Hey guys, this thread is to debunk some myths about tuning and to explain the basic process for those who do not know what we do when we reprogram your vehicle.
This is a volumetric efficiency table. It maps the theoretical efficiency of the engine as a pumping device. Every formula the computer uses to calculate fuel and spark delivery starts with this data. You can add all the upgrades, intake, exhaust, boost, you want but you will not make more power at the wheels until this table has been adjusted to reflect your newfound efficiency increases. Any time you make ANY change to the engine's equipment the computer needs to be completely recalibrated. If you do not your engine will in fact run poorly compared to a fully stock setup.
This is a spark table. The factory sets these data points at a relatively conservative value that will work in all weather, load and fueling conditions. If you supply the engine quality fuel you can alter the ignition timing with this table and create more downward thrust on the pistons, making more power with the same amount of fuel. Equaling more MPG, fun and return on investment. There is no automatic calibration for spark tables, this takes trial and error, and precise measurement therefore they are ideally found using a dyno.
This is where the 87 vs 93 octane tunes come into play. If you have an 87 octane tune you can only run a little more timing than stock, if any. (Giving you only a little more power than stock, if any.) With a dedicated 93 octane fuel source, we can bump the timing up to support a higher level of power than you can safely run on regular gas. "Safely" is used because if the timing is advanced too far the pistons will begin to fight the rest of the crankshaft and will cause excessive wear and heat on your internal parts.
The maximum amount of power the engine is allowed to produce is hard coded into the computer. This factor will cap any attempts at performance without having been edited. This is one of the two types of torque limiting. The other applies to each shift, removing a slight amount of power depending on speed and throttle position. Many people wonder if this will affect the lifetime of their parts but the answer largely depends on how the vehicle is being driven. If gently used, your setup should last almost indefinitely - abuse tends to shorten that life no matter how much power the computer removes.
If an engine has had components removed from it for racing purposes, it takes one click to remove the error codes from the computer so that the system will run correctly and not enter failsafe mode.
We make sure that your wheel and tire combination is exactly recalibrated to real life measurement so that the transmission will shift perfectly no matter how much you change your rolling stock. This is again much easier to do in person as most "35 inch" tires etc are nowhere near 35 and measured height usually changes while in motion especially on the big trucks. We check and set this via GPS or on the dyno. Speed limiting can also be easily changed for racing.
Once all these variables have been set, the new file is uploaded to the vehicle computer and then tested. It only takes a few moments as if transferring files to a USB drive.
Engines that have been drastically changed from stock need drastically altered data tables so they take longer to set up and involve far more than explained here.
Dyno results are pretty typical for bone stock engines, a small bump in power along most of the curve. We haven't dyno'd any vehicles with a box tuner, if any we just delete them before we get started. As far as custom engines, every one is different and there are plenty of forums to see dyno sheets from every combination.
One thing we would like to make clear is that the dyno sheet is only a small part of how your vehicle will actually drive and feel. Almost every sheet you have probably ever seen was a WOT run, most driving is not WOT so you will experience different behavior than seen on a sheet. Some of the best mods for DRIVING don't make that much more power on the top end but give a ton more oomph from a stop or mid range at part throttle which is clearly visible when the VE table is being edited. Deleting torque management doesn't produce much more overall power but it does really also add to the "around town" low end you're actually looking for.
A dyno sheet on a properly calibrated engine pretty much reflects the VE table as mentioned before. Imagine cutting the 3D table 45 degrees through the middle and look at it from the side - that is basically your full throttle dyno curve. New equipment will give you extra bumps in either high end, low end or total volumetric efficiency / torque.
A word about dynos - Not all dynamometers are the same. Some use a loading method which essentially reproduces the load at the wheels the test vehicle would theoretically experience while driving in real life. This is the only way aside from actually driving the vehicle to determine the correct data for all calibration. There are other, cheaper dynos out there which are free wheel setups and do not load the vehicle so it is impossible to get part throttle part load calibration correct on those devices. The free wheel units also usually read a higher horsepower number at the top end as the engine is revving freely and not against the "weight" of the vehicle.
A word about accuracy - you can tune all you want but unless a HIGH QUALITY wideband O2 sensor is installed in the exhaust of the vehicle you will not be able to achieve a perfect tune. This tool is essential for boosted engines as the standard O2 sensors are not capable of reading accurately beyond the naturally aspirated stochiometric value of air:fuel (14.6:1). When operating with intake charge above atmospheric pressure, more fuel is required, pushing the ratio into ~10-11 territory.
A word about diesels - these basic principles apply but the tuning itself is different. The Duramax engines allow for very flexible electronic control and can add extremes of power quite easily. Enough power to break driveline parts, so we typically use a mild tune for diesel owners unless otherwise requested.
A word about in person tuning - When you come to us, or another competent tuner, the vehicle leaves perfectly adjusted - the end. This saves you time, money and risk in major amounts! Support your local tuner! Click here to find a local Mustang dyno shop.
Keep in mind everyone talks about how much horsepower their engine makes. This is silly because horsepower is usually max at top RPM and 1:1 gear ratio. In almost every vehicle making 300+ horse this maximum horsepower number is produced at speeds which are not only completely unsafe for most factory vehicles they are downright deadly when used on public roads.
This all sounds simple but the methodology and engineering behind these tables is highly advanced and only those with an intimate understanding of the mechanics, fluid dynamics and electronics of these systems can begin to properly calibrate them. Leave this to the professionals! Feel free to contact us with questions or to have your vehicle tuned!
*I wrote every word of this so let me know before you steal it. Thanks.
This is a volumetric efficiency table. It maps the theoretical efficiency of the engine as a pumping device. Every formula the computer uses to calculate fuel and spark delivery starts with this data. You can add all the upgrades, intake, exhaust, boost, you want but you will not make more power at the wheels until this table has been adjusted to reflect your newfound efficiency increases. Any time you make ANY change to the engine's equipment the computer needs to be completely recalibrated. If you do not your engine will in fact run poorly compared to a fully stock setup.
This is a spark table. The factory sets these data points at a relatively conservative value that will work in all weather, load and fueling conditions. If you supply the engine quality fuel you can alter the ignition timing with this table and create more downward thrust on the pistons, making more power with the same amount of fuel. Equaling more MPG, fun and return on investment. There is no automatic calibration for spark tables, this takes trial and error, and precise measurement therefore they are ideally found using a dyno.
This is where the 87 vs 93 octane tunes come into play. If you have an 87 octane tune you can only run a little more timing than stock, if any. (Giving you only a little more power than stock, if any.) With a dedicated 93 octane fuel source, we can bump the timing up to support a higher level of power than you can safely run on regular gas. "Safely" is used because if the timing is advanced too far the pistons will begin to fight the rest of the crankshaft and will cause excessive wear and heat on your internal parts.
The maximum amount of power the engine is allowed to produce is hard coded into the computer. This factor will cap any attempts at performance without having been edited. This is one of the two types of torque limiting. The other applies to each shift, removing a slight amount of power depending on speed and throttle position. Many people wonder if this will affect the lifetime of their parts but the answer largely depends on how the vehicle is being driven. If gently used, your setup should last almost indefinitely - abuse tends to shorten that life no matter how much power the computer removes.
If an engine has had components removed from it for racing purposes, it takes one click to remove the error codes from the computer so that the system will run correctly and not enter failsafe mode.
We make sure that your wheel and tire combination is exactly recalibrated to real life measurement so that the transmission will shift perfectly no matter how much you change your rolling stock. This is again much easier to do in person as most "35 inch" tires etc are nowhere near 35 and measured height usually changes while in motion especially on the big trucks. We check and set this via GPS or on the dyno. Speed limiting can also be easily changed for racing.
Once all these variables have been set, the new file is uploaded to the vehicle computer and then tested. It only takes a few moments as if transferring files to a USB drive.
Engines that have been drastically changed from stock need drastically altered data tables so they take longer to set up and involve far more than explained here.
Dyno results are pretty typical for bone stock engines, a small bump in power along most of the curve. We haven't dyno'd any vehicles with a box tuner, if any we just delete them before we get started. As far as custom engines, every one is different and there are plenty of forums to see dyno sheets from every combination.
One thing we would like to make clear is that the dyno sheet is only a small part of how your vehicle will actually drive and feel. Almost every sheet you have probably ever seen was a WOT run, most driving is not WOT so you will experience different behavior than seen on a sheet. Some of the best mods for DRIVING don't make that much more power on the top end but give a ton more oomph from a stop or mid range at part throttle which is clearly visible when the VE table is being edited. Deleting torque management doesn't produce much more overall power but it does really also add to the "around town" low end you're actually looking for.
A dyno sheet on a properly calibrated engine pretty much reflects the VE table as mentioned before. Imagine cutting the 3D table 45 degrees through the middle and look at it from the side - that is basically your full throttle dyno curve. New equipment will give you extra bumps in either high end, low end or total volumetric efficiency / torque.
A word about dynos - Not all dynamometers are the same. Some use a loading method which essentially reproduces the load at the wheels the test vehicle would theoretically experience while driving in real life. This is the only way aside from actually driving the vehicle to determine the correct data for all calibration. There are other, cheaper dynos out there which are free wheel setups and do not load the vehicle so it is impossible to get part throttle part load calibration correct on those devices. The free wheel units also usually read a higher horsepower number at the top end as the engine is revving freely and not against the "weight" of the vehicle.
A word about accuracy - you can tune all you want but unless a HIGH QUALITY wideband O2 sensor is installed in the exhaust of the vehicle you will not be able to achieve a perfect tune. This tool is essential for boosted engines as the standard O2 sensors are not capable of reading accurately beyond the naturally aspirated stochiometric value of air:fuel (14.6:1). When operating with intake charge above atmospheric pressure, more fuel is required, pushing the ratio into ~10-11 territory.
A word about diesels - these basic principles apply but the tuning itself is different. The Duramax engines allow for very flexible electronic control and can add extremes of power quite easily. Enough power to break driveline parts, so we typically use a mild tune for diesel owners unless otherwise requested.
A word about in person tuning - When you come to us, or another competent tuner, the vehicle leaves perfectly adjusted - the end. This saves you time, money and risk in major amounts! Support your local tuner! Click here to find a local Mustang dyno shop.
Keep in mind everyone talks about how much horsepower their engine makes. This is silly because horsepower is usually max at top RPM and 1:1 gear ratio. In almost every vehicle making 300+ horse this maximum horsepower number is produced at speeds which are not only completely unsafe for most factory vehicles they are downright deadly when used on public roads.
This all sounds simple but the methodology and engineering behind these tables is highly advanced and only those with an intimate understanding of the mechanics, fluid dynamics and electronics of these systems can begin to properly calibrate them. Leave this to the professionals! Feel free to contact us with questions or to have your vehicle tuned!
*I wrote every word of this so let me know before you steal it. Thanks.
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