Holy crap, I just drilled out my air box and I never knew it helped that much. It seems to be able to achieve boost much quicker. And (even thought I only have the stock boost gauge) the boost gauge pegs out quick and runs up to what seems to be 12psi. I have got to get an aftermarket gauge now. I love this truck!!!!

 

How big did you make the holes? What size bit and how many holes?

 

Drilling four 2" diameter holes (the largest diameter holes that I could drill while still maintaining some degree of strength in the bottom of the airbox and providing the same area that a single 4" hole would have provided) in the bottom of my airbox netted me exactly no increase in boost, no additional intake noise or blower whine and 7.7 rwhp and 7.3 ft.-lbs. at the maximum and an average of 3.9 rwhp and 3.9 ft.-lbs. across the rev range. It also leaned out my air/fuel ratio by about 7/10th's across the upper rpm range so it definitely pulls more air. But it's no where near adding 4 lbs. of boost...the stock gauge sucks.

 

I didn’t drill holes I just cut the bottom out. The part in the bottom that drops down lower is now gone, so I guess that would be about a 4x6” hole. And as far as gaining 4lbs of boost no I don’t think I did. The most I had been able to pull on a 26 deg night was 10 # and now, tonight, it was buried way beyond that. And I always thought the gauges sucked too until my friend hooked up his auto-meter with his stock gauge and the stock one was dead on. But I know, just like anyone else, that could have been a fluke!

Borrowing from the above pic this is the area I am talking about that I cut out.

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