January 9, 2003my truck is a 350, and i keep hearing about the power robbing air box, i have a K&N, and i would also like to know the purpose of the airbox? silencer? Does anyone one know a simple, affordable, reliable way to increase the air flow? thanks for any help
January 9, 2003hold on there a second dude. the high-paid engineers have it there for a reason. the box actually is a heat shield for your filter, it`s a heat resistant platic so it doen`t suck in the hot air that`s in the engine compartment. if hot air gets cirulated into the engine, you`ll kill it over time. it keeps the air in box cool. the best mod to do is a "cold air" intake system (like an open element) with the filter IN the box-trick is to mold the box around the filter (no big deal).
if you`re extra creative, you could ram air the air box as well. my advice (which came to me from many many other mechanics) is to keep the air box, but mod it best you can without removing it.
as for the K&N, i have a repacment K&N, but only cause i ram aired my air box. without the ram air, i`d use a fram-the advertisment on TV is like any other. K&N`s extra added protection is what i`m after cause of the raw air i`m sucking in. i`ve read dyno tests that show very (and i mean very) little gains with a K&N, some actually showed a DECREASE, but then again, just about everyone`s truck and engine is different. hope some of this helps.
January 11, 2003
quote:Well, if that was the case then the combustion process itself would kill the motor ....all a warm air charge does is decrease power due to the fact that a warm air charge can`t hold as much fuel as a cold air charge....however that power loss is reletive to the the amount of air you are getting into the motor
if hot air gets cirulated into the engine, you`ll kill it over time
Say the stock motor makes 200 HP through the factory air box, you remove the air box and put a open element air filter on (oh no..warm air )and the engine now makes 210 horse power..but..you lose 5 horsepower due to the warmer air charge..you still make 205, thats a net gain
I know what cars_suck is saying though because for the most part the stock induction system will outflow the capacity of the throttle body...the stock GM TBI will flow between 600-620 CFM...now I KNOW that the stock Air cleaner housing, tube and air box will flow more than that, all you have to do is look at it and you can tell that, cars_suck is right in saying that the GM engineers spend alot of time and effort in designing that intake system to supply enough air to the motor as well as keep the intake quiet so that people don`t complain about engine noise.
The only reason that I would run an open element air filter (and I do) is for looks and for the sound that the open filter gives you...I have enough mods on my motor to overcome any minor losses that a open filter would give me
January 12, 2003The vast majority of aftermarket kits are open element, and there is a reason. Will the stock airbox and cleaner flow plenty of air? Sure it will, however it will require greater vacuum to do so. The additional filter surface area and minimized restrictions of an exposed element will add up to improved breathing.... it really is that simple.
Over at f150online, this debate went on to the point that people were taking underhood temp readings and breaking out the formulas for how heat affects output etc. Though I found it interesting, I thought there was an easier way to chisel through the BS. Simply look at the dyno runs of aftermarket intakes and see the improvements.
If you can provide more flow and less restriction in a sealed box which isolates the intake from engine compartment heat, this is even better. I think the main problem in this approach is space... it would take a large box and filter to match a cone type setup in flow potential.
January 12, 2003signmaster is right about the aftermarket filters being open element, and mabey my answer was a bit convoluted, so, yes an open element will probably make more power and the heat in my opinion won`t be as big a factor as you might think...was that any better ???
January 12, 2003there is a horn shaped peice inside of the large duct part above on the fender, some just pop out of the tube and some are part of the tube (easily hack sawed off,appearing stock).It is for noise reduction and is the only restriction, the rest of the stock setup works great. The duct goes into the fender and has several baffels so that water and dirt reaching the engine are minimized.Good stuff in you`re into wheeling. If you want and open element you can just flip the cleaner lid over and keep your money.
January 12, 2003Yelo,
I think that works well as a brief summary.
Actually all data I have seen indicates that intake temps increase very little with an open element. If you spend all day crawling at 5 mph under heavy load a sealed system might make sense, otherwise it probably doesn`t.
One of the most often looked aspects on an intake system is the velocities. If restriction is reduced too much with a huge open element, the vehicle will often actually loose some torque at lower revs.
As for the baffles and silencers, most can come out very quickly. While doing some work on my truck I noticed that my tube part was noted as "without baffle". From talking to people on the net and that I know around here, so far the only ones that have that part number designation are those with the later year trucks, which had higher output ratings. I may have stumbled onto one of the little secrets that let`s them bump the output over the years.
January 13, 2003do the deck plate mod: take a cutting tool and make a 4 or 5 inch hole in the air box. Go to your local marine store or another store that will carry marine deck plates. attach the deck plate and your all set.
cost: about 20 bucks, time: less than 30 minutes, savings: a whole lot
[ 01-13-2003, 12:45 PM: Message edited by: toyota-prerunner-guy ]
January 14, 2003please tell me in more detail about this deck plate mod please, im interested but not to sure what you mean by marine plate and where to put the hole