Spark Plug Reach Owners Manual Vs Online
IFR6D10
ILFR6A
https://www.ngk.com/product.aspx?zpid=9791
https://www.ngk.com/product.aspx?zpid=9806
"The only difference in plug reach I'm aware of is M113K vs M113. The Supercharged engine has lower Compression Ratio, dished pistons, and a longer reach plug. Welcome to poor cross-referencing. I have always used the NGK 5344’s"
So I am going to take their advice and stick with the NGK 5344 haha




