Frequently Asked Technical Questions for ATS-V

The factory ATS-V fuel system is designed to safely accommodate ethanol blends up to E10. With proper fuel system modifications (i.e. LPFP and fuel cam, or methanol injection, plus wideband oxygen sensor), we can get you a beautiful flex fuel tune that will support E0 to E55.

it depends on how much boost you are targeting and how high of ethanol content you would like to run. Some people claim that you can run E30 on the stock fuel system. However, this is a dangerous and misleading statement. We have repaired and/or replaced many engines for people who trusted that negligent advice. Although the stock fuel system can technically handle E30, you will be required to reduce boost down to the point that you won't make any more power than you could have on pump gas. With our Stage 1 LPFP, fuel cam and alcohol content sensor you can typically run ~ E47 without issue. This is convenient mix of half pump gas and half pump E85. If you add on the AutoTech HPFP internals, you can run up to straight E85 at reasonable boost levels. With the stock or Turbobay turbos turned all the way up on a Kill Tune, you should be safe somewhere in the E60 to E70 range. For those stepping up to Caddy Issues turbos, you will need to upgrade to the Stage 2 OG Solutions LPFP, and/or add methanol injection

On 2017 and later GM cars, tuners can only tune the ECM, which controls the engine settings. In order to tune the TCM, which controls the transmission settings, you need to send yours out for unlocking, or purchased an unlocked one. This costs $350 to $400 plus shipping. Then you’ll need to spend another $200 in license credits from HP Tuners. Having the ability to tune the TCM will allow us to change shift points, shift feel and firmness.

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.

The stock tune will remember if you leave the car in Touring or Sport mode. However, it will not remember Winter or Track modes. Our tune behaves in the same manner.

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.

Tapout tune drivability is at the same level as OEM or better, so we don’t really see any logic in having one mode with less power than the others. To us that seems like a ‘feature’ that provides no benefits.

No. And the one company that markets this feature doesn’t have it either. Check out this article for the facts: Here

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 with A8 transmission will typically produce 425 to 435 whp on 93-octane. M6 cars are about two percent higher. 91 and 92 octane cars will be lower.
• An ATS-V with proper aftermarket tune should produce 475 to 500 whp.
• An ATS-V with exhaust, spark plugs and wideband tune can produce 500 to 525 whp.
• An ATS-V with 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.

When you purchase our tune, we typically cover any and edits you may want or need for the first 30 days. After that, you can sign up for any of our monthly tuning subscriptions if you still want to continue with tuning edits. This would cover things like new mods, different octane fuels, race track specific tunes, remote dyno tuning, etc. Any of these subscriptions may be cancelled at any time, but many customers enjoy having me at their beck and call 365 days per year.

Yes, we can add burble/crackle to your tune. However, this is not safe for your OEM catalytic converters. Once you upgrade to catless downpipes, it should be safe to move in this direction if this is your sort of thing.

Our preference is to always tune these cars when they're stock, before any modifications are installed. This gives us the opportunity to find and fix pre-existing problems. Then we can update the tune each time you add new mods. If you just start installing mods and there is a problem, it's sometimes tough to tell whether it was a pre-existing problem with the car, an installation issue or a tuning error. We're then forced to try to solve an equation with three variables.

The stock tune will remember if you leave the car in Tour or Sport mode. However, it will not remember Snow/Ice or Track modes. Tapout tunes add settings outside of HP Tuners for driving mode non-volatility. This means the ECM will now automatically remember the driving mode between ignition cycles. This includes Tour, Sport, Snow/Ice and Track, in addition to Auto Rev Matching for M6 cars. This is pretty much a Tapout exclusive. No other HP Tuners based tuner has access to all these tables.

On LF4 engines, the right/passenger side bank is the farthest forward. That's what makes the right side of the engine 'bank 1'. The right front cylinder, closest to the coolant bottle, is cylinder one (1). On the right/passenger side, the cylinders are numbered 1-3-5, from front to rear. On the left/driver side they are numbered 2-4-6.

We run any brand of 5W30 synthetic for all 'normal' street cars. In hotter climates like Florida, Texas and southern California we recommend 5W40. Above 700 whp, we recommend 5W50 racing oil with lots of zinc.

• Engine oil: ACDelco dexos1 full synthetic, 5w30 (7.0 quarts with filter)
• Engine coolant: 50/50 mixture of DEX-COOL with clean drinkable water (12.3 quarts for engine, plus 3.3 quarts for intercooler)
• Mobil 1 Synthetic LV ATF HP transmission fluid, GM part number 19417577 and its blue colored label. Do not use the black bottles or grey labeled HP fluids as those contain earlier formulations that cause TCC shudder in some cases.
• M6 manual transmission fluid: manual transmission fluid, GM part number 88861800, 88861801 in Canada
• Rear axle and limited slip differential (driver’s side): DEXRON LS gear, 75w90, GM part number 88862624, 88862625 in Canada (1.6 quarts)
• Electronic limited slip differential (passenger’s side): DEXRON-VI automatic transmission fluid (0.149 quart)
• Hydraulic brake and clutch system: DOT 3 hydraulic brake fluid

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 Brisk Silver Racing Plugs that come pre-gapped. When you replace the spark plugs, always apply dielectric grease (included with our Brisk plugs) on the inside of the coil pack connector boots. This will displace the air and prevent carbon tracking. Recommended torque value when installing in aluminum cylinder heads is 8 to 14 foot-pounds. 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.

21 to 26 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.

25 to 30 psi is possible with our Caddy Issues turbochargers.

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

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.

With the OEM hoses, it’s extremely difficult to determine how well fluid is flowing and whether air might still be present in the system. In this video I shortened up one of the factory hoses, then added a ¾” barb coupler, short piece of UV-resistant clear PVC tubing and two hose clamps. This step is not mandatory, but now that it’s done, I definitely wish I had done it a year ago. To fill and bleed the intercooler system, you do not want to leave the pump running. Most of the air bubbles come to the surface when the pump starts and stops. For this reason, starting and stopping the pump every few seconds will yield much better results than leaving it running continuously. There is a positive battery terminal right beside the fuse box in the engine compartment. Use a jumper wire to carefully short between the battery terminal and either side of the intercooler pump fuse. This video shows a 2018 ATS-V, but the fuse location may vary in other years. Check the underside of the fusebox lid in your own car to identify the proper fuse. Rotate your intercooler fill port to the vertical position. Remove the rubber cap. Use a short piece of ¾” heater hose to support a large funnel. Add 50/50 coolant mix to the funnel. Depress the Schrader valve with a dowel rod or long ¼” extension. Continue cycling the intercooler pump power every few seconds until there are no more air bubbles. Sometimes it helps to fiddle with the 7 mm. bleeder screws, but this does not seem to be necessary. Through experience I have found it’s best to fill and bleed the system cold, the drive around until it’s up to normal operating temperature, let it cool down and bleed it one more time.

The stock intercooler works very well when the it is properly filled and bled. We always check intercooler performance before adding boost on every car we tune. We have found that approximately 25% of ATS-Vs have a completely non-functional intercooler, and another 25% have intercoolers that seem to work fine at stock boost levels but need bled and filled in order to keep up with higher boost levels. Our intercoolers only hold 3.3 quarts of fluid. If they're more than a few ounces low, an air pocket can reach the pump. When this occurs, the pump will turn off after five seconds, on order to protect itself. When the pump is off, manifold air temperature (MAT) skyrockets under boost. The ECM will respond by reducing target boost, pulling ignition timing advance and closing the throttle. Fortunately, there is a simple and inexpensive to make sure your intercooler is topped off and function fine. The Tapout ATS-V Intercooler Fill/Bleed Kit.

People ship cars to us from all over the country, so we have probably seen more LF4 connecting rod bearing failures than anyone. We believe there are several causes for this. When a fuel injector sticks open and pours fuel into the engine, the piston rings cannot prevent fuel from contaminating the engine oil. This will destroy bearings pretty quickly. Coolant intermix can also destroy engine bearings. So can beating on the car and not changing your oil once it loses it’s lubricating properties. For example, we recently took in a 640 whp car running ethanol with only 8% oil life remaining and all the bearings were destroyed. Some tuners elect to disable knock sensors and command excessive ignition timing advance. That is a recipe for disaster for many engine components, causing melted spark plugs, chipped valves and engine bearing failures. If you get past all those ‘user errors’, it can definitely be a challenge to keep bearings alive above 700 whp. However, we have now built more than one dozen LF4 engines making more than 700 whp. So we have the experience and knowledge to know what is necessary to keep the bearings alive. By the way, the OEM LF4 engine bearings are excellent quality and they’re even coated.

They don’t. All properly designed cold air intake systems will show balanced MAF readings from side to side. Equal length intake runners before the turbos is completely unnecessary.

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.

If you're on a stock tune with 91 or 92 octane, or otherwise poor fuel, you will likely notice a mild performance improvement with octane booster. If you're on 93 to 95 octane, it's just a waste of money. If you’re specifically tuned for it, octane booster can make a nice improvement in the performance of your ATS-V.

According to the BOOSTane™ website, there are a lot of additives that make claims about what they can do for your performance. However, BOOSTane™ is not your average octane boosting product. Utilizing a proprietary, patent pending blend, BOOSTane™ Professional effectively raises your fuel octane as much as 23 points, up to 116, if you want! We took a 2018 ATS-V A8 with intake, spark plugs, exhaust and tune and filled the tank with 93-octane Sunoco fuel before strapping down on our local dyno. Baseline was a solid 499 whp using SAE correction factor and smoothing = 5. We performed all pulls in sixth gear with the torque converter locked up to ensure we gathered the best possible data. This method shows the lowest numbers, but we prefer it since it’s the most reliable, consistent and repeatable from dyno to dyno. One 32 ounce can of BOOSTane™ Professional was poured into the tank. Based off of the BOOSTane Mixing Chart , the resulting octane was around 102. We were able to add a few minor tuning edits due to this higher octane and the result was 521 whp. We then added a second can to the tank (resulting in an octane of 104), made a couple more tweaks and found ourselves at 549 whp. Peak boost remained the same at 20 psi. Ignition timing advance was increased from ~ 8 to ~ 13° BTDC on the top end. Net gains were an astonishing 50 whp at the top of the powerband with solid gains throughout. Also notice that the power delivery became noticeably smoother with the increased fuel octane.

Yes. In today’s world, Cadillac dealerships are required to perform an ECM (ECM) scan before any powertrain warranty will be honored by General Motors and this is why Tapout is careful to leave all the OEM safeguards in place including fuel trim learning, knock retard learning and boost reduction in case of intercooler failure. In order to be reimbursed for warranty work, the dealerships will need to send the logs in proving this scan was completed and the ECM has not been unlocked. All custom ECM and TCM tuning can be detected by Cadillac dealerships, and will immediately void your powertrain warranty. For this reason, it’s prudent to assume that any future powertrain repairs after your custom tune will be out of pocket expenses.

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 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 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 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.

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 you make additional 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.

Different people have different opinions on this. You will find that some Mustang dynos read similar to DynoJets, and others get nicknames like 'heartbreaker'. We don't use Mustang dynos for this reason. The inconsistency makes the numbers have very little meaning to us. That said, any brand of dyno can be a good tuning tool, as long as you use the same dyno and same settings each time. We are aware of three main reasons why Mustang dynos tend to vary so much. First, these dynos require annual calibration, but that's expensive and therefore often gets skipped. Second, the correction factor does not need to be displayed on the dyno chart, making it easy for the operator to artificially inflate the numbers. And third, Mustang dynos can be cheated by changing the internal parasitics file. This file holds the inertial information for each dyno specific model. The parasitics are different across their product line since they use different size rollers, etc. for different models. By cheating this file, a dyno operator can basically make your chart show any number he wants. If you must use a Mustang dyno, our opinion is that you should at a minimum request SAE correction factor, and use the same dyno that you ran your baseline on.