Engine Under Shield - Enhanced Efficiency - DIY

[Tools R Us]

The factory location for air intake is in the passenger fender and for the most part is closed off except for one section to the engine compartment. So as temp under the hood rise the intake temp will go up because a lot of the air is actually from the engine compartment. ...

When stopped, agree, but when sitting in traffic I really don't care how much more potential HP could be made. At speed, there is excess airflow through the grill. This flows behind the headlights, some spills through the holes there, the rest flows behind the corner light into the fender well, feeding the intake.

Try this; put a temp prob on the intake tube to the air filter can and one measuring fan output temp. Do a varying speed run, note temps, they will be much closer to ambient, depending on speed, very close. Then remove the corner light, repeat the same run, the temps will match fan output. So the intake was well designed to use the coolest air under the hood, or it was an accident.

 

[Tools R Us]

Yup! Once the MAF is heat soaked that also means the entire engine bay is heat soaked and factory intake will suck up the hot air. ..

What effect does heat soak have on the MAF? People get spun about heat soak, it's normal.

Given the little power we got, having such hot air will rob even more power from our poor little....er big engine. Cooler temp = denser air = more oxygen = power suck less.

Power, got to have it! IIRC, from back in my go fast motor building days, 10 degrees IAT change is about 1% HP change, maybe. Installed my first '80 dorkel on a buddies LX in late 2004, have observed since then, often travel with a flock, some with some without. Agree, when sitting in traffic, there is a difference, at speed, 10 to maybe 20 degrees, so 1-2% HP difference. Most dyno techs would agree, not enough to be detected. On full throttle hill climbs, nether has any advantage, didn't then, doesn't now, has been repeated hundreds of times, with lots of rigs.

Back in the early days, someone stuck a temp probe in the plenum of a S/C rig, saw the alarming temps, hundreds of degrees above ambient. The Mud mantra became, all S/C rigs need a dorkel for the IAT and ram airflow benefits. Until some smart guy modeled the stock tube and dorkel in a fluid dynamics program, IIRC the outcome: The extra length of the dorkel caused it to be more restrictive. At ~600mph the dorkel theoretically could make ram air to equal the S/C, at ~100mph made enough to overcome the restriction. At more normal speeds, the restriction loss was more than the IAT drop gain. These are all very small numbers, maybe seen on a gauge, but no real world benefit.

 

[Tools R Us]

...
Given the little power we got, having such hot air will rob even more power from our poor little....er big engine. Cooler temp = denser air = more oxygen = power suck less.

If you want to make a real difference, go active, intercooler, water, alcohol injection, etc. Alcohol injection can easily cool well under ambient, pretty big number gains on the gauge. But again, on N/A motors, has been proven to be pretty much useless in the real world.

Dorkels are for fording deep water, on my rig that would be over 4 feet deep, or more than I am comfortable with. Lots of other mods are needed to do it and at that depth, are risking the rig. Other than that, they are pretty much peacock, good at attracting attention.

 

[Tools R Us]

You don't happen to have any pictures of the foam do you?

I should shoot one of what we do, but it's pretty easy. Using weather strip ~7/16 x 3/4" self adhesive, go across the upper tank at/on core seam, and across the front face of the lower tank, then down both side frames. This is done on the front side of the radiator, the idea is to seal it to the core support, so air can't get around it. Using window A/C foam, ~1-1/4" square, we add a strip across the bottom of the lower tank, stick it on with spray adhesive. The idea is to seal the air hole under the radiator to the frame rail/cross member.

 

[MoustacheMike]

I have never seen any documentation other than being designed for fording.

IIRC...

The documentation for the Denso snorkel says that it was designed to improve airflow (30% increase) and decrease system pressure drop.


* Denso Snorkel is for Hilux 05 - current *

 

[Tools R Us]

IIRC...

The documentation for the Denso snorkel says that it was designed to improve airflow (30% increase) and decrease system pressure drop.


* Denso Snorkel is for Hilux 05 - current *

Agree, some other types of rigs have poorly designed intakes. In the Cruiser world the FJ60 is a good example. Draws the intake air from behind the headlight, so by doing a correctly driven ford, pushing a bow wave, water is pushed right into the motor. Lots of other rigs benefit from intake relocation, 4Runners, minis, etc, not so much on the '80 it's well designed for the task.

 

[Qball]

When it comes to heat soak the entire engine bay and everything thing in it is hot. Every item has a thermo capacity and take certain amount of cooling to cool down. So once heat soaked the engine bay is hot Including the fender, take a good while to cool down and the way Intake suck air from fender and engine compartment the air will be hot for a long while. With snorkel only the intake tube, can and MAF have to be cooled down to get cloer to ambient air to the engine.


We can argue all day long but real world result for me and many other people is much cooler IAT and a little better low RPM throttle response. The power gain can be argued because there is no Dyno result but cooler IAT is measurable and repeatable. My IAT was 150-160 in 100 degree weather and now it's 5-10 degrees above ambient even at slow speed, even in 110 weather the other day my IAT is no more than 120 while sitting at stop light.


Yes at high speed snorkel does not make as much of a difference but we have long established that, it really helps with slow speed high IAT and really helps when following other rigs in dusty condition(that's every trip for us).

 

[bugsnbikes]

Qball- what snorkel are u using? dorkel or other?

 

[Qball]

Qball- what snorkel are u using? dorkel or other?

I have the OEM snorkel which has what I called the darth Vader head, it does has a air pre cleaner inside. I'm on the fence on the look and it does create enough wind noise to be noticed....at least by me. The other problem is that installation is a bit harder and the hole you have to cut is NOT a simple round hole.

If I had to do it again I would go with cheap eBay snorkle, cheap, easier install and I like the look of the air intake head and a little less wind noise at speed.

 

[SmokingRocks]

i see both sides of this debate. But, I have noticed that when stopped after running up mountain passes at wide open throttle I can put my hand on the intake manifold. Its cool, the engine bay is cool. Snorkles are in essence a cold air intake, and any high school car modder can tell you the benifits of a CAI.

May it be minuscule? Sure. Personally I could care less about the "horsepower" gains and more about the added cooling.

 

[Bambusiero]

Cool idea. Any numbers on how much it helped?

No, not really. My truck is in overheat mode, depending totally on speed/load and it might be progressing, plus it's hotter than the Gates of Hades in Phoenix these days.
I can't see much difference, but there are too many variables. Minor, as others have said.

That looks really good. Skills I don't have

Toyota Makes a part for that piece.

Check out my thread about it:
Is there a lower engine cover for the fzj?

(1) Engine Under Cover (Splash Shield) 51441-60190
(4) Bolts/Washers 90119-08863

Thanks for adding the link. I think that's what I finally found, after my project was mostly done.
That's OK, it was a bit of fun. First chance I've really had to try out the Williams Low Buck Tools bead roller that I got a few years ago. Making the pattern was much more work than making the actual part, and making it out of flat thicker stock would save time. With the beads in thin stock, it's very light and quite stiff.

Nice work, is the design available in a digital format so that others could print it out?

Thanks. Sure it's available. Already posted above, coded in the "JPEG photoCAD" format. (Save Image As...)
I recommend using the commonly available open source MeatWare Format Translator, and then Sharpie Vector Renderer as a final step.