Hybase® M-401

Hybase® M-401 is a 400 TBN oil soluble overbased magnesium sulfonate. It is typically used as a detergent and rust inhibitor in crankcase lubricants. Hybase® M-401 is compatible with most mineral base oils, white oils, and synthetic base stocks.

What is LSPI? 
Low Speed Pre-Ignition or LSPI, is related to modern high efficiency spark ignition engines that utilize direct fuel injection. It occurs at low speeds during rapid acceleration. A combination of fuel and oil pre-ignite causing uncontrolled combustion. 

What is the impact of LSPI?
This uncontrolled combustion can lead to engine knock which may seriously damage the engine. It is expected that more and more engines will face this issue as they are downsized and turbocharged over time. 

What are the causes of LSPI?
Several factors may be involved in LSPI – the fuel, lubricant, and the engine design. Lubricants themselves have been undergoing significant changes primarily to help improve fuel economy. These changes include the move towards significantly reduced viscosity, the use of different base stocks, the increased reliance on viscosity index (VI) improvers, and the increased use of existing and novel friction modifiers. Some or all of these may play a role in the phenomena. 

Effects of detergent chemistry
The effect of calcium and magnesium based detergents on LSPI has already been studied extensively by the industry. It has been discovered that overbased calcium sulfonate can promote LSPI while an overbased magnesium sulfonate detergent has no effect on LSPI. While formulators may be looking at several changes to their formulations to combat LSPI issue, it appears that the use of magnesium sulfonate will be a critical component in their formulation design. LANXESS offers quality overbased magnesium sulfonate to help with the LSPI challenge.