower mode table reworks. These edits serve to provide increased volume to the high pressure fuel pump (HPFP), allowing it to maintain full pressure at higher boost, under increased load and for longer periods of time. We also adjust the HPFP desired pressure table for maximum performance.

No way. We maintain OEM Knock Retard operation and knock sensor sensitivity settings for all cylinders. This allows the ECM to reduce ignition timing in case of bad fuel, low octane, or other conditions where ignition timing is excessive. Some tuners completely disable Knock Retard, and this can cause catastrophic engine failure. If you have a tune from someone else and never see any knock retard in your scans, beware!

Yes, even the factory tune includes bi-directional knock retard and six zone functionality. We maintain those settings and go much farther. Most burst (predicted) knock retard learning is disabled in order to keep false knock under control. Additionally, when real knock is detected and the ECM retards ignition timing advance via knock retard, we allow the timing to return much faster (in the absence of further knock) due to increased knock retard recovery rates.

We maintain OEM fuel trim learning functionality. This will allow your ECM to use feedback from the stock narrow band oxygen sensors to automatically adjust idle, cruise and part throttle air/fuel ratio for different atmospheric conditions, brands of fuel, etc. And this is one of the reasons our tunes idle and cruise just as smoothly as stock. Leaving fuel trim learning enabled will also allow the ECM to set a CHECK ENGINE light if something is wrong with your air/fuel ratio. In fact, we set tighter limits than the factory, using boundaries in the 15 to 20% range instead of 35 to 40%. Some tuners disable fuel trim learning to mask improperly tuned mass airflow (MAF) tables.

We leave all Diagnostic Trouble Codes (DTCs) fully functional, except ones related to catalytic converters in cases where catless downpipes have been installed. This allows your CHECK ENGINE light to illuminate and make you aware of any engine, transmission and/or sensor problems. Some tuners disable specific DTCs so customers won’t see a CHECK ENGINE light when there is inherent tune problem.

We specifically leave DTC P228C enabled in all our tunes. This allows the ECM to switch to Reduced Engine Power mode in cases where fuel rail pressure is less than desired for an extended period of time, and could potentially save your engine.

We can set the electronic throttle to automatically close in case of excess boost. This is recommended for anyone who really wants to push the limits with tuning. However, during normal operation, our tunes allow the electronic throttle to remain 100% open under load.

We can set the electronic throttle to automatically close in case of excessive post intercooler temperature (typically in the range of 150 to 160° Fahrenheit). This can be used as an intercooler failure ‘circuit breaker’, and is also useful in hotter regions with drivers who thrash their cars exceptionally hard (i.e. half or standing mile racing, and/or repeated high speed floggings). If you heat soak your car at the drag strip for example, these settings will temporarily reduce boost to keep your engine safe.

• A completely stock ATS- V will typically produce 425 to 435 whp.
• An ATS-V with good aftermarket tune should produce 475 to 490 whp.
• An ATS-V with intake, exhaust, spark plugs and tune can produce 500 to 525 whp.
• An ATS-V with intake, exhaust, spark plugs, methanol injection/ethanol fuel blends and tune might make anywhere from 535 to 600 whp, depending on how much methanol you spray and how much risk you’re willing to take.

All the above whp numbers assume you’re using a DynoJet dyno with SAE correction factor and smoothing parameter set to 5.

ECM = engine control module (2016 through 2019 ATS-V engine settings) TCM = transmission control module (2016 through 2019 ATS-V A8 automatic transmission settings) CCM = chassis control module (2017 through 2019 ATS-V active exhaust settings) Each of these takes a different number of credits to tune. Refer to our credit chart to see the right amount.

The E78 controller was introduced in 2011 and used a new torque based control structure. To get an idea how this system functions, take a look at the following report from HP Tuners. HP Tuners How to tune the E78 and E39 ECM

Yes. We spend countless hours on the dyno studying the hundreds of calibration tables found in the LF4 ECM calibration. We dig deeper than others and often uncover hidden tables that others do not have knowledge or and/or access to. We lock all tunes in order to protect our intellectual property. Our calibration files may only be viewed and/or edited by Tapout Tuning, L.L.C.

HP Tuners MPVI2 / VCM Suite includes two Universal Credits when purchased from us. You will need two credits to license your 2016 ATS-V or four if you have a 2017, 2018 or 2019 ATS-V. We will also need to license your vehicle in order to write your calibration. Our cost for acquiring these credits is included in the Tuning prices. For a complete list of how many credits are required for your year and control module check our table.

HP Tuners VCM Suite has been designed to work with Microsoft Windows® 7 or newer. Windows® 10 is the recommended operating system. Minimum system requirements:

• 2 GHz CPU
• 4 GB RAM
• Microsoft Windows® 7 or newer
• Microsoft .NET Framework 4.6.1 or higher
• USB Port

Of course. We start with a scan of how your car is currently working with the parts and mods that are already on your car. Then we create a custom calibration specifically for your car. In fact, if make additional modes mods within 30 days of our tune we will retune and optimize it for free.

It depends. For cars that are still running catalytic converters, emissions testing should be no problem. For cars with the cats removed, our tune won’t keep you from passing an emissions test, but your lack of cats will.

The OEM LF4 turbochargers are Mitsubishi TD04L6 models with 20TK3S compressor wheel. These units can effectively support 275 to 340 crankshaft horsepower per turbo, which works out to approximately 600 whp on the dyno. They just can’t move more air than that, so realistically there’s no more power to be made.

2016 ATS-V uses E92 ECM. 2017 through 2019 use E92A. E92 was used in many 2014 through 2017 SIDI engines. E92A is GM’s premium direct injection ECM. Tapout Tuning can tune the following control modules: ECM = engine control module (2016 through 2019 ATS-V engine settings) TCM = transmission control module (2016 through 2019 ATS-V A8 automatic transmission settings) CCM = chassis control module (2017 through 2019 ATS-V active exhaust settings)

Stock LF4 spark plugs are AC Delco 41-147, 12662396, iridium, gapped between .030 and .035″. Most people tuned for higher boost are running one or two heat ranges colder than stock, gapped a little tighter. We recommend NGK 6510 gapped at .027″. Below is an image showing three spark plugs for our engines. On the left is the OEM AC plug, in the middle is the Denso and on the right is the NGK. The AC and NGK plugs both use projected tips, while the Denso does not. Some people believe the non-projected tip design is better for boosted applications, since it doesn't hold as much heat down in the combustion chamber. We have personally run both brands and tested both plug designs on the dyno. We found them to be within one percent of each other in terms of measurable performance. This is within the margin of error of the dyno itself, so this is a wash in our opinion. Since there was no quantifiable performance improvement with the Denso design, we made the decision to return to OEM style plugs, in a colder heat range. That's why Tapout Tuning runs, stocks and recommends NGK spark plugs for the LF4 engine. When you replace the spark plugs, always apply dielectric grease on the inside of the coil pack connector boots. This will displace the air and prevent carbon tracking. You can buy them here

• 13 to 15 psi is stock for lower altitudes. Those at higher elevations will likely see less.
• 17 to 20 psi is what you can expect with most aftermarket tunes.
• 18 to 20 psi can be run with intake, exhaust, spark plugs and tune.
• 18 to 23 psi may be run with intake, exhaust, spark plugs, and methanol injection or ethanol fuel blends. That’s the practical limit for stock LF4 turbochargers.

Generally speaking, it’s realistic with proper tuning to add approximately 15 to 20 whp for each additional pound of boost on these engines.

If you’re using a sniffer and going to put the wideband sensor in one of the tailpipes, use an inner one with the exhaust valves open. You can also install your wideband in place of one of the rear narrow band sensors if you are running catless downpipes and already have the related rear oxygen sensor DTCs disabled in your tune. The best solution of all is to have an exhaust shop weld an additional bung in place for the wideband.

Yes. You will actually have cooler exhaust gas temperatures while running water/methanol injection. This is because the water draws heat out and the methanol burns cooler than gasoline.

If you have run your car in the eighth mile and want to know how it will perform in the quarter mile, simply multiply your time by 1.555. All the ATS-V time slips we have data for show a ratio between 1.530 and 1.560. Ratios on the lower end of that range normally indicate a front half problem such as starting line traction or a missed 1-2 or 2-3 shift in the case of a manual transmission. Ratios on the upper end of that range tend to imply a back half problem such as knock retard, boost drop-off or a missed 3-4 shift in the case on an M6 car.