IS200 + 2JZ-GTE + single turbo

[JohnA]

True, but the HKS was meant specifically for this engine (looking at the receipts of the power-seeking ex-owner) and in any case HKS paper filters are regarded as the best in this (sad) business, having the best (read: least compromised compared to stock) filtration.

 

I'm sure you could fit two (or three!?) pod filters there, but you'd still be far away from the stock setup.

 

Sorry to burst your bubble mate

 

(as for the 50x50metres theory, that would make it 50x100 x 50x 100 = 25 million cm2, which is a tad more )

[Ian C]

No bubbles burst here mate, I've got one of those huge K&N things on me single turbot, so as far as pod filters go it's huge (if currently unshielded Prototype shield has been made but proper one hasn't yet). However, your calculations are interesting, 5000cm2 is 50cm*100cm, that's a big mofo of a panel filter I guess if you unfold the filter it would be that big, but how does that help? Surely surface area is the cross-sectional area of the filter as it sits? Depends if you are talking about filtration or airflow I guess. Not sure what what angle you are approaching this from yet.

[JohnA]

No bubbles burst here mate, I've got one of those huge K&N things on me single turbot, so as far as pod filters go it's huge

I've used K&N pods myself --- on turbocharged bikes you haven't got much choice really, space is really tight and airboxes (or half-decent proportions) are science fitction.

 

But the Supra's airbox is not exactly undersized, and it is fed by two decently designed cold air intakes. So I'd be in no hurry to junk it if I were looking for more bhp.

 

(if currently unshielded Prototype shield has been made but proper one hasn't yet).

I've got a pic of a half-decent shielding on a supra engine somewhere on my website, under 'cooling' I think, I'll see if I can link it here

However, your calculations are interesting, 5000cm2 is 50cm*100cm, that's a big mofo of a panel filter

Yep, if you unfold it it's so much bigger (surface area) than the cone, that it's not funny.

I guess if you unfold the filter it would be that big, but how does that help? Surely surface area is the cross-sectional area of the filter as it sits?

Not exactly, the air molecules try to pass wherever they can, as fast as they can (at full boost they're sucked in real hard, at low/off boost the difference of a filter is trivial)

A large 'active' surface makes it a lot easier for molecules to pass, for a given filtration ability. Cone filters typically allow much larger dust particles through, that's why they get away with smaller dimensions.

But all that is just grit that slowly erodes the valve seats and the piston rings (and the compressor blades in extreme cases). If you do leakdown tests regularly you can see this clearly, it is very measurable.

Depends if you are talking about filtration or airflow I guess.

Both. Increasing one compromises the other.

 

Aftermarket 'performance' filter manufacturers don't have to adhere to any reliablity specs worth mentioning. So they don't give a crap if your engine goes from leakdown 5% down to 20% in 20K miles.

OEM filters cannot afford this sort of behaviour, or else warranty claims will go through the roof and second-hand values will eventually drop to nothing, damaging the Firm's goodwill (on the balance sheet, where it hurts!)

[JohnA]

here ya go

 

The filter is kinda small, but the sealing is fine, you get the idea...