Lotus Europa 16V Gordini

[BDA]

That's a really big radiator! Are you using a thermostat? If not, you might want to consider one. Of course, a smaller radiator is always an (expensive) option.

Good luck!

[dakazman]

  Congratulations Mecky,
 Nice figures at the dyno.  Maybe now you’ll take center position on the podium. Your car is amazing inside and out.
Dakazman
Dave Kaczmarek 😉

[Mecky]

Thanks for your nice feedback, boys. I'm using no thermostat, but an electronic temperture controller. It's switches the water pump off in intervals, until water temp reaches target temp minus 5 degrees. But the radiator is still too big for that in this configuration. But next year, I'll make it will work.

This is what I do in the moment: getting rid of the old useless ducts and install type 47 NACA ducts to deliver air into the engine bay.

[dakazman]

   Nice work Mecky
 when and if I get my crossflow assembled this may be my first mod.
dakazman

[jbcollier]

They "work" but they don't let in that much air.  For example, one alone won't supply enough air for the engine air intake.

[GavinT]

I bought a pair of the 47 style ducts from a mate some time ago.
I believe they're the Banks ones.

I've calculated the area where the duct empties into the interior at ~ 5785 sq MM.
For reference, the area of a 3 inch (internal) trunking system is 4560 sq MM.

My objective was to essentially isolate the engine intake from the hot engine compartment so I reckon that should work. The left side duct would just be to help ventilate the engine bay . . hopefully.

There's probably also some proviso's.
The last time I researched submerged ducts, the theory calls for flat surrounds for the ducts and the internal walls of the ducts are supposed to be sharp and at right angles to the duct base. The Banks ducts don't conform to these specifics and I have no idea how much difference that makes.
Perhaps that's only important for an aircraft travelling at 600 MPH where some engineer has specified minimum air flow parameter?

[jbcollier]

One lister ducted his carbs to a 47 type NACA duct.  When driving his carbs were starving for air and he had to disconnect it.  Be nice if it worked.  Heck, I'd cheerfully put in a pair.  But it doesn't, at least, not that much.  By all means put them in.  Just keep your expectations low.

Modern mid-engined vehicles have air "scoops" that really push the air in.  I've been scratching my head on this one for a while.  No easy, aesthetically pleasing solutions so far.  Currently I'm thinking of a scoop/snorkle up right behind the driver so it doesn't affect the rear view.  Not sure yet.

[GavinT]

Yeah, that maybe, JB.
Can you recall who the lister was?

Mecky's duct looks to be the same as mine. It appears he's removed the panel section which incorporates the fuel filler because he already has that sorted.
Perhaps it's difficult to see in the matt grey primer of Mecky's duct, but the upper long wall rises above the surrounds slightly. The lower long wall isn't at right angles to the submerged 'base' of the duct.

It seems to me there's many variations of these ducts. As we know, not all 47's had ducts. Some 47's have two vertical sides and some have rounded corners on the rear edge. Perplexing.

If I recall, Roddy's ducts are different again and have the slightly proud ridge continuing around the rear edge of the duct, but with both sides at right angles to the base. My initial speculation was that these differences in ducts are perhaps to aid water shedding on a road car, but that doesn't really make sense, either.

But I agree it's best to keep expectations in check.
I have no way of testing any of this so my reasoning has come down to the basics. If we ignore any 'ducting' ability and merely concentrate on the available intake area, they should be adequate, right? That presumes 3 inch diameter trunking is adequate.

I like the snorkel idea but I don't see any way to get the aesthetics right . . at least for me.
I'd also expect a snorkel would have lots of throughput and effectively pressurise the air box at speed if intimately connected. That could play havoc with the tune and I never figured out how to counter that.

[Dan C 2624R]

To add to the conversation, take a look at what Lou D just posted in the Random Sighting section.
Just so happens to be another Type 47 with Engine bay scoops.  Not NACA, I think but adding to the conversation.

Dan

[jbcollier]

Exactly Gavin, I can't see any snorkel being aesthetically pleasing either.  Right now I have my air intake ducted down to pick up cool air from low down in the engine compartment.

[SwiftDB4]

Yeah, that maybe, JB.
Can you recall who the lister was?

That was me. I hooked up 3" hose from my Banks NACA duct to my sealed carb box (twin 45DCOE's feeding a Zetec). Tested on a track day power was down drastically from no ducting and individual air horns with foam socks.
NACA ducts are only effective if they're in the airstream. That far back on the body they actually get less airflow at speed.
Installed 47 style snorkel with sealed connection to air box. 500 rpm more in top gear on track day.
I agree snorkels are not aesthetically pleasing. I only use my snorkel for track days.

[gideon]

I thought this was a pleasing implementation of air scoops for a Europa.  The photos are from the Facebook group.

[jbcollier]

They will function great.

Aesthetically pleasing?  Eye of the beholder I guess.  Doesn't work for my eye. YMMV

[GavinT]

Many thanks for chiming in, Swift.
More data is always good.

Reckon some of these ducts are bigger than others, too.

[Mecky]

They "work" but they don't let in that much air.  For example, one alone won't supply enough air for the engine air intake.

I think everything will be a step up from where I started. The old ducts just guided air into a the bodywork above the wheel arches. Thus, they were air brakes and did not deliver air into the engine bay.
I think the type 47 NACA ducts will improve fresh air situation in my engine bay. They will not bring any power improvement. But it may get rid of some heat from the exhaust, thus maybe the air sucked in by the carbs is a little bit cooler.