The split camshaft gear is an element of tuning the timing for domestic cars. It is installed instead of a solid gear and makes it possible to change the timing of the engine in a narrow range. Allows, "playing" the timing phases, to adjust the parameters of the engine, slightly changing its power and thrust. Tuning split gears are produced for all VAZ car engines and for the ZMZ-402 engine.
It is necessary
- Split gear.
- Dial indicators.
Instructions
Step 1
To adjust the split gear on the VAZ-2108-2110 8-valve engine, take this part in your hands and draw a mark on its movable and fixed parts. The mark is necessary so that the split gear can be installed in the same way as the standard one. Install the split gear on the camshaft and slide the timing belt over it.
Step 2
Check the coincidence of all marks, including the setting ones. To obtain the optimal (zero) position of the camshaft, check: the intake and exhaust valves must be open by a certain (equal) value specified during the design of the shaft. If not, loosen the outer split gear bolts and rotate the camshaft against the outside of the gear so that it aligns properly.
Step 3
Having set the zero position of the camshaft, carry out an additional correction of the valve timing. By cranking the camshaft relative to the crankshaft in the direction of rotation, traction at low and medium engine speeds can be improved. If you turn the camshaft in the opposite direction, you can get additional power. In this case, you should not leave the starting point by more than ½ tooth along the pulley. In the case of adjusting a carburetor car, each time the camshaft rotates, set the ignition timing again.
Step 4
To adjust the split gear on 16-valve VAZ-2110-2112 engines, install camshafts with split gears. Guided by the marks of the standard gears, approximately set the valve overlaps. Bring the pistons of cylinders I and IV to TDC and put on the timing belt. Install dial indicators and their bar (these indicators determine valve movement and TDC position). Find the closed (zero) positions of the exhaust and inlet valves of the IV cylinder alternately. After that, using split gears and indicators, set the overlapping of the inlet and outlet valves. Tighten the locking bolts on the split gears. Reassemble the engine and perform a test drive.
Step 5
Adjustment of split gears on 8-valve classic VAZ cars. With the split camshaft in place, use the standard cogwheel marks to approximate the valve overlaps. Bring the pistons of cylinders I and IV to TDC and put on the timing chain. Install the dial indicators with their feet resting on the rockers.
Step 6
Alternately setting the closed positions of the valves of the 1st cylinder and the exact position of the TDC, set the required valve overlaps along the split gear. Do not forget about the values of the gear ratios of the rockers and the point on the rocker against which the indicator rests. This will make adjustments to the overlaps. If installing an equal-phase camshaft, simply find its zero position (when all valves are open the same way), neglecting the values of the rocker multipliers. Lock the split gear, reassemble the engine and start.
