Dyno day preparation checklist

This checklist should help you prepare for your upcoming dyno day, the list items may seem obvious but you'd be surprised at what gets forgotten in the mad rush to get the car prepared on the day before the remapping session!

On the car

Wheels and Tyres

• Check wheels for cracks/damage
• Check your tyres for cracking/damage - a tyre explosion on the dyno can cause some serious damage - it is most likely that the dyno operator will turn you away with poor condition tyres.
• Check the tread depth and make sure that your driven axle(s) have decent quality tyres on them at a minimum - rubbish tyres will likely slip on the dyno which will affect your runs.
• Check that your tyres are inflated to the correct pressure
• Torque wheel bolts/nuts to manufacturer specified values

Cooling system

Fluid leaks are a common reason for vehicles being denied entry to a dyno cell, so it pays to check the cooling system properly in advance.

• Check thermostat function - a sticky thermostat is likely to cause a premature end to any remapping session or dyno runs
• Check coolant level and top up where necessary
• Check coolant overflow/reservoir seal
• Check radiator cap seal (Where a cap is fitted)
• Check radiator drain plug for leaks
• Examine coolant hoses for leaks, particularly focussing on areas where pipes join other components, a white crusty water mark or slimey residue is usually a good indicator

Belts/chains

• Where possible examine timing belt/timing chain condition, your vehicle will experience greater than average loads whilst on the dyno and you certainly don't want these to give out
• Check auxiliary belts for wear and replace where necessary
• Check the condition of chain/belt tensioners and adjust or replace as necessary

Intake system

• Check the condition of your air filter, and dependent on the type either wash and re-oil or replace the filter element if required - these parts are exceptionally cheap so there is no real reason to not do this - a caked up air filter is only going to restrict airflow
• If your vehicle is equipped with a MAF sensor, clean it with either electrical contact cleaner, or products sold specifically as MAF cleaner (they are almost identical products)
• Check the general condition of intake hoses and replace any perished or damaged items
• Check joints between intake hoses for leaks and tighten/seal as appropriate

Turbocharged vehicles

• Test the function of blow off/recirculation valve - nothing should be escaping from it at idle
• Remove main intake hose and check impeller wheel for play, minute amounts of play are OK, but the wheel should not be able to contact the sides of the housing, nor should it be able to slide backwards and forwards on the shaft - also examine the fins for damage
• Check intake hoses for oil filming - the EGR system if active will deposit some oil into the intake, but excessive amounts could suggest seal or bearing failure on the turbocharger
• Ensure that the air hoses on the compressor side are securely clamped into place

Supercharged vehicles

• Ensure that the air intake hose is securely clamped onto the supercharger
• Check the condition of the belt and pulley and replace if necessary
• If you are going to be running more boost, now is the time to fit that underdrive pulley
• Now would be a good time to service your supercharger if it hasn't been done recently

Intercooler

• If your vehicle is equipped with an intercooler, visually inspect it for damage and hoover the debris and road grime from it being careful not to damage it in the process - some bent fins are usually fine but if there are visible holes then you'll need to replace this before remapping

Exhaust system

• Check exhaust manifold studs and nuts, making sure they are torqued to spec
• Check downpipe joints and flexis for broken gaskets/exhaust leaks, these will usually have a layer of soot emanating from the source of the leak, replace gaskets if necessary
• Install decat pipe if this is to be part of your tuned spec, check for leaks at joints
• Examine centre pipe for damage/leaks, repair/replace as appropriate, check for leaks at joints and replace gaskets as required
• Examine silencers and the rest of the rear pipe(s) for leaks, the welded joint between the rear pipe and the silencer is usually where you'd see splits/leaks

Turbocharged vehicles

• Check torque on turbo to manifold bolts/studs and nuts
• With the downpipe removed, check the exhaust wheel for play, minute amounts of play are OK, but the wheel should not be able to contact the sides of the housing, nor should it be able to slide backwards and forwards on the shaft - also examine the fins for damage
• Check the gasket and stud/nut torque or vband(s) on the connection between the turbo exhaust housing and downpipe
• If your vehicle is equipped with an internal wastegate, check that it moves freely
• If your vehicle is equipped with an external wastegate check the condition of the wastegate spring and check for exhaust leaks around the vband clamps

Oil and filter/general service items

• Check for oil leaks under the car, you'll be denied entry to the dyno cell if your car is leaking all over the floor!
• If your vehicle hasn't been serviced recently, now would be a good time to change the oil and oil filter
• Similarly, if it hasn't been changed recently, change the fuel filter

Drivetrain

• Check shift mechanism functions correctly and that you can select all gears
• On manual vehicles check operation of clutch master and slave cylinders, check for leaks
• On manual vehicles ensure that the clutch is not slipping
• Ensure gearknob is properly attached
• Check gearbox oil level and top up as appropriate - if the fluid and filter are old, consider changing them
• Check driveshafts for play, repair or replace as appropriate
• Check diff oil level and top up as appropriate
• If vehicle is 4WD, AWD or RWD check propshaft couplings and universal joints for play, repair or replace as appropriate

Brakes

• Ensure none of the brake calipers are binding
• Ensure that handbrake shoes are not binding
• Check condition of brake hoses to ensure none are leaking

Diagnostic Scan

• Run a diagnostic scan using a reasonable scan tool (Preferably something a little bit more advanced than an chinese ELM327) - resolve any errors that are present due to faults (obviously ignoring anything related to items that have been deliberately removed)

Fill up with fuel

• Fill the vehicle with fuel, if filling with pump fuel and wanting maximum performance then find a shell garage and fill with V-Power or a Tesco garage and fill with Momentum, otherwise fill with whatever fuel your remap will be optimised for.

Bodywork

• If you're not driving your vehicle to the dyno and you need to remove low hanging bodywork in order to load your vehicle on to a trailer or recovery truck, now would be a good time!
• Remove any loose/hanging items from the outside of the car - in the dyno cell there will be a strong fan aimed at the car

Interior

• If you have a snap off steering wheel, don't forget it - whilst it won't stop your day, it's pretty annoying to move a car with no steering wheel

Trailer

We won't go into much detail on this one, as not everybody transports using a trailer but here are some high level checkpoints

• Check adapter for light board is present if required (13 pin to 7 pin is common these days)
• Check road lights
• Check tyres are legal and free of cracks/damage
• Check handbrake is in working order
• Check overrun brakes are functioning correctly
• Check correct tow vehicle number plate is attached to light board
• Check tilt operation functions correctly if applicable, or check that ramps are present and correctly stowed otherwise
• Check winch operation/grease as appropriate

That should hopefully cover the basics to make sure you get the most out of your ECU remap, please let us know if you think we've missed something!

Hakosuka Technology is a leading provider of Mobile ECU remapping in Essex.