I've decided to tap my air horn instead of getting the boost bolt, will I get a true reading from the air horn, if so where should I tap it at, does it matter? When reinstalling it, do i just hand tighten the bolts holding it in place, or do they have a torque specification?

 

Look at my pics. You can see my hook ups there. I took off the pipe boot going to the air horn and plugged the pipe with a rag. After drilling and tapping I wiped out the air horn to remove any shavings and debris.

 

Does it matter where in the air horn I tap?

 

No, it shouldn't matter.

 

No it doesn't matter.

 

here is where i drilled & tapped mine. i removed the intake horn completely when i did this...

 

When removing the intake what size are the bolts, and what torque rating are they? It looks like you got some kind of rubber boot on the fitting up near the horn, what is that, looks very clean, and factory!

 

the rubber boot is a rubber boot from an electrical alligator clip. 1/8" tubing that comes with the autometer gauges i "armored" with some 1/4" synflex air brake line [the black tubing showing]
i think the bolts were M8 with a 10mm head, but i am not 100% sure on that. as for torque, i just snugged them up with my 3/8" ratchet.

i don't have a 3/8" drive torque wrench and if i did, i still wouldn't have used the torque wrench on them... i am not saying this is the right thing to do, but there are many things that should be torqued, and some others that i don't think should be...