OFNA Racing Picco .12 R, 3 or 7 Port - Manual

Stop!! Carburetor LOW-END screw is preset by factory.... Do not change until you read
break-in instructions.
NEW ENGINE BREAK-IN
Your OFNA engine is extremely tight when the piston is at the top of the stroke and turning the crankshaft by hand. This is
normal for a new ABC type engine. The piston and sleeve are matched for fit and the top of the sleeve is tapered for a tight
fit. As you run your engine, this tightness should diminish. There is no cause for alarm, because as the engine warms up,
the brass sleeve will expand faster than the aluminum piston and the engine will turn freer.
As with any new engine, there are many high spots and tight fits in the matching process. High spots create hot spots that
must be broke-in. Therefore, the break-in process is very important to provide good service by the OFNA engine. So, you
must run the engine rich (COOL) for the first three tanks of fuel. We recommend using one gallon of 20% ODONNELL or
BYRON'S 2000 as break-in fuel. Other break-in type fuels or added oil is NOT needed. DO NOT OVER REV THE ENGINE
WHEN FIRST STARTING, this could break the piston and over heat sleeve. Let engine run at a fast idle for one tank to
break-in connecting rod bearing before starting full break-in. Let engine cool down before continuing and never stop engine
with piston at top of the cylinder. This cool down period is for heat cycling the parts.
Break-in the engine in the car, by running the engine at a rich master needle setting (3 turns or
more if needed).
Run the car from a slow to fast speed with short bursts of speed. You need to buildup a little heat
(warm to the touch) in the engine, but not too hot. In a rich setting (2 or more turns), the engine will run cold. In the leaner
setting (2 or less turns), the engine runs hotter. Do not heat up the engine too much at this time, let it cool down if too hot.
After about one (1) tank, turn the Master Needle Valve, clock wise, 1/16 of a turn leaner or clockwise. Keeping the fuel
tank full, continue the process until you slowly turn the Master Needle Valve, 1/16 of turn each time, too a leaner point and in
which the engine runs at high RPM and power, but still keep max temp. of under 250 deg. F. At this point you must stop,
too lean of a setting will heat up engine and damage the piston. A normal operating temperature is around 200 to 240 Deg.
Temperatures of 270 Deg. and above will damage engine and shorten life.
STARTING NEEDLE SETTINGS
Master Needle Valve - main control for fuel mixture. Set at 2 to 3 turns out from flush. Adjust this needle for maximum RPM
and power without being too lean or too hot.
Barrel Needle (Low Speed) - This needle is in the center of the carburetor barrel and provides throttle response. It is not
the idle adjustment. Turning screw "IN" is Lean and "Out" is Rich. Do not adjust this needle until the Master Needle is set
for power and best performance. This needle will only effect throttle response, so adjust needle until throttle response is
clean with little or on delay. Once set, do not continue to turn (lean) needle further. This is important since continuing to
turn needle will only increase engine temp, at lower RPM, which will throw off engine overall tuning.
Barrel Stop Screws - Used for adjusting Idle. Set for 1/16th inch gap to start new engines. You can open more for faster
idle.
USE LONG GLOW PLUG WITHOUT IDLE BAR,
STANDARD PLUG (OFNA/PICCO 51007 PLUG) IS RECOMMENDED
OR
TURBO PLUG (OFNA/PICCO 51006 PLUG) IS RECOMMENDED
OFNA/PICCO .12R 3PORT & 7PORT ENGINE
#51120 - .12R 7P TURBO PLUG, THREADED
#51121 - .12R 7P TURBO PLUG, SG
#51122 - .12R 3P STD. PLUG, THREADED, ROAR LEGAL
#51123 - .12R 3P STD. PLUG, SG, ROAR LEGAL