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Discussion Starter #1
I have searched the stickies and the threads and can not find any info on cold air intakes. This is an easy mod and would cost little but what advantage or increase will it make. Do you think it would make enough of a difference to even woory about it. This is what I am thinking, routing air from out side the engine compartment into the air filter housing either it be some type of ram induction, hood modifacation, or just ducting to the out side of the engine compartment, mabey using the 08 superduty fender vents?, to pull in ambient air rather then engine compartment HOT air. In therory I know it will help, but in the real world is it enough improvment to warrant the extra day or so of fab work? Let me know what you guys think?

This would be on an aftercooled 4bt hx35w set up.
 

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A hundred degrees or more difference..... it is just that much more heat not going into the turbo, that much more heat not going into the intercooler, and that much more heat not going into the engine. Any simple modification to decrease heat flow into the engine is a good mod in my book :beer:
 

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Discussion Starter #3
My thought exactly, cooler air even before compressing it will equal cooler air after compressing right? Thanx.
 

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If you fab the cold air intake make sure it is hooded and has a provision to drain the winter road salt & water spray that get in the air when you are behind another vehicle.
 

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Discussion Starter #5
I was planning on an aluminum box with a plexiglass or lexan cover. I didn't think of the drain though thanx, I am not sure of how I will get the cold air in yet but I think a scoop behind the front bumper on the right side is going to be the best place to locate an air scoop.
 

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scoops behind the bumper are a touchy subject. hit a puddle wronge or deep water and you could suck in alot of water real quick.

all the cold air boxes ive had either draw off the cowl with the positive pressure of the windshield pushing down or the front section of the hood behind a headlight..... away or shielded fromthe heat radiating off the radiator and the shroud
 

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Discussion Starter #7
I have thought of that, the location of the scoop would be 28" off the ground, I have been known to Ford creeks before and this is too low to do that, a scoop on the hood was an option I think mabey I'll have too look at the hole picture again and revise the location. The factory cowl location has been taken away by the enormous intercooler I used.
 

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remember that a forward scoop contends with dropping air pressure where as a winshield provides positive flow back onto the hood.

intercooler up by your windshield cowl?

most the intercoolers ive seen that is airto air coolers are located in the grille or radiator support. and if it is an air/water aftercooler its usually on the oposite side of the air intake.

on DTR this was discussed and tested numerous times. drawing air from under the hood but isolating the box fromthe heat of the comparment yeilded results withing 25* of a reverse scoop pulling air off the winshield or a scotty air ram that utilized a hole and drew air through the cowl
 

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Discussion Starter #9
I should of stated the factory local on the core support, not the cowl, has been taken over by the intercooler. My bad, the fingers didn't type what I was thinking.

What your saying is that simply isoloating the intake into a box and away from the heat of the rad would almost be the same as a ram air set up?
 

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like that picture with a heat shield is sufficient. ram air doesnt seem to help much on a turbo charged engine.

the cowl system wasa 4" hole cut through the fire wall and into the cowl. it worked well because it was the freshest air without out any negative air pressure to contend with. but eh underhood setups with the heat shield are sufficient and dont tend to have the water accumulation problems. the cowl system used to get alot of water on the air filter in heavy rain storms. never had any issues but it was very concerning.
 

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Discussion Starter #12
I wonder if I routed ducting from the air filter box to the cowl air duct if there would be extra engine noise in the cab, If I routed the ducting to the cowl and had drains in the air box there probably wouldn't be much of a water problem. I will look and see if this is even possable.
 

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The benefits of ram air are nothing at the speeds our rigs can travel at. If you can hit 300km/h then you'll get a benefit.

So just make sure your intake gets fresh air, don't point it forwards or it'll probably just collect insects and road debris.
 

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You can also run a snorkel to a Donaldson cannister type air box. It has provisions for water to drain out (valve).
 

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From what I've just read (TDR issue 59) about cold air intake systems:

1. For every 5.5 deg F increase in air intake temp reduces engine power by 1 percent
2. For every 1 deg F of cooler intake air will reduce EGT by approximately 1.5 deg F.
3. Cooler intake air reduces under hood temp.
4. A sealed air box allows the engine to cool down faster than a open air intake.
5. Cooler intake air improves mileage. Every 10 deg F drop in intake air increases mileage by 1 percent.
 

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Another consideration per McGrady's, which is the same setup I use: build a double walled box with the sealed interior providing air to turbo, and area between inner and outer walls of box cooled by outside air, water saturated or not. The more water vapor in it the better!
 

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I'm working on a '62 chevy pu. In those models there is a bay under the windshield valance. On the passanger side there is a plate leading to this on the top of the firewall. I think this was used for the factory A/C air intake. Since I don't have air I could use this factory hole and make a box on the inside for the air filter. If I had the factory air box that was mounted there I could use this box to mount the air filter in..... You got me thinking... I better just get it running first.
 

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What about using an OEM Dodge Ram Air box? They are realativly well sealed, are good enough for a stock common rail (325/610) 6bt, and are dirt cheap on E-bay. Plus, you can get air filters at Checker or Autozone, OR run a K&N unit. All you would have to do is Sawz-All a hole in the inner fender to allow air to be sucked in. Space permiting, my thought is this would be an ideal solution. The 4bt I wouldn't think needs a huge conical air filter, they just look cool.

In fact, if it fits, I plan to use one on my CJ3 project...

Your thoughts?
 
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