Tune Check List
You need to make sure you are tuning a healthy engine.
We suggest you complete a compression test prior to your tuning appointment. If you would like us to perform a compression test, please contact us PRIOR to the tuning appointment.
Typical compression test results should be as follows:
8:1-8.5:1 compression: 150-170 psi per cylinder
8.5:1~9.5:1 compression: 170-210 psi per cylinder
9.5:1~11:1 compression: 210-275 psi per cylinder
11:1+ compression: 250+ per cylinder (highly depends on cams being used)
These pressure values will be less at higher elevations. Compression Tests should be performed on a warm engine and the throttle should be held fully open while testing. YOU SHOULD NOT have more than 20psi variance between cylinders. If you have one cylinder that is showing a greater variance than 20psi then you will need to repair that problem prior to your dyno tuning appointment. The additional cylinder pressure realized after a custom tune will only exploit the existing mechanical problem causing further and usually more severe engine failure.
Cylinder Leakdown Tests:
- A Cylinder Leakdown Tests can also be performed on a warm engine.
- YOU SHOULD NOT have a cylinder leakage of more than 7% in any cylinder. If you do, then you will need to further test to see where the air is leaking from and to; intake valve seat, exhaust valve seat, head gasket, piston rings, etc.
- Please know that even if these test results look good, you can still have an engine that has some mechanical damage and the tuner/calibrator should be able to recognize the systems and consult with you about the consequences of further tuning your engine.
If you would like us to perform a cylinder leakdown test, please contact us PRIOR to the tuning appointment.
2nd = MAF, Turbo, Vacuum Lines, & Intercooler Systems:
- Make sure that your intake, vacuum lines, and intercooler piping are sealed when under vacuum andsealed when pressurized like when running full boost. This is super critical especially if the vehicle is using a MASS AIR FLOW sensor to meter air. A vacuum leak after the MAF sensor, but prior to the turbo will make the engine run leaner. A boost leak after the turbo, but before the engine will make the engine run richer. Major leaks can usually be found while dynotuning because the data will look incorrect, but minor leaks are very difficult to find so please pressure test these parts of your intercooler system. If you would like us to perform a boost leak test prior to the tuning appointment, please contact us to do so.
- Make sure you have secured all of your vacuum lines and your intercooler piping so they do not blow off at the tuning appointment.
- Make sure all of the bolts are tightened, in particular, the exhaust system bolts. An exhaust leak prior to the turbo will lose power and make part throttle tuning almost impossible. It will also create an increased amount of turbo lag.
- Make sure the blow off valve is properly lubricated, seals tight, and is functioning properly.
- Be sure to use the proper oil feed and return lines and that they are installed properly.
- Turbo shaft play. You cannot expect a turbo to operate properly if has worn excessively, have the turbo rebuilt or buy a new one.
3rd = General Pre-Tuning Maintenance:
- Make sure all fluid levels are up to par; this includes engine oil, anti-freeze, transmission fluid, differential/transfer case fluid, brake fluid, clutch hydraulic fluid, etc.
- Alignment and wheel balancing, the vehicle must be able to drive straight if it is to be tuned on a chassis dyno. We drive each vehicle we tune on the street after the dyno tune to verify proper operation. We should feel safe riding in your car after the tune.
- Bleed the coolant system before you come for the appointment. If your engine has an overheating problem, DO NOT come for the appointment. Because we cannot tune a car that is overheating.
- Check for leaks. A car leaking oil, coolant, tranny fluid, transfer case fluid, etc. may be turned away before the tuning appointment. The chassis dyno is a very expensive tuning tool and we would appreciate if your vehicle did not leak all over it during the appointment.
- The vehicle must be streetable and the driveline and drivetrain systems must be in tact and safe, if you have any clicking CV joints then repair them prior to the tuning appointment. Be sure to inspect your wheel bearings as well. The same stresses that your vehicles sees on the street are seen on the chassis dyno, although a failure on the chassis dyno puts your vehicle and the tuner/calibrator in a very unsafe environment until the vehicle and chassis dyno come to a complete stop.
- Inspect and replace your fuel filter (if need be), any blockage in fuel flow to the engine will cause pre-mature fuel pump wear and can lead to engine damage if the fuel filter clog causes a lean burn condition. Make sure that you have the proper fuel octane and enough fuel to complete the tune. If you want a tune for race gas, E85, etc. we suggest you let us know prior to the tuning appointment so we have the adequate fuel for the appointment if you don’t provide it yourself. Fuel Pumps, you should not have installed the fuel pump if you see dirt, debris, or rust in the tank. If there is rust in the tank, replace the fuel tank. You will starve the engine of fuel if you leave junk in the fuel tank.
- If your engine oil and filter have been run for more than 3,000 miles, please replace the filter and your engine oil.
- If your spark plugs (& wires) have more than 5,000 miles on them (if they are copper plugs) or 15,000 miles on them (if they are iridium/platinum), please replace them with new ones. Be sure to gap them appropriately and to use a small amount of anti-seize when installing the new spark plugs. Bring extra spark plugs, during tuning it is possible to foul the plugs to a point where they will need to be replaced. New spark plugs are NOT included in the tuning rate. If you would like us to supply the spark plugs, please contact us prior to the tuning appointment. We stock many different style and heat range plugs already so we may have what you need, but please check before coming to the appointment.
- Make sure you have appropriately functioning brakes on the vehicle that are suited for your power level. We drive each vehicle we tune on the street after the dyno tune to verify proper operation. We should feel safe riding in your car after the tune.
If your injectors are over 5 years old:
We highly suggest you remove them and have them cleaned and calibrated by an injector cleaning facility like:
Additional Important Info:
- If you have one poorly flowing fuel injector, then it is possible to further damage your engine by completing a dyno tune. This is because the tuner/calibrator is only metering the Lambda (Air/Fuel Ratio) from one location the assumption is that all fuel injectors are flowing the same rate.
- If your vehicle is over 5 years old or is driven in a humid oceanic environment, we suggest you clean your engine grounds and grounding attachment points. A vehicles electrical signals need to be as clean as possible so the ECM has good signals coming in and going out. The engine harness should have no exposed wires. Also, do no twist and tape wires together. Take the time to properly crimp or solder them together!
- Battery/Alternator – Make sure these items are strong and operating properly.
- Check Engine Lights or Codes – Do not come for a tuning appointment if you have a check engine light on. Please have this problem diagnosed and fixed prior to your appointment, or we can do this prior to the tune with your permission.
- A tuner/calibrator’s job is to develop a tuned calibration specific to your vehicle, not fix everything that is wrong with it. If you come to an appointment with a car that is not in proper working order you may be asked to leave depending upon the severity of the issue. If the problem is minor and can be easily fixed at the shop during normal operating hours, then we can fix it, but NOT FOR FREE.
Dyno tuning time starts when the vehicle is driven into the chassis dyno cell so our goal is to make this time as effective as possible in order to make the cost to the client as little as possible.