Foot and head gaskets / Spacers for Long Stroke Crankshafts and higher Cylinders

Thicker base and head gaskets or Spacers are required for higher cylinders and cylinders with an extended stroke. When using a Long Stroke Crankshaft, half the length of the additional stroke must be compensated for by a head and/or base gasket. If the compensation is carried out using a base gasket, the exhaust times are longer and the overflow times are significantly longer. If the outlet is also raised slightly by milling, the Engine can be optimized for higher speeds. Compensation via a head gasket, on the other hand, only slightly extends the exhaust and overflow times, whereby the overflow time changes more than the exhaust time, i.e. with less advance. This favors a setup with more torque in the medium speed range.

If, for example, a 60 mm Shaft is installed on a MALOSSI 210 instead of a 57 mm Shaft, the 3 mm additional stroke must be compensated for by a 1.5 mm Gasket. The following then applies: 1.5 mm compensation at the base ensures a wide rev range and high horsepower figures, but also lower torque and a late and sudden power boost. on the other hand, 1.5 mm compensation at the head provides brute torque and wheelie danger in the lower rev range, but lower peak power. This is a particularly popular touring combination on the 210, also in conjunction with long gear ratios. Raising the POLINI 130 in conjunction with a 54 mm Shaft has also proven its worth, which is rewarded with power, stability and corresponding competitiveness.

Although the stroke does not change with a longer Conrod, the Cylinder must still be raised by the difference in connecting rod length. Foot seals are available in thicknesses from 0.5 to 10.0 mm, head seals in thicknesses from 0.5 to 2.0 mm. They are usually made of aluminum.

Conclusion: Long Stroke Crankshaft tuning with different Spacer combinations is one of the most exciting performance enhancements of recent years. This is where the wheat is separated from the chaff.