When I bought my car, it did not have a rain tray installed on the engine bay cover. I was going to buy one, but now I'm building a 2366 and want to do everything I can to keep it cool. Are there any cooling benefits to not having a rain tray? If I don't add one, how do I stop water from getting in the engine?

A few tests were done years ago by a member, I recall there was not a enough difference to take it out and then deal with all the rainfall.

It’s also a carwash tray…

Don't drive in rain.

That was more of my concern. I don't plan on driving it in the rain, just don't want to get water in the engine while washing or during a spring pop-up shower, etc.

Mine is garaged, and what I do is dust it off, get a bucket of water and rag. I've had my 914 for 7 years now, and its never seen a hose. Saves precious water also.

I actually tried this this past summer, just to see for myself. I've got a 4 channel digital CHT gauge in my car with sensors under each spark plug so that I can monitor all 4 head temps in real time. There was no difference in temps whatsoever between running with or without the rain tray.

I keep it on. I don't drive in the rain, but there's a surprising amount of stuff out there (leaves, bugs, etc) that'll fall into your engine bay without it. What annoys me are the little side vents on either side of the engine lid, neither of which have a rain tray. So water gets all over the battery on one side. It baffles me why Porsche would place the battery in a spot where it would come into direct contact with water. It's literally right behind the rain gutter on the roof, so at speed you'd be just pouring water right into that open vent and onto the battery. It seems like a poor design to me...really the only thing about the 914 that I don't like. No other air-cooled Porsche or VW has the battery in a spot where water would get dumped right on it. It makes washing the car kind of annoying. Does anyone know why they put it there?

Cars, including Porsches, were designed to be driven in the rain. However, waterfalls, floods and hurricanes are a little more tricky. Other than minimizing rust and corrosion, let's not get too OCD about your daily/weekend driver.

Certain Optima batteries don't fit under the rain tray....

Nor do the air cleaners on the original 914-6...

--DD

Since the 914 design on engine grill is pretty much an open area, is there a real problem when water gets in there and soak the engine with water? for carb and Fuel injection. I know there is a lot of places inside engine bay that water can drain but still water get all over the engine.

Majority of us try to avoid getting our car soak with rain but sometimes we really can't avoid the rain like here in SoCal. Sometimes it is sunny but suddenly a rain will fall.

Eric Shea's last drive from west to east experienced a hard rain but he was able to drove it without any issues.

I think the bigger potential issue is with the electrical connections. If all the connections are insulated and no wiring is exposed, you should be fine. I got caught in a massive downpour on the interstate in my old '72. That car had FI and no rain tray. But I could see the water coming off the roof gutters like two waterspouts in my rear view mirror right onto the engine grill. The entire engine bay got soaked and I had no problems.
That car also had holes in the floors and wheel wells, and water was getting flung into the car from everywhere!

I just don't understand why they would put the battery right where it can get wet, and in turn spill acid onto a structural frame component. Didn't all the other air-cooled Porsches have the battery up front?

Mine is off in the summer and on when the rains Start. However it's bulky an makes working under the hood tight. Why not a smaller lighter tray? Or a clip on light weight tray? Anyone making one?

I don't run one. I don't drive in the rain, I cover the engine when washing.
I think one benefit is heat dispersion after you stop or while driving in traffic. I also like the extra couple inches you gain for working on the engine with it off. Yes I know you can remove the whole lid in a minute.

I will probably put it back on some day, but no real hurry.

My six has lived its whole life with out one...

Just curious what engine config that you tested and what was the ambient temp?



I run without it during the Summer. It does.t rain here but where you are.......might need an Ark right now forget the teener.

I just stuck mine back on. I guess I better find the funnels and rig up some hoses. It dawns on me too that the front cowl drain box
better go back in as well.

Does anybody have suggestions for the hose?

Crap, did someone say El Niño?

I have plenty of funnels. Go to Lowes or Home Depot to the garden section and buy a 20 foot section of orrigation hose. I will trade you the funnels or the hose. Remember the swap neet is this Sunday.

2270 with dual Dell DRLA40's. External oil cooler. Ambient temps were anywhere from the 80's to the high 90's, with high Raleigh, NC humidity.

I ran with the rain tray on all year through the end of July. I took it off in August to do some tuning work on the Dells, and left it off for the rest of the month to see if my temps would be any different out of curiosity. They weren't so I put it back on. I always ran in the low 300's while cruising, and mid 300's on hills (for CH #3).
It makes zero difference to run with or without it, whether you're cruising backroads or sitting in traffic. At least on my car.

I also find that ambient temps make no difference to my head temps, except for the amount of time it takes for my engine to get to operating temp. Whether it's the dead heat of summer or the bone chill of winter, the operating temps are always the same.

The only thing that matters is knowing how to drive an air-cooled car, and how to use your rpm speed to keep the engine cool. Keep the revs between 3K and 4K when cruising, downshift when you hit a hill, and you'll be fine every time. I will say, I highly recommend that everyone who drives an air-cooled car get a digital CHT gauge. I've learned more about how to drive these engines in the last 10 months that I've owned this car, than in the many years I previously spent driving air-cooled cars.

BTW, this is the CHT gauge I have: http://www.mglavionics.com/TC2.pdf

2015, 05:49 PM' post='2248091']
I just stuck mine back on. I guess I better find the funnels and rig up some hoses. It dawns on me too that the front cowl drain box
better go back in as well.

Does anybody have suggestions for the hose?

1 inch pond tubing. Works like a champ: http://www.amazon.com/TetraPond-Pond-Tubin...t/dp/B004YK5HAK

The battery is located there in attempt to offset the weight of the driver and keep balance.

Guess I'm confused about the worries of getting the engine wet? The 6's have open grilles, my 911 dumps water through the tail onto the engine, my Elise's engine gets soaked in rain and car washes as it sets under large louvers, my Suby pulls water through the hood scoop onto the intercooler then down on the engine. Many other cars I've owned wind up with a wet engine driving in the rain.

My rain tray is out as it reduced idle temps while stuck in traffic during the summer, plus I like the look of seeing the engine through the grille. Between carb rain hats, decent plug wires, and a bit of silicone grease around the base of the dizzy cap, no issues with rain or car washing.

I'm not professing to remove your rain tray, just not sure why people feel it's bad to get the engine wet?

It's not the engine getting wet that worries me, it's the battery. Which is why I still don't get why they put it right under the side grill vent opening.

What setup are you running? As I said, I had no difference in idle or cruising temps with or without the tray, even in the dead heat of summer.

My next project is going to be to fabricate a lightweight tray with appropriately located drain holes to meet the stock funnels. If successful, I will either find a source for a vacuum formed replication process / or simply rebuild others if cost feasible and a demand arises.

My concept is to have four or more clips (like the 993's undercarriage drip pans) so that it secure when in use but can easily come off and be stored until, on the rare occasion, one or two rain clouds pass over SoCal, scaring the crap out of everyone here not from Louisiana...

I also agree with solving the side vent intake areas as well / have to think about that as I get closer to a workable solution.

See you guys at the BS Swap Meet on the 11th..... Hmmmmm BS Swap Meet (Bruce Stone) ........has a ring to it, doesn't it Elliot?....

Sorry, I should have more specific. I don't have a CHT gauge, but it's on my list...

I'm running a 2056, dual Webers, stock oil cooler.

Prior moving away from the traffic mess, I used to have a six mile stretch that was a 1st-2nd gear crawl, generally took 25-30 minutes to get through it. On those occasional days of taking the teener to work and crawling through this stretch, if air temps were 85-90 I'd see the oil running perhaps 5 deg warmer with the rain tray removed, but no discernible difference once moving.

I did notice a cooler engine compartment while sitting and idling - based on non-scientific experiments I observed the engine bay staying 10-15 deg cooler w/o the rain tray based on idling, but no measurements in stop-and-go traffic or while underway, but assume there would be enough airflow to minimize any difference once constantly moving.

So yes, slightly cooler temps in stop-and-go traffic but nothing really notable.

Understand about your concerns regarding the battery, which as we all know was a poor design. I used to run Optima Red Tops, but after several issues, I plan on moving to an Odyssey soon.

Ah, gotcha. I've got a remote oil cooler with electric fans so my oil temp tends to stay put unless I'm beating the crap out of the car. Not sure how the tray would affect oil temps with a stock cooler.

Yeah, that's the reason I haven't made the move to Optimas, after reading several threads about issues with them. What's the word on the odyssey battery? I haven't heard of it. Do they have the same issues as the optimal? It would do my mind much ease to be able to move away from an acid battery.