Airbox Mod (I know it's likely been said)
abovenbeyond
06-17-2008, 02:53 PM
Hello all,
I searched the forum and really did not read anything special about drilling the airbox.
I was thinking about leaving the tubing off and drill about 4 2" holes in it (3 on the top, 1 on the opposite end the tube connects to). Does this sound like a good idea?
What about the TBI bracket in the airbox, any real benefit in shaving it like I have read, I would think stock would be good, almost looks like it would act like a venturi, am I wrong?
I searched the forum and really did not read anything special about drilling the airbox.
I was thinking about leaving the tubing off and drill about 4 2" holes in it (3 on the top, 1 on the opposite end the tube connects to). Does this sound like a good idea?
What about the TBI bracket in the airbox, any real benefit in shaving it like I have read, I would think stock would be good, almost looks like it would act like a venturi, am I wrong?
silicon212
06-17-2008, 04:30 PM
Why?
abovenbeyond
06-17-2008, 06:39 PM
My thought is if I install the K&N and drill holes it will get me the most air possible, I know the draw backs of the hot air, but the only other option which I am considering too is plumbing straight tubing up to the grill for cooler air. I always doubt that technique because I feel like the air will heat up before entering the engine anyways.
silicon212
06-17-2008, 07:33 PM
Remember: The air intake system on your car was engineered for the engine in your car, to meet emission requirements and still provide sufficient air for the engine. Drilling holes in it isn't going to appreciably help with airflow.
This was a myth that has been going around as long as I can remember. I can remember being 16 years old and hanging out at a car repair shop (1985), and seeing a 1979 Caprice with holes drilled in the top of the air cleaner. This was explained to me that it increased airflow. So does flipping the lid upside down. When I tried it on my car back in the 80s, it made no improvement whatsoever.
Likewise, the cold air intakes do not add much either, beyond what your car is engineered to have.
This was a myth that has been going around as long as I can remember. I can remember being 16 years old and hanging out at a car repair shop (1985), and seeing a 1979 Caprice with holes drilled in the top of the air cleaner. This was explained to me that it increased airflow. So does flipping the lid upside down. When I tried it on my car back in the 80s, it made no improvement whatsoever.
Likewise, the cold air intakes do not add much either, beyond what your car is engineered to have.
abovenbeyond
06-18-2008, 12:14 PM
Ahh I see, Well maybe I will forget the holes, and just redo the plumbing up to the grill, minus the silencer chamber.
Thanks for your comments.
Thanks for your comments.
PeteA216
06-18-2008, 03:53 PM
Take into consideration... a stock 305 came with a very mild cam and fairly small valves making it hard for the engine to breath, especially at higher RPMs (anything above 4500 RMP). So basically what I'm saying is without heads with bigger valves and/or a higher lift cam, any modification in an attempt to improve flow going in or coming out of the engine will make very minimal, if any difference. I've tried a bunch of things when I had a 305 in my Caprice, including the trick silicon mentioned with turning the air cleaner upside down. **For some more MPG's one of those total-rip-off tornado's will help, but again only minimally (if that's a word). When I say minimally, only like 1, MAYBE 2 MPGs if you're light-footed. But I don't see why anyone would pay $65-$75 for a small piece of shaped aluminum.
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