Blue vs Red Mercruiser Plug Wires

[jgoedd99]

Anyone know exactly what the difference is between a set of Mercruiser Blue Plug wires (84-7701A17) and Mercruiser Red Plug wires (81-6608A68). Both these are 454/7.4 Merc big block wires. My boat which is a 7.4 Mag MPI Horizon (SN: 0L006006) apparently calls for the Blue Wires, but i have been using Red. It looks like Blue cost a bit more than Red, so i suspect they are higher quality. Boat runs fine and I am not having any issues. Should i be concerned?

Thanks for the help.

JohnG

 

[Stee6043]

I don't have mags but I do have red wires. I'm betting you're giving up 3.5hp per engine with our lower grade plug wires

 

[Pirate Lady]

7.4 non-mag red wires, boat runs fine.

 

[Chris-380]

I have the blue wires on my 2000 7.4 MEI horizons

Anyone know exactly what the difference is between a set of Mercruiser Blue Plug wires (84-7701A17) and Mercruiser Red Plug wires (81-6608A68). Both these are 454/7.4 Merc big block wires. My boat which is a 7.4 Mag MPI Horizon (SN: 0L006006) apparently calls for the Blue Wires, but i have been using Red. It looks like Blue cost a bit more than Red, so i suspect they are higher quality. Boat runs fine and I am not having any issues. Should i be concerned?

Thanks for the help.

JohnG

 

[Pirate Lady]

Maybe the blue are for the newer EFI / Mag engines

 

[JimG]

Mine are factory blue... 350 Mag EFI

 

[Pirate Lady]

Mine are factory blue... 350 Mag EFI

Yep, i think we on to the reason here.