There's another issue for those of us who live in places like the northeastern US. Our rain isn't just water, it's polluted water--acid rain. Acid rain isn't good for the undercarriage, many parts of which are not galvanized. It's also terrible for the paint. As I understand it, our older cars don't have clearcoat layers on top of the colored paints, so the acid rain can ruin the paint over time. That said, the lack of clearcoat is one of the reasons the finishes on old Porsches look so good.

I don't worry about it if I'm out and it rains unexpectedly, or if I'm away on a trip in it and it rains, but if rain is likely I won't bother to take the car out for a pleasure drive, or take it on a longish drive that I'd use it for on a nice day. That's what the daily driver is for.

All well and good, but if you happen to have one lousy piece of grit somewhere on the finish that simply decides to disagree with all the reasons you don't need lots of water, you can wind up with some very deep and interesting scratches.
Ask me how I know

Back in the '50's I used to watch my Uncle Joe "wash" his newly painted cars at his body shop using just a bucket of clean water and a sponge. Would rinse all the grit off the sponge, then squeeze out nearly all the water. With a very light touch, he'd run the sponge over a small area, flip the sponge over then wipe once more. In that manner, he'd gently loosen the paint killing grit. Surface would then be ready for polish or whatever.
I use the same technique. Can do the entire car in 10 minutes. Trick is to do only small areas at a time and keep rinsing the sponge and keep the water clean.
Sometimes you have to drag out the hose, soap & water when the car's really dirty, but with a great coat of wax dirt doesn't happen often with my car. Using Quick Detailer or something like it afterwards would be a great finishing touch between waxes.

I just bought and drove my 73 rs clone 3,500 miles . Picked it up in canada drove through torrents of rain in washington and oregon and california down to rensport . What great fun ! perfect car for the trip. 911 wipers are fantastic !. Made it to socal and no more rain, untill i got back to NM .
It lives in the garage while not being driven . Next trip is the Baja California another 3,500 mile trip!
these cars are made to be driven .
just havin fun

^

This is so true.. We disassembled a 15 year old 40 mile 996 that had been stored extremely well. The amount of crap in the doors was staggering.

Minimizing water ingress in these cars gets increasingly important on a daily basis going forward. "Never driven in the rain" is a good place to start. Rinseless wash is another good idea...

The Difference Between A Rinseless Wash and Waterless Wash

I'm of the same opinion of @Mstier. If it rains while I'm out, so be it. If rain is forecast / likely, I drive something else.

The most important thing to remember however is that... Somewhere, the zebra is dancing.

Anyone who tells you their (air cooled) car has never been driven in the rain is full of crap. It's virtually impossible to own a car that long and not drive it in the rain, unless it's been in a museum for 40 years.

I love driving our totally restored ‘82 Targa, in ANY kind of weather, mostly. I use it as a DD out here and it’s fantastic. Next week it gets its winter tires and wheels put on and it’ll be a pretty good winter car. It actually has lived outside for the last year due to a remodel. It’ll go back in the garage in about 6 weeks. I’m with a number of previous posters, these are meant to be driven. I get people telling me a lot they can’t believe I’m driving a car like “that” in the weather. Oh well...

I was watching an episode of Jay Leno's Garage a few days ago and he mentioned that he didn't wash his cars. I don't remember which one it was but it surprised me enough that it registered in my feeble brain.

C’mon people, at best we get a few decades on this planet. Drive your cars! 911s are great in the rain and snow. I look forward to putting on studded tires and sliding around in the snow.

Reminds me of the kids that would keep their toys in the plastic so they don’t get messed up.

Everybody needs to make themselves happy. There is no one size fits all answer.

I was not displeased when the previous owner of one of my cars told me he had never driven it in the rain. I have dealt with plenty of rust in my time.

In a perfect world I would have my car stripped and dipped in zinc. Then I would not have to worry about rust.

A friend of mine has a poster in his machine shop that reads "I can hear my 911 rusting".

You guys with the galvanized bodies don't know how good you have it.

No or light pressure should be applied to swipe the dirt and road grime off. Most of the time, I find that just using the weight of the microfiber cloth is enough.

For grit stuck on the paint, have you tried using a clay bar ?

Washing with water is easily controlled, and fresh water. And dried well afterwards.

It's not the actual rain that is the issue, it's the dirty muck flung up off the roads into the under carriage and around the seals, and in through the engine fan and blown around everywhere. If it's winter rain and somewhere where roads ar salted, it's ally dirty muck.

Some people like their cars clean and corrosion free. Others like getting them filthy and using them in any weather. Let people enjoy their cars the way they want.

Did you ever notice where the water goes as is runs off the gutter by the windshield.
It runs down and inside the rockers!

my old SC before tearing it apart for a racecar build I would never drive it in the rain. it was not a daily driver so I could pick and choose when I drove it. a couple buddies, one specifically with a targa DD would constantly give me crap about it. I told him it was like a bar of soap and would melt. anyone here old enough to remember the woody allen movie where he escapes prison with a gun widdled from soap and colored with shoe polish? woody's luck ran out as soon as he got outside the prison where it was raining and he was left only with a handful of lather??? silly woody!


I have a non-galvanized 75 and perhaps the other most rust prone vehicle in a 90 jeep wrangler in my stable. both are relatively rust free and im not worried about rust much. im 2/3 of the way through my life in my early 50's so they will outlast me even if the rust started today. let them rust as I will keep both till my dying day...

Bought a Phoenix/San Diego '83 911.....it only lived in those two places....you could remove every bolt/nut normally to include the exhaust system and nothing had rust on it....I suspect it has seen some rain but getting a 'dry' car can save you thousands of dollars and mechanical headaches....

I never drive my 911 when rain is in the forecast, I have other options so why do it?
However, last month, I was contacted to rent my 911 for a scene in "Titans" (my car belongs to Dick Grayson aka Robin). When it first started raining, I wasn't even sure the wipers worked and if the rubber on them was soft. I ended up on the way to the set on the highway in a driving thunderstorm driving at 45 mph and seriously rethinking my decision. The high paycheck kept me going and it all worked out.

I have a 2008 PTS 997.1 Cab that has never seen rain. 10,637 mi since new.

PPI, if I ever sell will confirm stickers on underbody parts still on car and clean.

Car undercarriage looks like as delivered.

Just read the article in the link above. Sorry, but Optimum No-Rinse is a joke. ONR's recommended dilution ratio for a rinseless wash is 2 oz. per 2 gallons of water or 256 to 1. I have use it and tried hard to like it (after meguiars D114 was discontinued) but no-go. Forget their polymer technology. At that ratio, its basically water. Mix it stronger and you'll get streaks that require heavier wiping and buffing.