Is it true that 308's delivered in Europe did not have AC and it was a feature of North American cars? If so ....did Ferrari use the same radiator in both?
A car with AC would seem to need a larger radiator with a condenser in front of it putting out heat. If the system was designed for no AC and one was added without increasing radiator capacity, it could explain why so many 308's with AC run hot.
I believe you're approaching the design spec in reverse. The goal would be to design a single radiator that cools the engine sufficiently with the AC condenser in place. If the condenser were to be removed (or not ever installed), then airflow would of course increase - but that doesn't mean that WITH a condenser, that the original design isn't sufficient.
There are a number of factors that could cause a car to run hot but I don’t think the size of the radiator or installation of an A/C condenser are among them. Otherwise all cars would have run hot right off the showroom floor and that’s not the case.
If it’s an aftermarket condenser and it’s not design for the original radiator, it can insufficiently reduce the air flow for the radiator to cool down, by several degrees, believe me I’ve seen it happen.
This"run hot" thing is mostly a QV issue, not a 308 thing in general. What I mean is if someone's 79 308 is inching up in temp in traffic today, it probably just needs rodding out, etc. A QV will still tend to do it even with a bigger radiator depending on where you live and what time of year it is.
The thing I don't understand is that most 308s cool just fine when they are moving at speed yet some of these same cars cannot idle in traffic for more than 20 minutes without getting hot. The difference in the two scenarios is the amount of airflow. The thing I don't understand is why bigger better radiators are the solution rather than bigger and better fans.
I have an aftermarket radiator, which may be better than a very old crappy radiator, but wasn't cooling my car sufficiently. Upgrading the fans (plus that radiator I guess) has made everything much more acceptable. I know there are very strong opinions about whether or not original OEM fans are sufficient, but I believe they aren't in many cases (end of life, so to speak)... or at the very least, I believe that modern fans can absolutely improve cooling performance.
A bigger radiator isn't going to fix it. I have one of those big ass aluminum ones. Put it in about 4 years ago. It's weird how it affects the cooling. Running down the highway the needle will barely get a quarter to the right now. It is a noticeable difference from before (actually a very big difference) but I never had a problem on the highway in my life before. It could be over 100 outside and as long as I was moving at 60 + the needle pointed straight down. Even on the track in Aug it never ran hot. Oil temps would peg but the water was spot on normal no matter how long I stayed out bouncing it off the redline. But stop and go traffic inching through downtown Atlanta it STILL gets too hot. The radiator only cools the hell out of it where I don't need it.
The factory fans on a QV suck and that is irrefutable. No one loves Ferrari or a Ferrari 308 more than me but it is what it is. They under engineered the cooling system design and that is just the bottom line. Wedge a couple puller fans with greater efficiency behind the radiator and that problem should never see the light of day again. I have a temp spare and I keep telling myself that one day I will get a junk spare tire well, cut the front out of it, re-fiberglass it, paint it black and use it with the temp spare tilted up and back. This will provide space for two pullers. In the mean time I'll just keep doing what I have been doing for 22 years and that's just plan trips around rush hour.
I don't believe there is much performance difference between pusher or puller fans. There is lots of room in front of the radiator for pusher type, so personally, if I were to change fans, I would use pushers I would expect that the factory fans are completely obsolete. New modern fans with modern design blades and modern design motors would blow a lot more air and may solve the cooling while idling problem. I have heard very positive recommendations regarding modern Spal fans. It looks like two 12" pusher fans would fit quite nicely in the front of a 308. The Spal 30102030 is a 12" curved blade pusher rated at 1,300 cfm. Although Spal offers both pusher and puller configurations, they list performance characteristics for all fans on their pdf spec sheets in both configurations. The performance difference between using a fan in push or pull configuration is small. The problem is that Spal 30102030 fans would draw 14 amps each. I would like to know the current draw of our factory fans. Likewise, it would be interesting to know what the rated airflow rate is for the factory fans.
Not completely sure about this, but I think I recall some mention of early 308 literature quoting a weight without AC (they wouldn't want to create any uncertainty to the light side about how much a 308 weighs would they? ) -- whether, or not, they built any/many without AC, have no idea.
Dr Tommy, I really don’t think the original QV radiator fans sucks at all. I’m sure I’m not the only one here that can say I still have the original radiator and fans and never had any overheating problem in 12 years of ownership, even when I get stuck in a 90+ degree temp in an Los Angeles bumper to bumper rush hour traffic during summer. Where the QV having problem overheating when they came out of the factory or dealership? In fact, I too have the Nick Forza Aluminum radiator that was design for their 4.0 ltr block that I never use as there’s no need for it. If a car is having problem keeping the cooling system cool, then there’s definitely something is no t working right.
You live in a comfortable environment. I think that is part of the variable with these cars and the cooling systems.
My 76 has no AC from day one...it's a U.K. Car and after I asked around there are several others as well. Also some folks who have had their cars since new, said they had to ask for it and pay to get AC, in the U.K.
Two thoughts: 1. I think terms such as "keeps system cool" are sort of vague, and may sort of obfuscate discussion. IE - what's "cool"? (I'm not directing this at you, Mike - your post was just convenient as a launch). So perhaps better to discuss an actual temp. In my own car, I consider just below 90C to be an acceptable "summer" temp (I live in Northern Florida. Humid & Hot.) In bumper-to-bumper, it can rise to the 105 range with the fans blowing hard. If I turn the AC on, it's absolutely going over 90C in traffic. 2. The only time I've ever had the car literally run too hot was due to a old/bad tank cap, which then led to a subsequent hose failure after the boilover. (I believe the boilover created such pressure than other hoses/clamps were compromised) I've upgraded the fans, yes - and temps in summer driving have benefited. But at the center of it, was getting all the mechanical issues (hoses, cap) addressed and then adding new fans as a bonus. The better fans have helped, but nothing helps a car with an inherent other issue.
I had my car for about a year and it never overheated, all through the summer even in city traffic. I put 10,000 miles on it. But eventually it began to get hot in such situations. I replaced the pressure cap, the thermostat, the radiator, the waterpump and the fans but nothing stopped it and it was getting worse. Eventually I found out I had a blown head gasket. Going through all of this I learned a lot about the 308 cooling system and one of the things was that when you are filling a drained system and you haven’t put pretty close to five gallons of coolant in you ain’t done yet and until you have that whole five gallons back in there (actually 4 3/4 gal or 18 liters to be exact) it will do various weird things such as appearing to run cold and displaying rapid swings of the needle and trapping air in the top of the radiator. There is a ton of stuff written about this and I’ve read it all. The threads lead down all sorts of paths some resolved some said to be resolved and some abandoned but my conclusion is that if your car is overheating something’s wrong. It’s not a “feature”, not even for the QV’s, they didn’t do it when they were new.
A common mod is to replace the fan switch to a lower temp one too. I had my radiator re-cored. The local old-school guy I went to said copper cools better than aluminum and he was able to find a core to replace mine with as it had started to develop tiny little leaks in the tubing. You'd never know it had replaced if you didn't actually look at and count the number of rows. I also put newer fans on but I'd have to look it up to see which ones I used. They fit just fine and obviously pushed a lot more air than the old factory Spal units.
Going to agree with Mike on this. My 82 would run hot when I purchased her. Lots of factors play into the problem. But the efficiency of the factory Lucas fan setup that is working properly is not the issue. With that said, the Lucas fan motors' brushes do wear out with age, the shaft gets play and wobbles, they draw more current, they overheat the fuse box and help to ruin those, and ultimately the fans don't get to full speed. The fan motors are a wear item that should be replaced. Same with the old fuse boxes. Replace those motors new, insure your fuse box is up to snuff, and any fan related issue goes away. The other things you'll see on these cars are missing foam to force air through the radiator resulting in air leaking over the top or sides of the radiator, clogged radiator cores, failing water pump impellers and thermostats, failing expansion tank caps, leaking expansion tanks from corrosion, scale build up from improper coolants, and improperly bled coolant systems.
I have done all those things over the past 70,000 miles. Some many times over. Car never overheats or even runs hot, ever - except in stop and go traffic.
