Air Vent Modification

[Bill-N-Donna]

I received some advice the other day in which someone told me I should drill a couple of holes in the front of the vent intake to allow more air flow into the engine. I’ve heard this in the past and know that it can increase mileage somewhat but my problem is this. I don’t want to just drill a couple of holes in the air intake. I feel that Ford designed it the way they did for a purpose and if it did in fact help the performance or increase the MPG then why didn’t Ford build it this way to begin with?
Has anyone done this?

[racerjoe]

Are you drilling into the box that holds the filter ? Another thing,will the holes be directly exposed to rain when driving down the road? If the holes are still under the hood, i don't think they will make much difference. more air would help under extreme conditions, but typical highway driving while towing I believe there is sufficient air to handle the load. Remember,most hi performance applications that use more air "etc" are used in extreme conditions and do not make much of a difference in everyday driving.

[Gramps]

Are you refering to the panel behind the grill? If so, yes, I have done it. If you locate the intake tube that goes from the front of the engine compartment into the airbox, you'll notice the end of that tube sits almost against the panel behind the grill. Taking the grill off and cutting a hole where the tube ends does a couple things for your performance and MPG. Diesels perform better when they have cool dense air passing through the intake. The newer trucks were helped with the addition of an intercooler which acts like a radiator to cool the incoming air. By opening the hole in front of the intake tube, you force a larger volume of cooler air into the intake. The engine is able to get more air, and since the air being drawn in is not the hot air from the engine compartment, the engine performs better and produces better mileage. The increase is not earth shattering, but every little bit helps.

The addition of a larger intake system and the 4" exhaust is popular with many diesel folks for this reason. More air in = better performance, less restriction in the exhaust = lower exhaust temps and fewer turbo problems. Both are good things when you tow.

A little lengthy, but hopefully explains the whys of this modification.

[NCFischers]

I installed an K&N air intake and a Banks 4 inch exhaust on my TV and noticed a big improvement in performance and fuel mileage. I could feel and hear the engine running better. It didn't sound like it was being choked anymore. More air in and less restriction in the exhaust made a noticable improvement.

[Gramps]

After re-reading your question, let me clarify my response.* You don't want to drill holes in the airbox itself.* Increased air intake would be better served by installing a high volume intake such as the K&N NCFischers was refering to, or any of a multitude of other brand high intake systems. In my case, I installed a do it yourself filter system which uses a large round filter from NAPA.* When using the stock filter/ airbox, the hole I refered to is drilled in the flat pannel behind the grill, which allows the intake tube for the airbox to be exposed and act like a ram air intake, forcing more air to the engine.Hope this all makes sense.

[Bill-N-Donna]

Thanks for your thoughts on this! The way Gramps described the air intake box is the way it’s set up on the F-350. If I do anything at all I would replace the intake with a complete new intake. I can’t make myself drill holes in the intake panel. If I drilled the holes there wouldn’t be any un-doing it, I would just have to live with it. The other way it could at least be put back to normal if I wasn’t satisfied with it. I’m just going to leave well enough alone for now!