Has anyone tried running accel plugs in the 318? if so how did they work out? just curious before i buy them as they're a little pricey

 

i saw a chart of all the engines special U shaped plugs were designed for, and the 318 was not on there

 

U shaped ones work fine from what I hear. They are similar to the V-power type of NGKs that work very well.

Take a look at the spark plug threads in the FAQ section for more info on which plugs are most common and which ones to avoid.