airflow question/picture request idi

[jhax]

Hello Everyone,

Picking up my new to me 86 golf westy diesel on saturday and I have a question. I am not looking for uber amounts of power or anything and i am in the process of building an ALH TDI monster for the car over the next couple of years and until then i know airflow is the best thing for the little IDIs. Has anyone just cut (very cruel way of putting it) a hole in the top of the hood right above the airbox and formed a plastic housing that creates a seal around the hole? Is rain water ever a problem with this? Please dont burn me im not new to the car scene nor the VW mk2 scene i am just curious as to if this is a better option than running a pipe or hose from the airbox to the fender.


Here is the little car sitting on a little lot in OKC

And here is n example of the cut (i hate using that word) in question.


Any input or images would be appreciated.

Excited to finally have a MK2 diesel golf.

Justin

[ORCoaster]

You sure that hood opening goes to the airbox and not to the interior venting?  The owner deleted all the stock vent grills and did a single wiper install so I am thinking he vented that opening to the existing rain tray and is not incurring water into the engine.  It may work as you say but as i watch the rain crawl up the hood of my car I would question that particular set up.  I might turn it around as the windshield actually creates a heck of a lot of pressure when moving forward.  That is why you get air thru the vents at 60 without the fan on.  Grabbing air out of the raintray might be just as good or better than through a tube up front. 

Any takers on that one?

DAS

[jhax]

yeah kind of like an inverse cowl the wind vortecies flow backward under the hood and into the air box. any other input or design pictures would be great!

[CRSMP5]

rain bad... takes very little liquid to bend a rod... yes ive bent one in a small goofy river of water vs the lakes i hit way before that... filter got saturated vis lakes... the small flow 1/4 mile from home killed it..

[jhax]

bummer dude. so stick with the dryer hose. winkie face

[burn_your_money]

Grabbing air out of the raintray might be just as good or better than through a tube up front. 

You'd probably be deaf within a week or two

[ORCoaster]

I'm deaf now, just ask the wife.  I drive a diesel what more do I need to say. 

Is he calling you winkie face?  or adding that to his post like this?   

[jhax]

the ladder, i choose the break away from the norm of the stupid emoticon bull and write out the emoticons i seem fit. i.e. smiley face, one eyebrow raised face, angry face

[ORCoaster]

Interesting bit of nuance,  got a location? 

[JamesT]

The idi intake has some small drain holes in the bottom, the actual intake runners are only open in the top quarter of the housing.
If you opened up the drains a bit (and filtered them) the rain water may not be a problem. Are you hoping for a ram effect, or just for a clean, simple source of cool air? If the former, you may be doing more harm than good: just cutting a vent in a hood may not create a high pressure space and may actually create a low-pressure zone. If the latter, what's wrong with a bit of hose running to the stock hole in the passenger fender? If it's a clean engine bay issue, just make it a solid pipe and shiny.