I seem to remember a past thread where someone had done real-world 'wool tuft' airflow pics out on the road and air was going in and not going in surprisingly strangely.
Possibly this one ?
Not wishing to undermine the efforts of an enthusiastic amateur here, but I'm not really sure what that video proves? I'm also certain any student aerodynamics would pull it apart in seconds, and such efforts would be certain to have the Godfather's of this science Malcolm Sayer and Frank Costin rolling in their graves
I'd like to read the full report as to me the wool tufts don't seem to be telling us much, if anything at all, and without understanding what’s also going on inside the engine bay the data is double useless. Heaven only knows what’s going on as air passes beneath the car as it’s really aerodynamically messy under there, let alone what happens when the air gets trapped inside the sail like front wings of a Trad Morgan?
I can however accept there will be a potential for a high pressure zone in front of the screen, you don’t really need a degree in aerodynamics or run any tests to predict that one, just take a ride on a motorcycle over 60mph and tell be what you learnt. However, air often behaves in mysterious ways, for example as the air gets stopped by the very vertical screen and then tumbles, the roll could easily create the opposite effect of negative pressure at a certain point that remained unmeasured in the video. The datum points in the test simply aren’t tightly enough packed or comprehensive enough to understand what's going on everywhere, the louvres on the test car's bonnet sides also appear to be 'Outs' not 'Ins', so that throws any data out for my application anyway.
Finally, because we have no real idea what's genuinely going on under the car, inside the wing voids, and especially within the engine bay, I really can't see what we are meant to be learning from this video? I don't mean to flame the attempts of an enthusiastic amateur, but as we all know 'part data is often worse than none at all'. So, despite the valiant attempt I’m calling this video out as 'Null & Void' in terms of usable data, there are simply too many questions unanswered, indeed for me it actually raises more questions than it answers.
One thing we should all accept is that a Morgan has very poor aerodynamics, but let’s be honest here none of us bought a Morgan for its slippery shape, we bought it for its classic flowing lines that are pleasing our eyes, and personally I take great pleasure in ripping past modern cars driven by Joe Public and young lads with their baseball caps on backwards who have no idea what they see as a relic could have such a surprising turn of speed.
Anyway chaps, my own fuel economy and engine load analysis also proves the effects of poor aerodynamics only really start to ramp up aggressively over 70mph, I've proved I can hold 80hph in Monty and still deliver 38mpg by running 39 BTDC and a 15.5:1 AFR, obviously the 900kg mass plays its part here as does the super highly efficient breathing and very low pumping losses of the excellent 2.0 Duratec engine, you just need to un-strangle the poor thing by removing all the emissions junk.
As part of these tests, I've also logged IAT (intake air temp) data that proves there's very little difference between the Mondeo airbox and my open element filter mounted just forward of the heater intake, indeed if we exclude idle and take our data from just 15mph and above, my open AEM Dryflow filter delivers lower IATs than those recorded with the Mondeo airbox recorded at the same road speeds. I would also argue by far the biggest improvement available to us all if we want to lower out IATs and increase the density of the incoming charge, is to stop pumping superheated exhaust gasses directly into the inlet manifold (exhaust gas recirculation).
On other projects I've directly recorded EGTs (exhaust gas temps) as part of my tuning data set, and what you see is typically somewhere between 900–1300°F at the header. This will vary depending on inlet port length, engine load/cylinder pressures and ignition angle, but believe me even at their coldest exhaust gasses are super-hot, so the impact EGR has on IATs is massive and way more than any open filter that doesn’t actually have any impact in my Morgan above 15mph anyway.
If you want to increase the density of your incoming charge and fill your Plus 4's lungs with a nice cool and pure mix of lovely air an fuel, all you need to do is fit a Duratec ERG delete kit. If at the same time you delete the stupid 'Swirl Flaps' you'll likely pick up the easiest and cheapest 10hp you'll ever add to your Duratec Plus 4 Morgan, a £10.00 ERG blanking plate and an afternoon removing the plastic inlet manifold is all it takes.
