Tuning tips, Fuel tps rpm btn 040 off off – BoonDocker POLARIS: Non-turbo Control Box 600/700/800 IQ Dragon User Manual

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BoonDocker – 2379 Heyrend Way Idaho Falls, Idaho 83402 – 208-542-4411 / 877-522-7805

www.boondockers.com – email:

[email protected]

– fax: 208-524-7381

Revised 1-15-08

Page 6 of 14

under certain conditions and safe readings can vary greatly from engine to engine depending on such things as probe
placement, fuel, timing, pipe design, porting, etc.

Tuning tips:

Important: Find the settings where your motor runs rich before you decide to go lean!

1. Tune with the engine and pipe at operating temperature. The sled’s ECU will make adjustments as the engine

warms up – you might think the engine needs leaner settings then later realize you are too lean once the engine
warms up.

2. Use the Load/Save Map feature to quickly change and compare fuel settings when testing. This can also be

useful for riding under different conditions. For example, changing elevations or temperatures may require
different adjustments if the stock ECU does not compensate properly for your modifications. For drag racing,
you might want to run richer settings for longer distances than you would for short distances.

3. One method for finding out where a fuel adjustment setting is effective, greatly increase only that setting. Run the

engine to find out when it suddenly becomes too rich – this is where that setting is effective. Be careful – you can
easily flood the motor, especially with LO load or low rpm settings. If this happens, to restart the engine you may
have to pull several times with the throttle held wide open.

4. The Stats Capture feature can be used to determine RPM, and if the load setting is LO, MD, or HI. The nitrous

button can be configured to capture these stats (see nitrous configuration section below). From the Main Menu,
select N2O, set Btn to CAP. Whenever the button is pressed, the Stats: Capture screen will be displayed. The
current stats will be captured when the button is released.

N2O Menu in “Capture” mode:

Fuel TPS RPM Btn

040 OFF OFF

CAP

5. The nitrous handlebar button can be used to add or subtract a preset amount of fuel for interactive tuning purposes

(see nitrous configuration section below). From the Main Menu, select N2O, set RPM and TPS to OFF, set Btn
to TUN and adjust the fuel number as desired for the test (see example menu screen below). When the nitrous
button is pressed, this amount of fuel will be added or subtracted immediately from the current settings for all
rpms and all loads.

N2O Menu in “TUNE” mode:

Fuel TPS RPM Btn

040 OFF OFF

TUN

Also consider the following:

A/F Mixture Generally EGT’s get hotter as the motor gets lean, but too lean and the temps can actually drop! It’s like

turning the oxygen up too high on a torch – as oxygen is added, the flame gets hotter to a certain point,
then gradually cools off until it becomes extinguished from too much oxygen.

Detonation

Detonation often requires an experienced tuner to detect – in most instances it cannot be heard or
noticed. Careful examination of the piston and sparkplug are required. Watch for melted sparkplug
electrodes, speckling on the sparkplug insulator, or shiny or gray flakes on the electrode which could be
melted aluminum from the piston. If possible, watch the crown of the piston (near exhaust port) for a
pitted or sand-blasted look. EGT’s can sometimes read low during detonation – heat is going into the
cylinder and piston instead of out the pipe.

Timing

Timing can affect the pipe temperature. Generally if the ignition is retarded, more heat will build up in
the pipe. Too much advance may drop EGT temps, but increase cylinder temps.

Fuel

Different fuels have different densities and other characteristics which can affect your mixture and fuel
requirements. Oxygenated fuel will run leaner. Octane rating is important for highly modified motors.

Lean spots

Sometimes a motor runs hot at certain rpms and throttle positions (usually in its mid-range) no matter
what. The fuel adjustment settings can be used to richen this up, but the engine may quickly become
too rich and run erratic. Under light load conditions you can sometimes get away with running hot for

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