Van's RV fiberglass snorkel for intake for Bearhawk 4?

[Big_Rocks]

Hello Everyone,

Curious if anyone out there has used a Van's fiberglass snorkel for their induction? If so, was there clearance/fitment issues? Would like to see some pictures if anyone has any.

Thank you in advance Kyle

[jaredyates]

There have been a few of us that used the FAB that mounts under the carb, is that the same thing?

[Big_Rocks]

From what I gather it is different than the filtered air box. Its a cold air intake plenum on RV aircraft incorporating forward mounted Bendix fuel injection.

Use can see a few pics of install here:

http://jasonbeaver.com/rv7/2013/01/02/installed-snorkel/

You can see it on the vans website.

https://store.vansaircraft.com/va-132-2-fiberglass-io-engine-snorkel-va-132-2.html

[Battson]

I fabricated a custom setup, not the same as that, for our IO-540.

I would advocate for considering airflow volumes and pressures though, with any setup. If you can get ram air there's free horsepower to be had, or vice versa if you restrict the intake the you could lose horsepower. Especially if you're using a larger engine - as it appears to be designed for an IO-360 - and it's certainly not going to win any prizes for the lowest air restriction / pressure loss induction system.

[Untainted123]

How do the IO-540 RV-10 guys do it? Is there a different one than the one for IO-360/390? I haven't worked on a lot of RV-10's to recall how the IO-540 breathes, but maybe the setup could be adapted. On my 4 place, O-540 (not injected), I have the Van's FAB bolted to my carb, and I have the Van snorkel from the bottom of what would be an RV-10 cowl, with nut plates holding it onto my metal lower cowl. Works well.

[svyolo]

I did something similar. I used the FAB, and made my own snorkel. Mixed results so far. Also 540. How is your MAP? How high can you keep 24"?

[Mark Dickens]

The Vans snorkel is surprisingly efficient. There are many discussions about that on the VAF website. It's been flow bench tested as well. I would not hesitate to use it on an IO-360/390 since that's what it was designed for, BUT interfacing it with the nose bowl and the baffles is another question and considering the considerable cost of buying one to explore that is a risk you would have to take. Since I am using the IO-360 with the forward facing sump, I can't use the standard chin scoop, so I will probably reprise what I did on my RV-8, which was to fashion a ram air intake straight into a modified Spectre air box, but I'm just getting started on that.

[Battson]

Yes, I wouldn't want to comment on the "efficiency" of the snorkel, as far as snorkels go. I am sure it's been optimised to a high degree. I would note that efficiency is not a universally defined engineering metric though, and there are many interpretations, so care is required when discussing how "efficient" something is.

However, I am equally sure a snorkel (not matter how good) offers very little ram air effect - probably none. It's more likely slight suction occurs (albeit, quite efficiently).

The Bearhawk has ample room in the cowl, it's one of the strong points of the design. This allows lots of options for inductions.

I was very interested in an induction just like this snorkel some 14 years ago when I was building our 4-place with the IO-540. In hindsight, I am glad I didn't go that way (it was mostly luck). We ended up with positive pressure and a ram air intake, we see near 30"Hg at takeoff around 200ft above sea level, passing 40 KIAS, meaning we are getting 1 - 2 inches of ram air effect. From memory this creates quite a lot of free horsepower (depending on the day) during the critical takeoff and climb phases, just because of the induction design. Possibly as much as 15hp for free, on a good day, but I could have misremembered that.

[Mark Dickens]

I do have an uninstalled VA-132-3 snorkel since the engine for my RV-14 hasn't arrived yet, so I will see if I can fit it in the Companion cowl and report back. If I can, that's the way I'll go...

[Bcone1381]

Do you need a prop extension to push forward the nose bowl accommodate the snorkle?

[Mark Dickens]

I clamped my VA-132-3 snorkel onto my injector (RSA-5) and I was very pleased with how it all fit. I wasn't able to remount the nose bowl, but I feel confident that there wouldn't be any issues with interference with the forward or bottom area of the nose bowl, but there would be an area which would have to be trimmed back where the snorkel interfaces to the baffle. See below where I've outlined in red.

All in all, I feel good about this option. It may not be an ultimate ram air solution, but it's a good fit AND accommodates Vans alternate air door set up.

And by the way, here is another ram air option which I haven't really vetted but might work with a blister molded onto the nose bowl: https://hpaircraftblog.wordpress.com/ram-air-intake/

IMG_2292.jpg

IMG_2291.jpg

[Nev]

And by the way, here is another ram air option which I haven't really vetted but might work with a blister molded onto the nose bowl: https://hpaircraftblog.wordpress.com/ram-air-intake/

I love the "outta-the-box" thinking with this. Unfiltered ram air - Brilliant!

[Mark Dickens]

I love the "outta-the-box" thinking with this. Unfiltered ram air - Brilliant!

This is actually an improvement on an older ram air setup marketed several years ago by Rod Bowers, since deceased. The Bowers approach was to use reed vanes inside the filter enclosure for filtered non-RAM air and use the open butterfly valve for the unfiltered RAM air. The negative on the Bowers approach was that non-RAM air was sucked from inside the cowling. See https://vansairforce.net/threads/rod...-system.44018/ for more on that. I used some of Rod's parts on my RV-8 build, basically the scoop and bell mouth

20180723_072047.jpg

[Big_Rocks]

Some great discussion here!

Thank you Mark for taking the time try the snorkel on the Companion. I have the RSA 5 to go with the IO-360 I have but don't have it mounted yet, another great option if it basically fits as is. Do you mind me asking which sump is on your motor? Looks like A1B6 sump but can't really see.

Nice work on your intake Battson. Do you think that you are seeing RAM air benefit as low 40 KIAS? That would awesome if so! From reading through the VAF threads seems like definitely benefit when you pass the >100 KNT threshold.

I am not really set on any particular intake at this point but I do like the idea of making it as efficient as possible and thus the RAM air idea are intriguing.

[Mark Dickens]

Some great discussion here!

Thank you Mark for taking the time try the snorkel on the Companion. I have the RSA 5 to go with the IO-360 I have but don't have it mounted yet, another great option if it basically fits as is. Do you mind me asking which sump is on your motor? Looks like A1B6 sump but can't really see.

I have no idea. When I asked Bob Barrows about the provenance of the engine, his response was "why do you want to know that"?

After having less than pleasant words with him about how to properly respond to a customer, he allowed that he didn't really know, but it might have been a A1A...who knows? It was "built with parts".