Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Spray on Inside of Windscreen

Good question: I think it gets worse with speed but need to find out. Rain is forecast today so will go out this afternoon after work and see.

Clearly from what others have reported the way airflow varies from car to car so the dirtying if the inside of the screen is something of a random occurrence.

On Tarka the back deck of the car gets filthy as does the rear of the hod if it is up. The roof stays clean!

Yesterday I drove with the sun visors swung up so that they were almost vertical: going through a wet patch on the road it seemed as though they stopped the water getting on the screen, but not the mirror. This suggests the issue is more complex than I thought.

I’m going to try the rear mud flap route before doing anything else and then may see if fitting a spoiler along the top edge of the rack and see what the airflow is like along the top of the screen is doing, as has been suggested with woollen tufts.

I’m beginning to think that the presence or absence of crud on the inside of the screen is due to the interplay of two sets of turbulence, that from the flat screen and the vortex from the rear of the car. It is also worth note that the top of the box sections between seat and door get covered with road dust when driving; I cleaned and polished them last week and after a drive yesterday they were dull and gritty again.

So it is all rather difficult and the answer may well be a couple of micro fibre cloths and to enjoy driving, not worry about it.

Nick, I have also though the same: on the Plus 8 the reversing and red rear fog lights are simply attached to the flat bottom of the car. Hence my suspicion that the way the vortex comes up from the rear is important.

I'd love to get the car in a full sized wind tunnel!

I also want to compare the back end of a Roadster with a Plus 8 and see if the angle of the rear deck differs in any way, also the distance from base of screen to the edge between rear deck and underside.

IF it can be shown that the lack of curved under-body spoiler/diffuser is significant this could be a job for Cain!

My 2009 plus4 does it- I just thought it was because Irish rain was "thicker"!!!!

[i]

I'd love to get the car in a full sized wind tunnel!


Be very careful....;-) Many years ago when on the shop floor I went on a 'Crypton' engine analyser course, we had an all singing and dancing machine and one day we had a trade in Austin 7 that was running rough. Being early 20's and all keen I connected up the Cryptons multiple wires and the car refused to start. The service manager wandered over and said 'daft bugger, you have gone and scared it!'. All the other mechanics fell about when I disconnected the analyser and the damn thing fired up first time. So beware of putting your car in a wind tunnel, you may scare it and it might turn out to be the ultimate fastener test......I bet at least part of the car goes through the blades ;-).

BR
Colin

A good indication of car aerodynamics and how effective spoilers and wings are ,can be seen on the state of a rally car when it comes off the end of a gravel special stage.

It's a traditional Morgan (well in Peters case, nearly) so for heavens sake what's all the fuss about spray on the inside of the windscreen....never mind discussions re wind tunnels. If it's a huge issue can I suggest that you shouldn't be driving a Morgan!

That reminds me of a comment a builder in Dunghloe Co Donegal came out with after I wished him a good morning and said it's a bit damp this morning. "The clouds are a wee bit low this morning yes" it put a smile on my face thinking about it.
That was back in 1972 maybe it is pishing down nowadays.

Back to the thread John has nailed it, if you don't like the damp inside the car don't drive any Morgan in the wet.

Slightly more spray at speed from the air flowing over the top and this mainly on my head but more water dribbles up and over the screen top and runs down the screen inside. The air hitting the screen pushes it up.i often wear sunglasses to stop drips hitting my eyeballs too...but not at night!
It never stops me from driving but I will stop to put the hood up if really bad.
Towels are a permanent fixture in a Mog....
Water if it is raining and to mop up sweat if it's

Wind tunnel?
A Morgan is a brick......
If you want aerodynamics buy an Aero!
Take the windscreen off to gain 10mph speed and no air brake effect .

If you sit in the rain, YOU GET WET...