Are air cooled engines reliable for CA hot weather?

21.5 million air cooled VW Beetles (alone) were produced from 1938-2003 so they are already in really hot places.  A well-balanced precision built air-cooled engine built with quality parts will give long dependable service.  That said it is a 50+ year old design - the more horsepower demanded, the less reliable it could become. 

The issue is - OEM quality parts are becoming harder to find.  It used to be MX and Brazilian parts were looked down in quality over NOS German parts.  Now they are the high end compared to China/Taiwan parts.   The VW Type4 (think Porsche 914/VW 412) is also a more modern ('70-76) air-cooled base engine (stock 76-106 hp but can easily make 150+).

Subaru gives you a modern VVT/FI boxer engine with great horsepower (170 up) for not much $ - so it is a natural replacement.  You'll also find Speedsters with 1.8/2.0L Audi/VW water cooled engines up to 911 3.7L engines - there are even ones with 996 Boxster (Starke) underpinnings as well as Mazda Miata. 

Define “reliable”.

Here are some photos of the engine the seller sent me.WOLFGANG posted:

21.5 million air cooled VW Beetles (alone) were produced from 1938-2003 so they are already in really hot places.  A well-balanced precision built air-cooled engine built with quality parts will give long dependable service.  That said it is a 50+ year old design - the more horsepower demanded, the less reliable it could become. 

The issue is - OEM quality parts are becoming harder to find.  It used to be MX and Brazilian parts were looked down in quality over NOS German parts.  Now they are the high end compared to China/Taiwan parts.   The VW Type4 (think Porsche 914/VW 412) is also a more modern ('70-76) air-cooled base engine (stock 76-106 hp but can easily make 150+).

Subaru gives you a modern VVT/FI boxer engine with great horsepower (170 up) for not much $ - so it is a natural replacement.  You'll also find Speedsters with 1.8/2.0L Audi/VW water cooled engines up to 911 3.7L engines - there are even ones with 996 Boxster (Starke) underpinnings as well as Mazda Miata. 

Thank you @WOLFGANG for the reply! I’m looking at one car, it’s vintage built but he says the old owner had the engine changed to this....”The big bore dual port, features CB performance fuel Injection, MSD ignition, 042 high performance heads, headers with dual outlets and much much more. This engine has a 6000 rpm chip in the MSD 6al CD box”. Does this sound any good? I don’t understand much about it, hence why I’m looking for help from people like you!! Thank you again!

Stan Galat posted:

Define “reliable”.

@Stan Galat would it be able to handle long drives in hot CA weather conditions since it’s air cooled? 

Mike,

The fact an engine is air-cooled should not prohibit its use when the air temp is high, or on long trips.  In general, there are thousands of air cooled engines in replicas, doing exactly what you describe, i.e., operating in hot air temp on long drives.  The difficulty is to apply that general principle to your specific engine.  If your engine was built well with quality parts and maintained properly, you should have few problems.

It is also possible to decrease oil temp by installing an oil cooler, if you don't already have one.  If you have concerns about your engine status, you may want to have a pre-purchase inspection done by a qualified mechanic/shop.  

Air being a less efficient cooling medium than water, the engine is more sensitive to ambient air temperature changes. The hotter the air is that the fan is ingesting, the less efficient it is at carrying away heat, so the engineering of the engine install becomes more important. One of the factors concerning engine cooling is air intake temps. I would bet that if you took a Speedster that just seems to 'run cooler' you'd find that the temp inside the engine compartment (measured with a remote thermometer) is at or near ambient most of the time while a Speedster with a similar engine that 'runs hot' has noticeably higher engine compartment temps. As I said, the install is important- with different manufacturers and a lot of Speedsters being home built, none of these cars are exactly the same and everything that will work for one car is necessarily beneficial in another.

That said- there are a lot of members here running around the southern States, and a fair number of them drive their cars a lot. Unless a car has an obvious overheating problem, I see no reason that an aircooled Speedster can't do what you're proposing. You may have to watch the temp gauge in hotter weather and dial the speed (and rpm's) back a bit if the car starts getting into the upper reaches so it doesn't get too hot. I wouldn't try to set any speed records across the desert during the middle of summer, but you should be able to enjoy your car in all but the hottest weather.

THAT SAID, if you're truly looking for a something more foolproof, (and boy, how I hate to say this) Subie power is a viable alternative.

Hope this helps. Al

The aircooled engines leave less room for error in the build and setup to run with reliability and longevity.  The engine you described if built by CB performance with fuel injection should be a well built engine. if installed correctly should be no problem in hot climates. As others have said the aircooled engines do need watching and tended too to survive. They are not usually suited to jump in and drive owners that don't have mechanical abilities and a sense of how the engine is designed to function, IMHO of course. I went with the water cooled Subaru power because I wanted reliable no hassle power without the worry of when something was going to break.

@Mike_z85

Mike, in SoCal you should have no problem with an air-cooled Speedster. The reply that @Jim Kelly posted is to the point, a "properly built and maintained" Speedster will provide you many miles of enjoyment in SoCal. Even the drive from your location to Palm Springs area would be no problem.

There are many SOCers in SoCal driving their Speedsters where heat or distance has not been an issue. Mine is a daily driver (Orange County) and have been to the high desert (Palm Springs, Palm Desert, Indio) many times without issue.

Best of luck in your Speedster endeavor! 

A downside to the T1 VW engine is the requirement for frequent oil changes and valve adjustments (as well as perhaps timing unless converted to pointless).  A stock VW engine only holds 2.5 quarts of oil.  Most still use dino oil with zinc additive so you're looking at oil changes every 3k miles.  OEM T1's didn't have an oil filter - just a screen to filter the really big chunks.  The more modern T4 engine held more oil and actually had a spin on oil filter. 

So VW air-cooled maintenance is higher - but simple for the owner to do as part of the hobby.  Cute book available - Idiots guide to keeping a VW air cooled engine alive.  Most modern engines go 7500-10000 miles to full synthetic oil changes and never get a valve adjustment.

An engine with FI and MSD was probably put together by a knowledgeable VW guy.  We used to kid here about the stock mass builders use of Mexicrate engines - built with cheapest parts available (don't ever mention GEX engines).

Oil cooler and larger oil sump combined with a well built engine and you should have no issues. It was not mentioned that the other advantage of a Type 4 engine is hydraulic valves that do not require adjustment. I know they are out there but I have never seen one at any of the events I have attended. The Subies make more HP and are reliable and have plenty of HP for A/C. However the sound is just not the same for us old farts. 

I have a hot running engine in Penny but you can do things to keep them cooler, several have already been mentioned. Fuel injection is a plus if it was done properly although I don't know of many that really work like modern FI. 

Subaru powered is definitely the way to go if you're looking for more reliability and less maintenance. But retrofitting Subie power can be costly unless you can do it yourself.

My advice for a newbie is to find and buy a good used car with a good history and see if you really like it. They aren't for everyone. The cool thing in this current market is that you can almost get what you paid for it. You might stay with your used Speedster or you might upgrade to a new one built to your personal specifications.

Stick around here, use the search function to become more familiar with the cars and ask a lot of questions. Reach out to members in your area for a possible test drive.

Welcome aboard.

Mike_z85 posted:

Stan Galat posted:

Define “reliable”.

@Stan Galat would it be able to handle long drives in hot CA weather conditions since it’s air cooled? 

Short answer: Absolutely.

The longer/ more complete/ better answer is pretty nuanced, and gets into a series of questions that defy quick and easy answers. Yes, there were 25,000,000 made, but the Type 1 was designed in the 1930s to be cheap and easily replaced. They have proven to be amazingly flexible and versatile engines that can be cheap, reliable, and amazingly powerful— but not all 3 things at the same time.

If you require all 3, I’d kindly direct you to the local Ford or Chevrolet dealership. There’s a man standing in the shade right now, ready to put you in the seat of a new Mustang GT or Camaro SS— or you could buy a ‘vette and prove once and for all that you know how to sink 3 for 3 better than any of us chumps. We’re a bunch of misfits who hate spare time and money.

I did a 3- year tour with a mission in the Southern Highlands of Papua New Guinea back in the ‘80s. We ran a VW Type 1 on a portable sawmill to produce lumber for local development projects. I’m pretty sure that engine would’ve run on waste oil and mineral spirits. We used to carry it up and down mountainsides to set up for a new cut, sometimes upside down. We worked on it with sticks and baling wire. That engine was super-cheap and dead-nuts reliable. It also made slightly less power than a 2-cyl Kohler lawnmower engine, so we hit two out of three (which ain’t too shabby, and was the bullseye we were aiming at).

Later in life, I took a Type 1 Speedster from Illinois to the left coast across Utah, Nevada, and the Mojave desert. On purpose. For fun. Twice. The first engine (200 hp) was crazy powerful, and certainly not cheap. Unfortunately, I didn’t get much in the way of reliability either (I split a cylinder, and threw enough oil to be a one man mobile Superfund site). I was hoping for two out of three— but alas, it was not to be. The second (130-ish hp) didn’t break (too badly) and didn’t cost $10,000, so it was a bit better. I’d call it .500.

I would not hesitate to take my present engine on the same trip (if it weren’t on jackstands at the present moment because it attempted suicide by immolation last fall in North Carolina, out of spite, one supposes). But I’d definitely have my “travel kit” full of spare tools and parts. And a credit card. Perhaps two. And a cell phone. Other than that, it’s perfectly reliable.

I’ve also played with cars and mechanical things my entire life, so there’s that.

I’m in no way trying to run you off, but I think a bit of tough-love on the front-end serves everybody better in the long run. It’s always a good thing to know where you’re getting into. If you expect this to be a “jump in it and drive” Toyota Camry kind of deal, without paying attention to the engine (how it smells, how it’s running, what the gauges are telling you) then you will be one of the many people who “reluctantly” sell after 500 miles. This includes cars with Subarus, BTW (they are a much more modern design, but they are in the hand-built car).

Mechanically, an air-cooled engine shares more traits with outdoor power equipment than with a modern car. If the spring start-up of your lawnmower frustrates you, you may want to think twice.

If you have no mechanical experience or aptitude, the next-best thing for you is to understand that you will need to establish a very close friendship with someone who does.

These cars are worth all the compromises— but if you think you are going to make any going into this, you will be very disappointed very quickly.

Forewarned is forearmed.

Thank you all for all the great responses! I will keep y’all in the loop as soon as I go test drive a few cars this weekend! 

@Mike_z85  i had a 1965 squareback (my 1st car) and a 69 van growing up...and became a semi-expert on VW's...and not because i wanted to....which is why i got SUBIE -POWERED replica...in my retirement age, i'd rather drive than wrench...and i'll leave it at that....like the knight in the indiana jones movie said  "be sure to CHOOSE WISELY"

...or you can limit your driving to late evening or early morning morning cruises which is what I did in Atlanta. HOWEVER, my car has been in Indiana awaiting a Suby transplant since November and I should be getting it back any week now...

Meade posted:

...or you can limit your driving to late evening or early morning morning cruises which is what I did in Atlanta. HOWEVER, my car has been in Indiana awaiting a Suby transplant since November and I should be getting it back any week now...

Please start a new thread and post lots of pics and info on your transplant after you take delivery, Meade. This is a somewhat hot topic these days and it would be beneficial to many to hear about and see pics of the conversion. 

  You can search the thread named " My Fiberfab suby conversion " for the thread on Special Edition converting my speedster last year.

Mike, you'd think a simple question like yours would have a simple answer.

But you can see from the number of responses - and from the length of some of them - that this isn't at all simple.

As Stan says, if you mean jump-in-and-drive Toyota-like reliable, the answer is probably 'no'. Carefully built, properly set up, and driven like you had to drive any car in the 1950s, yeah, they can can get you where you want to go with no problems.

But remember, you're talking to the lunatic fringe here who are so taken by these cars that we're willing to learn the necessary rituals and make the necessary sacrifices to drive them.

By modern standards, they are hugely impractical, very uncomfortable, and cantankerous to maintain. Despite all that, and maybe because of it, they can also be more fun to drive than any modern car.

Yeah, VW made a bazillion air-cooled cars which were mainly considered reliable in all climates. But almost all of those had engines of 50 hp or less. If you want to keep up with modern traffic (especially on freeways or interstates) you'll probably want more like 100 hp (or more), and modding one of these engines to make that power and stuffing it into a Speedster-sized engine compartment, means that serious thought needs to go into designing in proper cooling.

It can be done, but you need to make sure it WAS done on the individual car you're considering.

You didn't mention bore and stroke or displacement. Larger displacement engines tend to run hotter, all other things being equal. The original VW engine was at most 1600cc, yet there are plenty of people running displacements over 2000cc, a lot of them in hot climates. The key is cooling.

A lot of people talk about oil temperature, which is important in an air cooled engine because the oil serves to col as well as lubricate. A full-flow filter kit with external oil cooler are essential with a large-displacement engine. Another issue is oil viscosity. In hot climates, run 20W-50 so the oil doesn't get too thin and bypass the oil pump gears, causing low oil pressure. I like to see a minimum of 10 PSI at idle and 30 PSI or better at highway speeds, when the engine is operating at temperature.

Perhaps even more important is proper cooling and air flow. You don't want the cylinder heads to overheat, as it can damage the valve guides. Ensure the fan shroud and all of the engine tins are in place and any holes between the tins and the body are sealed to minimize recycling of hot air back to the fan intake. Especially important are the tins under the cylinders which direct airflow to the rear. If you can look straight up and see push rod tubes, these tins are missing. This is common on dune buggies, but bad news on a Speedster, or any vehicle which will sit in traffic. You want the hot air directed out the rear of the vehicle, not gathering underneath where it can short cycle back into the fan. If the engine doesn't have heat boxes, make sure the "industrial" tins are installed.