Air filters

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Your turbo can pull a lot of air (350CFM) threw your intake even if it’s restricted but that first big gulp off the stop light will take longer/more rpm to get that air resulting in later boost.

Compare it to a very dirty air filter you probably still get up to your 18 psi boost and drive fairly normally but you notice it’s a little snappier with a fresh filter.

My boost gauge also does vacuum but it’s probably not small enough increments or percise enough to repurpose. I already almost have holes in my flex pipe no big deal to poke a new hole, i should hook up my shop vacuum gauge and test this out.

What size lid outlet did Toyota give the 2LTE?

Actually got to this in a few spare minutes today. My filter setup is a different design than most cruiser ones, but still very effective with a cyclone effect that throws dirt into the lid trap.

Outlet metal pipe from my filter canister measures 2.55" outer diameter (just before rubber hose connection).

I'm ashamed to say I did have a (well maintained) K&N filter in there. It definitely flows better and filters worse, lol. But I don't notice the difference at spool up in any real way between filters. Just 1-2 PSI less peak capability with the proper filters compared to K&N. So I think it only is at really high flow there is any difference. Note the 350CFM figure was calculated at 4000rpm; so not something I'd hit very often! I think I came up with that when I was working at mapping different turbos I could upgrade to.

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Looks like the airbox intake might be a size up on yours. Which is good.

I keep going back to the HVAC math I had to do, with static pressure. How a certain amount of drop is expected after the fan (which in this case is the engine, so it doesn't matter) but before the fan is bad.

Our system had a tiny restrictive return and was generally built by idiots (story of my house 🤣)

Furnace filters have a number on them of the drop you can expect but more than that and the problem is the return duct being undersized.

I'm tempted to try enlarging the filter housing intake, on stock 40s it has several bends and ends up even smaller up by the rad.
I don't have that pipe on either truck because it can't be helping.

I suppose with a bit of ready rod and a flat plate, one could pop the lid off the airbox but still bolt the filter in place. That'd show which side of the filter is causing it.
 
On my constant project 40 series I already have enlarged the filter housing intake to 3 inches ID.
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It’s fairly easy to upsize that inlet, it’s thin metal but can be done, the rest of the pipe out of the engine compartment to get cold air would be the more finicky part. I have three inch pipe to the one side air louver I boxed in for my cold air.
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Most of the time I build something I build two so I use the best one. I have this extra stainless louver flange 3 inch if anyone wants one for free! Probably located too low for all you hardcore’s and the river crossings you guys do though.
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I haven’t gotten far enough to test it out yet. I’m also planning on upping my 60 series filter housing intake size as well but over 3inch that will be a fair bit more complicated.
 
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Looks like the airbox intake might be a size up on yours. Which is good.

I keep going back to the HVAC math I had to do, with static pressure. How a certain amount of drop is expected after the fan (which in this case is the engine, so it doesn't matter) but before the fan is bad.

Our system had a tiny restrictive return and was generally built by idiots (story of my house 🤣)

Furnace filters have a number on them of the drop you can expect but more than that and the problem is the return duct being undersized.

I'm tempted to try enlarging the filter housing intake, on stock 40s it has several bends and ends up even smaller up by the rad.
I don't have that pipe on either truck because it can't be helping.

I suppose with a bit of ready rod and a flat plate, one could pop the lid off the airbox but still bolt the filter in place. That'd show which side of the filter is causing it.

Some really good points there. Definitively the same technical theory in place here.

I thought of just clamping some screen over my turbo inlet to replace the entire filter system. Then go for a quick run after to get a feeling for the difference. Maybe on a rainy day to keep dust down, haha.

I might try a vacuum gauge setup like Steve has been doing, but run it into the cab so I can see high loads while on the highway. I have a nipple I see now just after the air intake temp sensor in the cannister outlet. Haha, reminds me I've been meaning (for 10 years) to test my intercooler efficiency with a pre and post temp sensor too. One of these days....
 
I've always thought a guy could make some decent cash selling a reproduction of the 1fzfe outlet pipe. I should find one, send it to a chinese manufacturing company to reverse engineer and replicate. Could probably make a tidy profit. Pretty sure Toyota has been out of them for some time.

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I have been looking for that specific lid for years. They are sold at wreckers as fast as they come in.
South Island wanted $850. Cause I had to buy the hole assembly. Look up the price new on
Toyota. Stupid. Which exact model and year is that air assembly you pictured from?
 
I have been looking for that specific lid for years. They are sold at wreckers as fast as they come in.
South Island wanted $850. Cause I had to buy the hole assembly. Look up the price new on
Toyota. Stupid. Which exact model and year is that air assembly you pictured from?

Hi Jon, I think I just searched on google for FZJ80 air filter. In any case, picture came from this thread: For Sale - 1996 FZJ80, 1FZ-FE parts, Chilliwack, BC, CAN. Part 2 of 2 - https://forum.ih8mud.com/threads/1996-fzj80-1fz-fe-parts-chilliwack-bc-can-part-2-of-2.628370/

Heh, that whole assembly was $30 used in 2012.
 
Yeah -

Air filter box c/w air intake meetering assy. (p/n - 22250-66050 - $560.70 !!! at Toyota) - clean with no rust. - $30.00

From that 11 yr old post. Can’t find them any more.
 
Yeah -

Air filter box c/w air intake meetering assy. (p/n - 22250-66050 - $560.70 !!! at Toyota) - clean with no rust. - $30.00

From that 11 yr old post. Can’t find them any more.

Like I say, there is money to be made there. Some investment for manufacturing dies/tooling, and then bang 'em out like hotcakes!
 
When you have hoarding tendencies like me you would have saved this air filter housing for a purpose you didn’t know at the time… but now! That reason i saved this has become apparent, I need to chop it up for improved air flow!
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Upgraded inlet size 3 1/2 or 4 inch?? from the housing to the front behind the grill.


Are you guys still running the factory top and bottom hard to find air element gaskets?

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Very nice.

I was looking at mine in the 40, and that intake necks right down to 2". Crazy really.

I'll have to modify the way the box mounts just to get it to fit,when I put the turbo in, so I may do something about that at the same time
 
I wonder if their theory behind the smaller intake was to increase velocity so the cyclone action was stronger?

Both my trucks have the sediment pot underneath (aka wasp trap) which gather up a lot of crap.

And dead wasps.

Or was it just because a 2" duct is easier to hide in the fender . Good chance it was just that and not anything technical I'm guessing haha
 
I'd say inlet size, bigger better. Consistent flow to the turbo. I should have taken a picture but my snorkel inlet was
worse than this because essentially the engine stalled from lack of air flow. 65 km off the S Canol road I damned near had a
heart attack. Thick willows. The lower catch can was over half full by this point. Cleaned it all out, spun the snorkel and
all good. I was almost shaking, just thinking of why? and knowing how long the walk was gonna be.
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Towing power when I went camping this last weekend was noticeably less than with the K&N. So I turned up the fuel a bit (electronic pump means this is just a potentiometer in cab) and got my power back a the expense of higher EGTs. But higher EGTs were still only 950F maximum pre-turbo, so not too bad I guess. Probably lost some overall efficiency if I had to guess.

Truck ran great though overall. Still can move 8500lb+ over the Malahat at greater than 75km/hr, and usually speed limit.
 
Sort of on the topic.

My air filter housing (60 series) flex pipe to smaller diameter (I haven’t measured yet) turbo is on its way out. Anyone found a suitable tapered flex pipe? Toyota part number? Or have a good used one?
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Have you done any digging on this yet?

I actually managed to use mine on my turbo install and it's looking like yours, not quite as tight a bend but probably close enough.
 
I have been looking and it’s going to have to be a custom multi piece thing unfortunately there’s nothing worthwhile available. The fact that tapers makes using a one piece flex hose not an option, interestingly that taper is by design to compensate for any restrictive flow caused by bends.

My thought is to use a 3 inch hard pipe with the bend and a 3 inch silicone boot to the air filter housing lid and a 3 inch silicone reducer to my 2 3/4 turbo so it’s three inch the whole way until it necks down right at the turbo.
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I swapped my factory 1985 bj60 lid to the less dimpled one that you were talking about I think came on the earlier bj60’s not sure it will make any difference but I did put a nipple in there so I can test the vacuum to find out.
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Almost ready to put the modified filter housing in also! But I have a bunch of work to do still on the stainless 3 1/2 hard pipe to the front grill.
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Also picked up header wrap to do my stainless exhaust down pipe to try to keep engine bay temperatures down.

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