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Old 06-13-14, 11:28 PM   #31
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Final two pics. 1) Primed, painted, and mounted in place. 2) Ground level view. With the shorter height on the second mockup, it extends halfway down the upper bumper opening. I thought it would fill the whole opening based on my test fit. I imagine that'll scoop up more than enough air as-is, but I could always extend a rubber flap down a bit lower if needed to catch more. I assume the stock setup works largely by suction, being a low pressure source of air, so at the very least this will flow as much as before since the snorkel's original opening is still there and has been supplemented along the bottom.

I ended up not using the intercooler bolt hole on the side that it lines up with, as everything feels rock solid.

While I had the headlight out, I figured I would try repositioning the high beam on that side, since it doesn't quite line up flush with the bumper, as seen in the first pic. No luck. Between the three mounting points and the tab at the bottom, there doesn't seem to be much wiggle room. Oh well, something in the frame or bumper cover must have gotten warped over the past 20 years.

I also tested all the bulbs as I was putting things back together and noticed that the driving light on that side doesn't work. I'm guessing it's been out all along and just doesn't have a failure indicator on the gauge cluster like many of the other lights. Has anyone replaced one of those bulbs and remember the part #? The best I can figure is it's a W5W 12V 5W bulb, but lots of very dissimilar bulbs also fall under that classification. Other markings on it include 7G KOIT E4.
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Old 06-14-14, 11:17 PM   #32
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it's a 168 light for the city lights
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Old 06-14-14, 11:39 PM   #33
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Thanks. I see some #168 listings that look like the same thing. And of course some that look completely different. I guess there are various xenon and leds that fit the same bulb size, similar to what I was seeing for the W5W lookups.

My temperature ****'s light went out today, as well... Maybe I can just switch the unused volume one over. And I'm low enough on gas that I might get to find out if my low fuel light works. I'm thinking not, since it doesn't come on with the other warning lights when turning the key to "On".
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Old 04-23-16, 02:30 PM   #34
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Originally Posted by t2d2 View Post
Have you read the whole thread? It's quite clear to me that very little measurement went into designing the typical BFI for ideal airflow. As I said above, it works by blind luck, not by science. That tells me it can be improved upon.

Right from the start, the "B" in BFI tells me it's an erroneous approach. Big has nothing to do with why it's an improvement. The stock snorkel is sufficiently big to provide as much air as the intake tube behind the filter can accept. It's actually 50% bigger, so you could get by with a smaller than stock snorkel and have the same performance as the BFI. It just needs air from a pressurized source. That's probably why Lexus put in an oversized snorkel, since that's low pressure air behind the headlight. That also keeps the filter clean and dry.

Opening up the airbox for a large volume is not the answer. At least, not in anything but a sledgehammer approach. If the BFI were better thought out, it would just be a tweak to the stock snorkel, routing its open front end over to the radiator cowl flap. Admittedly, that's a very tight space to work with and options are limited. Which is exactly why I started this thread to discuss better ways of doing things.

What happens if that radiator cowl flap that is being bent out of position to supply high pressure air somehow fails, either from the bolts loosening up or the plastic itself cracking at the washers? It is subject to very high wind forces in a manner it isn't structurally designed for, after all. Suddenly, you're choking the engine of all airflow, since you've sealed off every other entry point. That's why I said I'm not fond of that approach. If I end up pulling air from there, it'll be with an actual hose dropping down into the bumper opening.

I haven't yet come up with a good plan for how to pull air from the right bumper opening (the intercooler area) and up to the stock airbox without a lot of sharp bends back to the front of the box... There's something workable there, I just haven't settled on what yet.

I'm thinking dual 2" pipes straight up from below, lining up with the bottom of the box. That's just enough space internally to clear the filter. What it would do to airflow characteristics in the box, though, is a tough question. Once pressurized, maybe it doesn't need to point straight at the filter? Dual 2's is a bit on the light side, so I would probably supplement it from an additional hose or two over from the radiator cowl. That should exceed the intake hose's volume further down the line.

I'd also need to cut a new panel to glue in for sealing the stock snorkel on the front of the box, otherwise all that pressurized air just hits the back of the headlight.

I think you hit the nail on the head with this. I also think that the BFI mod isn't as well thought out as it could be, and it's gains minimal from stock.
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