A potentially stupid snorkel idea it's time to actually consider...

kennith

Well-known member
Apr 22, 2004
10,406
101
North Carolina
I've never really liked all the extra tubing, sharp bends, and overall restriction added by a snorkel.

In the past, I've thought that removing or relocating the ABS modulator to the factory air filter location would give me room to have short intake with an in-line air filter in almost a straight shot, full throttle body diameter, right to a single bend up the A pillar. Now, it may require more body work than a Mantec or similar, and perhaps even some material removed from the hood (possibly not, if I let it dip a bit) but it makes more sense to see if it's even possible first.

The sticking point for the intake itself is just how closely a MAFS, throttle body, and air filter can be in relation to one another. It's still going to measure airflow, but it'll be hotter and closer to the residue that ends up collecting around the throttle body. Also, the air filter will be much closer to that area. This is all assuming the space makes it possible.

I haven't really seen anything mentioning the drawbacks or potential failures associated with a MAFS that close to the throttle body. I know they don't like contamination at all. I suppose the possibility is there for a small power increase, but the objective is really to avoid a drop in power and intake efficiency.

There's also the issue of relocating that modulator. That's a lot of brake tubing, but so long as it's hard I don't see an issue. If it's removed entirely, it becomes a different problem. Then there's keeping rain out of it, but there are a few ways to mitigate that; it's worth actually building a test setup to be sure, but it should be possible.

What about that MAFS and filter being so close to each other and the engine, though; and more directly exposed to the heads and exhaust manifolds? Heat shields are obvious, but that doesn't change the issue of contamination and overall temperature in the area.

If it's possible and probably reliable, I'd essentially have a "one bend" cold intake solution, rather than a "six bend" solution with three 90s in the mix and a corrugated section as well. Seems to me it would eliminate quite a few drawbacks if possible.

Cheers,

Kennith
 

kennith

Well-known member
Apr 22, 2004
10,406
101
North Carolina
Why do you want a snorkel in the first place?
They are very useful for long, dusty roads and certainly for a bit of extra security in fording. With a pre-filter up top they get even better, but that's asking a lot with all those bends in the tubes.

I've had three for this vehicle over time, but never really liked the restriction on any of them; and it all comes down to how the intake is routed. It's very noticeable at high RPMs, and that's why they're not installed if I'm not using them. I'd rather just have something that doesn't add the restriction in the first place.

Cheers,

Kennith
 
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robertf

Well-known member
Jan 22, 2006
4,006
25
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That intake tract is resonance tuned to work with the displacement and manifold. One of the few technological advances BMW dumped into the rv8.

The maf transfer table or whatever bosch used is done in reference to the post filter duct behavior

any pumping loses youll reduce at a specific rpm will likely be detrimental to other parts of the powerband. The engine management will also be relying on feedback corrections to account for MAF errors.

I wouldnt do this, but Im told I dont have a fucking clue what Im talking about when it comes to thermal efficiency
 

kennith

Well-known member
Apr 22, 2004
10,406
101
North Carolina
That intake tract is resonance tuned to work with the displacement and manifold. One of the few technological advances BMW dumped into the rv8.

The maf transfer table or whatever bosch used is done in reference to the post filter duct behavior

any pumping loses youll reduce at a specific rpm will likely be detrimental to other parts of the powerband. The engine management will also be relying on feedback corrections to account for MAF errors.

I wouldnt do this, but Im told I dont have a fucking clue what Im talking about when it comes to thermal efficiency
That's all part of my concern. I don't know how the system will react to the modification, and I don't know if a MAFS can hold up reliably in that location or if fouling would be a problem. Even if the system has the difference in tune covered, the sensor is still much closer to the exhaust manifold.

It may be possible to match the tuning, to a point. There might actually be enough room to replicate the length. It doesn't actually have to improve upon factory airflow; only on factory airflow with a snorkel attached. I'd be asking a tuner shop to handle the details, there. Come to think of it... I should just let them have a look.

I don't know why I didn't consider that before. All the answers might be available at once.

What you said about the engine in that thread was not incorrect, it was simply irrelevant; and incomparable to my contention in regard to a diesel. The actual attempt to compare the two as a slight was pointless. Your mechanical skill wasn't on that particular table so much as your logical application of it in diagnosis.

Cheers,

Kennith
 

_ExpeditionMan

Well-known member
Dec 11, 2017
52
2
Fort Worth, TX
Why not retrofit the defender setup for an under hood snorkel? It won't run up the A pillar but will still raise the intake and you can keep an OE setup. You also won't have to worry about water splashing through that headlamp housing right into the airbox.
 

ukoffroad

Well-known member
Jan 13, 2010
1,588
38
Lynchburg, Va
I have one waiting to go on, but I am going to cut up an old spare fender and try it with that before committing, so if it has any detrimental affect I can just put the orginal fender on and put it back to normal.
 

pdxrovermech

Well-known member
Jul 3, 2009
1,675
6
Portland, OR
haven't tried the MAFS relocation on a rover setup, but when I initially installed an LS3 into a RRC I ran into problems with the MAFS being too close to the intake. Kept throwing codes and had running issues. Had to ultimately move it farther away to fix the problem as per what my Chevy experts told me.
 

kennith

Well-known member
Apr 22, 2004
10,406
101
North Carolina
Why not retrofit the defender setup for an under hood snorkel? It won't run up the A pillar but will still raise the intake and you can keep an OE setup. You also won't have to worry about water splashing through that headlamp housing right into the airbox.
I've got a DII, which already does have a relatively high air intake in the engine bay; just not quite as high as I'd like. It's a pretty good design, actually, until you bolt a straw to the end of it that has to fit in the limited space under the fender. I also like collecting the air as "outside" of the engine compartment as possible; another area in which the DII intake system is actually pretty decent.

The ARB "Safari" unit , while visually divisive, seems to be the best option off the rack so far as airflow is concerned; but I still like that straight tube idea. If it doesn't work out, I'll just end up with the Safari I think, and sell the Mantec. This is really an area where a project like this could actually be of benefit, though.

Cheers,

Kennith
 

kennith

Well-known member
Apr 22, 2004
10,406
101
North Carolina
haven't tried the MAFS relocation on a rover setup, but when I initially installed an LS3 into a RRC I ran into problems with the MAFS being too close to the intake. Kept throwing codes and had running issues. Had to ultimately move it farther away to fix the problem as per what my Chevy experts told me.
Cool. I needed to hear that; it's just the sort of feedback that I'm after.

I expect that will be the case, and if indeed it is, I'd have to add some bends to replicate the length. That's beyond my fabrication capacity, though, and if I were to go that route, as noted, I'd just hit up a shop that specializes in turbos for small engine compartments.

They'd be able to figure out the tubing issues and do a much nicer job than I ever could. I can't weld for shit.

Cheers,

Kennith