So I've been trying to find a good DIY on the BFI mod and I've found plenty of good DIY's, but not too many great ones that show how to do it in specific detail. Any of you could direct me to a good one?

It seems like you just cut a big hole in the front of the intake and then make a top plate to prevent crud from getting in there. Am I oversimplifying it? Anybody know the do's and don't's of the BFI or how to make the best one?

 

http://planetsoarer.com/BFI3/bfi3.htm

Probably the clearest out there.

 

you have pretty much got the gist of it, except the cover is not to keep crud out, the cover helps seal around the box, so it will suck in the air from the spot under the headlight which is cold air, instead of engine bay hot air if you were to leave it uncovered and just do the hole.
making the hole will help a little bit, but still give you hot air.
doing both will help flow and cold air = more power.

 

Can we do a BFI for the SC300?
Everytime I see it mentioned, it's always in relation to the SC400, and I'm wondering if there is a reason it's never talked about for the 2jz-ge.

 

airbox is basically the same so yeah you can do it on either one. It is an SC specific mod, but it seems to help alot more on the 1uz the engine is a liter larger but uses a similar airbox, so you can see why its more often done on the v8 but it helps any motor.
before going turbo on all my SC3's I would make a larger hole above the stock snorkel, and leave the snorkel in place so it could still get some cold air, and the top hole would be more or less engine bay air. seemed to give it a little more top end.
If you go the extra step and cover it all you will get the max benefit as you can remove the snorkel and will only be taking in the cold air from under the headlight, but I never actually did the second step I am sure it would help though.

Its an intake don't over complicate it guys, more air is better, and colder air is better.
removing the stock box and putting a cone filter that only takes in hot air is arguably the same or worse compared to a stock box with just a drop in k&n. the problem isn't the size of the filter on the stock setup, its that the snorkel isn't as large as we would like it, so we remove it and seal up the area around the box and add more holes to the box to get the most cold air possible and therefore the best intake short of making a 3" hole under the airbox, running a pipe down there and putting your filter completely ouside the engine bay, but most don't want to cut a 3" hole in the car for a daily driver.

 

Why is the BFI always over complicated...?

Remove airbox, cut large hole in the front, done. Optional: make cover for top to fill gap between back of headlight to the box.

Will work for both 300 and 400, and will also work for na-t 300's if you chose to modify the stock intake pipe from the box to the turbo.

Have fun!

Oh, also forgot to add. Removal of the stock resonator box (large usless box mid-track on the intake pipe) will help with a bit of air flow, but will give a "growl" at WOT. And the stock plastic/rubber intake pipe wont heatsoak as bad as an aftermarket aluminum pipe.

 

How is the box removed? Never heard about it helping air flow but i would like to check it out.

 

I removed the small one on the bottom right after the air box, i used a cap from a oil bottle that was the same diameter to seal it.

 

Any other 400 owners cut that resonator/baffle out? what did you use to replace or cover it up?