what size drill bit was used? is it possible to bore out that bullet and the rail fitting?

 

.125"

you can bore them both out

 

i have a 04 lb7 federal emissions 2500 hd allison does my truck need it ihave put on a air dogtwo and put in 15%bigger injectors

 

OLD message, I know. Sorry.

But this is a terrific write-up! I did both of my fittings today and the low/mid-range power is definitely increased. Also she isn't sluggish like she used to be, throttle response is right there now.

Thank you for posting this 2500HeavyDuty!!!