OEM Crusader port exhaust manifold fits Crusader GM 7.4L & 8.2L big block marine engines.

Port Side Big Block Exhaust Manifold | Crusader 97993

• Crusader exhaust manifold
• For Crusader V8 big block 7.4L 454 cu. in. and 8.2L 502 cu. in. engines
• Port side
• Heavy duty cast iron
• Painted Crusader blue from the factory
• Original Crusader
• Replaces Crusader 96580 and 97115
• Replaces Osco 7993

Frequent Asked Questions 

With today’s rising gasoline prices, what octane rating is recommended for Crusader engines?

Crusader fuel injected engines are calibrated to operate on 87 octane fuel and maximum performance is obtained when using this fuel. The ignition timing set by the factory requires the use of a high-quality lead free regular gasoline with an octane specification of (R+M/2).

‏What kind of oil should be used in Crusader engines?

When the average temperature is above 50 degrees F., use a good quality SAE 15W-40 “SJ”. Below 50, use SAE 5W-30 “SJ”

Synthetic oils are not recommended for use in Crusader engines. 

What is Crusader's policy on the use of Ethanol?

This notification addresses the use of ethanol fuels IN CRUSADER ENGINES ONLY. It does not address the use of ethanol fuels in vessel related components such as boat gas tanks, boat fuel lines, boat fuel filters, etc. The boat owner is STRONGLY ENCOURAGED to contact the boat builder regarding the suitability of ethanol fuel usage in their vessel.

Ethanol blended fuel rated E10 or less is acceptable to use.

Fuels rated higher than E10 SHOULD NOT BE USED.

Ethanol fuels rated higher than E10 could potentially damage the engine and/or present an unsafe boating condition. Damage to the engine resulting from the use of ethanol fuel rated higher than E10 is not covered by the warranty.

What type of coolant should be used in Crusader engines?

Crusader recommends DEX-COOL or any good extended life coolant (pink/orange in color) mixed 50% DEX-COOL to 50% water for engines that have a closed cooling system. More than 50% coolant can contribute to overheating. Do not mix or substitute DEX-COOL with traditional silicated coolant (green in color).