308 QV Radiator

I ordered a new radiator from Wizard earlier this year. They have two models for the 308. The thicker model requires you to remove the fiberglass spare tire holder. I ordered the thicker unit and wizard called me to explain the difference. So I chose the direct replacement that didn’t require removal of the spare wheel tub. I fully shrouded the new radiator and added 2 ten inch spall fans.

 

You will need to disconnect the AC. I'm not sure there is anyway around it.

 

Here is a picture prior to building the shroud. I did find the upper brackets were slightly miss-measured and required some work to fit properly. These units are all handmade so there may be some variations.

 

My '83 QV had not liked idling when the temperature is high (i.e. above 90F). When I had my the radiator disassembled and cleaned, the shop (San Jose Radiator) said that it was 50% plugged. I was surprised.

The shop said that fin density is an indicator of radiator efficiency. They also said that stock 308 radiators have the highest density (14 fins per inch?) than any other car they service. They are good radiators.

 

I agree. I only replaced mine when it started leaking...and I wanted to upgrade the AC condenser. My temp gauge would read up to and over 90C -110C, but the EFI never indicated more than a few degree change. Don't trust the gauge! Also, the factory gauge doesn't compensate for voltage changes which affects accuracy.

 

Another thing too about our gauges is that they are not "tempered" like modern gauges.

The needle of a tempered gauge quickly moves to the center and stays there until the engine is about to overheat at which time the needle rapidly moves to the right.

Our gauges move accurately according to temperature and the engine is actually only overheating when the gauge is almost pegged to the right side of the gauge. The needle can move considerably to the right before there actually is a problem. It can look pretty freaky.

 

In my case, and the reason I bought a new radiator, was that I had a blown head gasket. When I first got the car it worked fine. At idle, with no motion, it would rise to 195, the fans would turn on, it would drop and the fans would turn off. Eventually though the temperature would continue to rise and the fans would not turn off. It would still act normal when in motion where the temperature would never reach the 195 mark but eventually it worsened so I tried new cap, new thermostat, new water pump and then a new radiator. During all of this work and troubleshooting I finally discovered the head gasket issue while doing a leak down compression test, it was leaking into the coolant on #4 cylinder. FWIW I did several "block tests" where you sample the air at the top of the coolant tank for combustion gasses but it always showed negative so in my opinion that is not an accurate test, at least not for systems with expansion tanks. The combustion gases were most likely trapped at the top of the radiator so the test never "saw" them.

So bottom line is that I agree the system works but over time the connections and bearings/bushings for the fans can degrade their performance and cause them to be less effective due to voltage drop or drag resistance. Also, as in BrianA's case, the radiator can get a bit scaled up after 35-40 years. Also, as noted, people tend to freak out prematurely because a 50/50 glycol solution at 1.1 bar doesn't boil until it gets to around 260F. But I can tell you that if you do have a problem like I did the engine will overheat and nothing short of replacing the blown head gasket is going to correct that.

 

My experience (328) from last year (from the TR/BB forum):

My experience is with recent "correct' re-coring of a 328 radiator (not a Boxer) but of similar vintage. I believe you are correct, the radiator shown has a serpentine fin core and per my understanding (at least on the 328) the "correct" type was a continuous horizonal fin. I too had a small leak (only when hot) and elected to replace the core rather than fix one area only to eventually contend with another site on a 35-year old original core.

Mr. Yang referred me to Mr. Rick Piper at Port Chester Radiator (https://www.portchesterautoradiator.com/contact-us/1924941) - I simply cannot say enough good things about both Mr. Piper and the experience. As I too wanted a "concourse-correct" repair he had Maine radiator supply (https://maineradiator.com/catalogs/) duplicate the original radiator core in appearance and dimensions (including the 328 center divider) and reused the original upper/lower tanks, all for a very reasonable cost. Communication was superb, craftsmanship excellent, and he is very used to working on Ferrari radiators and shipping as needed.

Hope this is helpful.

 

https://www.urotuning.com/products/neuspeed-fan-switch-2-pole-fox-jetta-rabbit-gti-rabbit-scirocco?variant=41306462355649
They are still available

 

The only thing a 180 switch does is keep the engine from reaching operating temp sooner.

Imagine you want to make some pasta. You can fill the pot with tap water, or you can fill the pot with ice. Either way, it's eventually going to boil... except one will simply take longer than the other.

 

What I've observed is that driving down the highway, my car is fine... actually, I worry it isn't getting up to temp sometimes. In slow traffic or standing still, in warm weather, it will run up to 195F, the fans kick on, and it cools down a bit. I'd rather it cool down a bit sooner than that... no reason to live on the edge. I've got a 180F on the shelf and will be installing it, curious to see what effect it has.

 

Everyone reading this: a 180 degree fan switch may or may not address a "problem" but they are cheap and will cause absolutely no harm to the car.

At all. I have proven that beyond any shadow of a doubt.

 

You're sitting in your house. It's 110F outside, and 95F in the living room. You turn on the AC to 80F, AC kicks on. The house will not reach 80F faster, if you set the AC on 40F. If your AC is capable of keeping your interior at 40F, it will do that... but now you're maintaining an uncomfortable living temp inside the house (or your put on a sweater). But in either case, the rate at which the temp dropped from 95F->80F was not effected by the AC being set on 80F vs 40F.

That's sort of apple vs orange, as certainly you could set the AC on 78F, and be assured that it will probably maintain 78-80F (your desired temp.) But that analogy doesn't really apply, as we don't run the car 24/7.

But thermodynamics aside, there are additional factors to this. The thermostat at the water pump doesn't care if the fans are turning or not. Obviously the coolant temp (affected by fans) is the factor, but ultimately we *want* the engine to to hot enough, early. If keeping the engine at 180F was the ultimate goal (assuming a perfectly efficient radiator/fan), then the engine thermostat would open at 180F, not 195F. Cold engines mean cold oil, cold lubrication passages, and poorer lubrication on bearings, piston rings that aren't fully expanding, etc... that's why we don't redline the engine just after we crank the car.

Yes, the cooling system in the 308 has some design flaws, but it's not just a matter of a fan not kicking on sooner. The reason for a car that is overheating is due to leaking hoses & radiators, old tank caps, plugged radiators, dying fans, or faulty thermostats.

 

You left out "under-engineered from the factory on a car in Florida in the summer"

 

I do live in Florida...

 

Ok, so you just left out the under-engineered QV part.

 

My first day in the 308 was when I picked it up in Birmingham, AL and drove home to Florida. It was a hot sunny day in July when I started the trip home.

30 Mins in the car, and it began to rain. Pulled over at an exit, put the top back on. Rolled up the windows, and turned on the most useless wipers ever installed on a car. 20 mins later, there was a wreck on I65 before I got to Montgomery. For about a hour or two (felt like a week) I was driving somewhere between 0-5 MPH.

Car never overheated....the driver, definitely. AC wasn't working at all... windows rolled up for 4 hours ... took me about 7 1/2 hours to make a 5 hr trip, and that was a great first day of ownership.