Relocate Air intake to cowl? (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Jul 18, 2011
Threads
55
Messages
941
Location
Bayfield, in the San Juan Mtns. of Colorado
Friend of mine has a Jeep XJ. The front intake on the airbox has been blocked off, relocated to the back of the airbox and a hose routed to the firewall, plumbed into the cowl below the windshield. Kind of a poor man's snorkel.

I wonder if this would work on an FJ60. It could easily mount over DS wiper access hole.

My XJ friend notes that there's a lot more vents in the XJ cowl. Based on how much air comes through the interior vents at anything over about 35 mph with no fan onI think there's enough airflow through the cowl on the FJ60 .

Might even get some "ram-air" effect from the low pressure area at the base of the windshield.
Thoughts?
 
You could prototype this relatively easily with some Kydex cut/formed to fit the wiper access panel with a pipe fitting epoxied into it that matches your air intake hose. Probably will need to use a more flexible hose like racing duct, but I think it would work well enough to get you a cowl intake if you don't need the extra height of a true snorkel. BTW the cowl/windshield area is high pressure but low speed, which is what you want for this situation.
 
I doubt it would gain you anything as far as performance or economy, so unless you're looking to free up the space used by the stock airbox, it doesn't seem worth it to me. If you want the function of a snorkel, I would just put some money aside for a legit snorkel.

What I'd like to do with my FJ62 (3FE) is install a snorkel, convert my AFM to MAF, and change out the airbox with a TRD cone style filter box that would allow more linear airflow (and velocity) through the intake at highway speeds and high throttle conditions, due to losing the tight right angle turn and flapper style AFM. I would much prefer to use an OEM Toyota dry filter though and not an oil/gauze filter.
 
Common upgrade on Ford trucks also. It is a high pressure area, and higher off the pavement, so maybe a little cooler. I've looked at those wiper access ports and thought about it, but haven't done it (yet).

It would be good to get IAT before & after mod to know if it is useful.
 
I've not the wherewithal to gather any scientific data so I shall have to rely on my analog sensors, i.e. Seat of Pants. ;)

BTW Jim, still very pleased with the dizzy from you. :)
 
Last edited:
I doubt it would gain you anything as far as performance or economy, so unless you're looking to free up the space used by the stock airbox, it doesn't seem worth it to me. If you want the function of a snorkel, I would just put some money aside for a legit snorkel.

<snip>

I'm not going to change out the airbox, just route the air intake hose from the grill to rear of the engine bay on the cowl. Will there be a better chance of preventing water getting into the intake than stock in the grill? Yes, in any kind of reasonable water crossing.

Will there it be as effective as a purpose built snorkel? No but those cost $150 for generic ebay to $300 complete quality. The cowl mount looks pretty good for ten bucks worth of pvc. ;)
 
You could prototype this relatively easily with some Kydex cut/formed to fit the wiper access panel with a pipe fitting epoxied into it that matches your air intake hose. Probably will need to use a more flexible hose like racing duct, but I think it would work well enough to get you a cowl intake if you don't need the extra height of a true snorkel. BTW the cowl/windshield area is high pressure but low speed, which is what you want for this situation.
More or less exactly what I'm going to do. It already has a flexy 'racing' duct on it that will easily reach the cowl.
 
That would be one way to clean out the cowl area and keep it clean could also run the ac and open up the flap for fresh air and send cool ac into the intake.

20200207_204149.jpg
 
I think most people use snorkels and ideas such as this as cold air intakes more so than for legitimate water crossings. I don't want water inside my cab, so I have less tolerance for depths of water I would be willing to cross (2-ish feet is more than I feel like dealing with). I have still been thinking about a snorkel, but I like this idea. Might be looking at it when I get home today. I would just be worried about debris and water from rain having direct access to drain from there down into the air cleaner (and thus engine). I am running a V8, this may not be an issue for 2F and 3Fe air boxes. I may be able to just flip my current air cleaner 180 degrees and run a short hose up to the cowl. It is just pulling air directly from the engine bay at the moment.
 
I think most people use snorkels and ideas such as this as cold air intakes more so than for legitimate water crossings. I don't want water inside my cab, so I have less tolerance for depths of water I would be willing to cross (2-ish feet is more than I feel like dealing with). I have still been thinking about a snorkel, but I like this idea. Might be looking at it when I get home today. I would just be worried about debris and water from rain having direct access to drain from there down into the air cleaner (and thus engine). I am running a V8, this may not be an issue for 2F and 3Fe air boxes. I may be able to just flip my current air cleaner 180 degrees and run a short hose up to the cowl. It is just pulling air directly from the engine bay at the moment.
Just be sure the v8 can get enough air . Ie. Don’t go small on the tubing.

there’s no such thing as a cold air intake here in PHX Az 😝
 
I know the feeling. It’s 108 here at the house.
 
More or less exactly what I'm going to do. It already has a flexy 'racing' duct on it that will easily reach the cowl.
Let me rephrase: It already has a flexy 'racing' duct on it that will easily almost reach the cowl. <sigh>
But I'm still working on it.
 
I think most people use snorkels and ideas such as this as cold air intakes more so than for legitimate water crossings. I don't want water inside my cab, so I have less tolerance for depths of water I would be willing to cross (2-ish feet is more than I feel like dealing with). I have still been thinking about a snorkel, but I like this idea. Might be looking at it when I get home today. I would just be worried about debris and water from rain having direct access to drain from there down into the air cleaner (and thus engine). I am running a V8, this may not be an issue for 2F and 3Fe air boxes. I may be able to just flip my current air cleaner 180 degrees and run a short hose up to the cowl. It is just pulling air directly from the engine bay at the moment.
I suppose I could flip my air cleaner box 180. . . there are a lot bolt downs and vacuum lines on the passenger side thogh. . . I should look at that. Did i so do the intake would angle back to the firewall. . . maybe plug into the middle wiper access port right under the vents. . . hmmm.

It would be easy to build a baffle if you plug into the driver's side wiper access. You're aways from the vents to atmosphere, so a baffle should keep water and assorted crap out of the intake.
 
After looking at mine again last night, I don't think it will work for my particular setup, at least not with the air box I have. Back onto the Snorkel Train.

On another note, two 120lb gas struts are not enough to support the FJ60 hood with the geometry I chose. Time to find some 200 pounders.
 
The rear of the engine bay gets very hot from the radiator air flowing into it. The top of the cowl also gets very hot on hot days with the sun beating down on it. Add them together and you get a hot box inside the cowl vent pocket.

Ever notice on hot days when turning on just the vent in the cab that the air blowing out is hotter than the outside air?
That pocket under the cowl is not a good location for engine air intake.
 

Users who are viewing this thread

Back
Top Bottom