great post with data shared were you able to clear up any restrictions for running 20psi on boost and what mods have you done?
The "Official" 1HZ/1HD-T/1HD-FT Airbox/Intake Mod Thread
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I think the only way he could clear restrictions on the stock airbox is a 4" in/out and better flowing filter.
Anyone done manonmeter tests to actually measure what's going on?
I swapped to a late model 1FZ airbox lid, and larger S-pipe to turbo, which did make a small but noticeable difference in performance (seat of the pants). I did not install the restriction gauge in the new setup to measure and compare however.
The pipe between the airbox and the turbo inlet. I cut the flange off so you can slip the silicon elbow over the airbox outlet, and had a custom S-pipe welded up by a buddy.
I'm going to chuck a spanner in the works here - as I'm about to launch into attacking my 80 to fit a 4 inch custom stainless snorkel, I got wondering if anyone has taken the standard air box of an 80 (ignore the lid part). and modified the inlet to be a full 100 mm (4 inch) opening?
I realise my 80 does not run a turbo motor (yet), but the obvious flow restriction for air through the snorkel is (a) the inlet to the pipe itself via the ram head and (b) the outlet of the pipe where it will go through a couple of hose adaptors to join to the air box inlet proper once the factory box intake bit is removed.
Does anyone make replacement air boxes exactly the same design and mounting as factory (to use the same Toyota filter element) but with a big 4 inch inlet?
I see heads of custom air boxes that use pod filters but without being a skilled flow hydraulics engineer I can't understand how, apart from looking blingy, they are 'better' than stock air boxes in an 80.
I realise my 80 does not run a turbo motor (yet), but the obvious flow restriction for air through the snorkel is (a) the inlet to the pipe itself via the ram head and (b) the outlet of the pipe where it will go through a couple of hose adaptors to join to the air box inlet proper once the factory box intake bit is removed.
Does anyone make replacement air boxes exactly the same design and mounting as factory (to use the same Toyota filter element) but with a big 4 inch inlet?
I see heads of custom air boxes that use pod filters but without being a skilled flow hydraulics engineer I can't understand how, apart from looking blingy, they are 'better' than stock air boxes in an 80.
TorFab has a nice panel filter from a duramax or LS1 with 4" out, you will prolly have to ask or build yourself the back panel 4" snorkel adapter.
You can check out my thread what I have done or IG @cruiserbruiser369
AussieHJCruza
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I can't see how the pod in a box setups are any better either, but I had good success with a moonlight airbox in my TD 80. Runs a dry Donaldson filter, not a K&N or something.
Yes, see the first page of this thread in Post #2. There was another one shown in Post #51. I didn't go any further to see if it was completed.
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Hmmm, I'm not running a turbo motor but would be interested in a modified factory airbox (or direct copy of) with a big inlet (4 inch nominal) instead of the tapered one that the factory ones have. Do the turbo air boxes have a different design of the box itself or is it only the lid that's different?
you can swap lids from the 1fz to the turbo diesel 1hd-t/1hd-ft only modification needed to do is the wing nut bolt needs to be longer
That's not the only mod needed if you want it to be attached to the turbo inlet, where the tube connects to the lid also requires some modifications as there's a flange on the 1FZ lid that needs to be cut off, and the bends in the tube will be different as well.
Can I please have more details on how you did this. What size couplers and what size pipe you went to?
Whatever the 1FZ airbox lid outlet is (3.5" I think, it was a while ago), that's the size pipe I used between the airbox and the turbo, the elbow at the turbo is also a reducer to 2.75" (again, from memory, Gturbo inlet is larger than stock turbo). The hardpipe was a custom piece, nothing fancy, single bend to meet the turbo inlet coupler. Clamps are the fancy T-bolt style, probably overkill as these connections are only ever under vacuum, not boost.
This is a great thread with lots of information and insights. I am considering getting a snorkel and airbox from Fabwitz. I think their snorkels look great and are well priced. I have an 81 HDT 96
Does anyone have any experience with Fabwitz? https://fabwitz.com.au
Secondly, would the shape of the air intake make a difference? They have a round one and a slightly shaped on that costs slightly more.
Thirdly, they do an airbag, however it uses a K&N airfilter. From the comments over the years this doesn't seem to be the best type of airfilter in dusty conditions. Does the air filter and box need to be from the same manufacturer?
Does anyone have any experience with Fabwitz? https://fabwitz.com.au
Secondly, would the shape of the air intake make a difference? They have a round one and a slightly shaped on that costs slightly more.
Thirdly, they do an airbag, however it uses a K&N airfilter. From the comments over the years this doesn't seem to be the best type of airfilter in dusty conditions. Does the air filter and box need to be from the same manufacturer?
Is spending $1000 for a replacement air box a good investment? And do you actually need a snorkel?
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Skip the 'pod in box' type filter and get an airbox that uses a panel filter like Moonlight, PDI etc. Far better flow and the moonlight uses a paper Donaldson filter and PDI a genuine Toyota panel filter.
Thank you. Was in two minds whether to get the airbox too. Thank you for your recommendation. I do like the PDI airbox, which unfortunately is out of stock at the moment.
I made my own S-pipe. 3” to 3.25” to the factory lid. I have a wix filter minder and I think my air is restricted because at 16psi it already maxes out.
Turbo is a TD06SL2-18G
Factory airbox and safari snorkel
Brand new wix filter in it
I may try a Afe filter and see if things improve.
Only had the turbo on for 2 days already sent it in for RMA.
I’m starting to question of the air intake restriction is causing turbo over speed
Turbo is a TD06SL2-18G
Factory airbox and safari snorkel
Brand new wix filter in it
I may try a Afe filter and see if things improve.
Only had the turbo on for 2 days already sent it in for RMA.
I’m starting to question of the air intake restriction is causing turbo over speed
