Best Spark Plug

[scatgo]

What would be the best spark plug and gap for a thunderbolt ignition system? The engine is a 350 vortec.

 

[tpenfield]

AC/Delco are generally preferred on GM engines.

 

[Bondo]

What would be the best spark plug and gap for a thunderbolt ignition system? The engine is a 350 vortec.

Ayuh,..... What year,..?? If post-96, AC Delco MR43LTS,....

 

[scatgo]

Anybody know the difference between a MR43T and the MR43LTS?

 

[Scott Danforth]

the MR43T is for 1995 and older heads. the longer MR54LTS is for vortec heads (1996 and later)

 

[scatgo]

Thanks