If you’re trying to figure out how to tune your HPI Savage XL Octane’s engine, you’ve found the right place. Before you begin, remember that the Octane’s engine needs to be run with the factory settings for at least two to three tanks of fuel to allow the engine to break in. Don’t try adjusting the engine until the break in period is over.
High End Needle
For performance you should only need to adjust the Octane’s high end needle (marked H) so for the time being keep the low end needle (marked L) at the factory settings. Also, only change the high needle 1/4 of a turn in either direction from the factory settings, and only 1/24th of a turn at a time. To begin tuning the Savage Octane, make sure the engine is fully warmed up and grab a small thin flat head screwdriver. To get more performance from the engine, begin leaning it out by turning the high needle 1/24th of a turn clockwise and test it out. You can continue to lean the engine out for more speed as long as you always see a trail of smoke coming out of the engine.
If the high end needle is too rich the engine will have a deeper exhaust note with sluggish performance. If you experience this begin turning the high end needle clockwise 1/24th of a turn at a time. If the high end needle is too lean the engine will have a higher pitch exhaust note with little to no smoke coming from the exhaust. If you experience this begin turning the high end needle counter clockwise 1/24th of a turn at a time. Tuning the engine is a compromise of leaning it out for performance while keeping it rich enough so the engine runs cool and gets enough lubricant from the fuel.
If you think you may messed up the high end needle setting you can always return it to its factory setting by turning it all of the way in (clockwise) until it stops, then turn it out (counter clockwise) one full turn.
Low End Needle
Tuning the low end needle is very much the same as tuning the high end needle. If your Octane accelerates slowly from a stop you can lean the low end by turning the needle clockwise 1/24th of a turn at a time up to 1/4 turn maximum. You can return the low end needle to its factory setting by turning it in all of the way (clockwise) until it stops, then turn it out (counter clockwise) 1 1/4 turns.
After adjusting the needles you may need to adjust your idle speed so the truck doesn’t move when at idle. If the truck stalls at idle, then raise the idle speed by slowly turning the idle screw clockwise. If the truck creeps forward at idle then you’ll need to lower the idle by turning the idle screw counter clockwise. To return your idle screw back to the factory setting, turn it all of the way in (clockwise) until it stops, then turn it out (counter clockwise) 2 2/3 turns.
To get a better understanding of how to adjust your Savage Octane’s engine be sure to check out the video above.