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240 Diesel Airbox

MSGGrunt

New member
Joined
Feb 13, 2018
Location
Western Massachusetts
Is the 240 diesel airbox the easiest, least modifications required airbox to be used when doing a turbo swap into a 240? Not a +T, but rather swapping in a whole B230FT out of a 940 if that matters. I only ask as I know these diesel boxes are less common and if it is the one that is the easiest to use I need to start searching for one sooner than later.

My research indicated that though people say a 740/840 airbox can work it requires a lot of melting, forming, modifying or a custom made bottom half that fits the 240 fender well and then still may have interference issues with the radiator and intercooler.

Also, Kjet "Cobra" airboxes can be used relatively easily with some modifications to the internals? Please correct me if this is incorrect.

I prefer as close to stock appearance as possible and, if given a choice, I like the looks of the square airbox out of the diesel over the roundish "cobra" airbox. The airbox out of the 940 would be "sexy" only because it says TURBO on it, but that's more esthetics than functionality.

I would be willing to run an open element cone filter, but would rather have something a little more OEM looking.

Advice..
 
The Diesel airbox is very easy to make work if you have one, or access. The 940 airbox flows enough air to support the HP goals for most of us, but requires a bit of massaging in order to fit.

The Kjet Cobra requires gutting of the fuel block and removal of a few part, but it will fit any 240 fender area.

I went with a cone on the end of the MAF.

Different strokes I suppose.
 
Diesel airbox won't work if using the stock 240 intercooler as the outlet of the airbox occupies the same space as the inlet of the intercooler. However, the diesel airbox will work if one is using the '92+ 940 intercooler as shown above.
 
Pardon my rookie questions I just want to do this right and be as painless and as OEM as possible even if it means ordering/sourcing new/used parts, ie radiator and intercooler.

1. Diesel airbox will not fit with OEM 240 turbo intercooler if I used an intercooler out of a 240T.

2. Diesel airbox will work with 940 intercooler, but 940 intercooler and radiator are not bolt in.

3. Kjet cobra airbox is the OEM airbox used on 240T and is a direct bolt in and will work with an intercooler from a 240T. With the internals of the Kjet airbox gutted.

Seems like a modified Kjet airbox used with an intercooler from a 240T would be the most bolt in option?

Does a 240T radiator provide enough cooling for the B230FT motor?
Does a 240T Intercooler work with the B230T motor?

I am not looking for mad HP initially, max future mods past just turning up the boost on the stock turbo would be larger turbo, larger injectors, and ECU chip. Whatever HP a stock radiator and intercooler can handle would be my limiting factor. I have not completely ruled out using the 940 radiator and intercooler that will come out of the donor car I just don't want something that looks hacked and was thinking OEM bolt in parts designed for the 240 chassis would ensure and OEM look/fitment.
 
Cobra airbox is bolt in and the least painless option imho (except cone filter on end of MAF)

Unless your car came with the Cobra airbox, you will have to drill 3 holes in the inner fender to mount it.

The stock radiator will be more than sufficient if it is in good working condition, Intercoolers don't care what they are attached to, as long as it doesn't leak, and you can plumb it, run it.
 
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Cobra/Kjet are one and the same no? The bottom being the airbox and the top being what is referred to as the "cobra" See picture.

And use a used intercooler out of a 240T. Are the radiators different in the 240T than a NA 240? I have no problem buying a new, correct radiator if I have to, but see that the 240T intercoolers are NLA.
 

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If this is the bottom of what is referred to as the Kjet airbox I would have no issues drilling the necessary holes in the fender to mount it. If anyone reading this knows of where I can get a complete assembly please PM me.
 

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Buy my D-jet airbox?

140D-jetAirBox1.jpg
 
D-Jet? I can't see the picture. Is this a diesel box or a K-jet with a missed key stroke? Ideally I would like to buy a whole K-jet assembly as pictured above. This will be pared with an OEM 240T intercooler and OEM 240 radiator.
 
Thanks. I think I have only seen the ribbed kind like in the picture.

It goes inside the snorkel. There's a hard pipe that fits inside the snorkel and a cross piece that supports it from the inside. Non-IC 240t's didn't get those pieces.

Option 2 is do the "group a" style. Just make a plate and a hard pipe to go to the bottom half of the airbox.
 
I did think of the "group a" style after seeing a picture of someone who built something similar. If I can get my hands on only the bottom part of the K-jet airbox I would have no problem building something similar myself, though I would probably coat the aluminum in black to make it stand out less and look more congruent with the rest of the black plastic airbox.
 
Here's some additional pictures showing the cobra reinforcement (tight fitting aluminum pre-heat hose inside the rubber), the teepee support frame to prevent collapse, mounting holes, and some other details. (The gutted K-Jet distributor came from Pat -- I couldn't bring myself to destroy a working one.) Click on pics for fullsize.

 
This helps immensely. In a perfect world someone would have an extra complete airbox and accessories as shown they would be willing to part with. I can see why, for simplicity reasons, people use an open air cone filter. I may be forced to do just this until I can piece together all the parts as pictured above.
 
D-Jet? I can't see the picture. Is this a diesel box or a K-jet with a missed key stroke? Ideally I would like to buy a whole K-jet assembly as pictured above. This will be pared with an OEM 240T intercooler and OEM 240 radiator.

Nope it's D-jet basically plug and play complete with a giant filter.

D-jet%20Airbox%201_zpsx6zhmwhr.jpg
 
for those who are +T-ing a street car. what are good options for relocating the washer fluid reservoir if using either D- or K-jet airboxes?
 
I was thinking for my build the easiest could possibly be a bag like this rear windshield washer reservoir/bag that is used in FJ60 series Toyota Landcruisers. Granted it doesn't hold anywhere near as much as a stock reservoir, but should be pretty easy to tuck just about anywhere. And I could live with just refilling it more often. Just my idea.
 

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