So the old guy that is going thru my pops flathead for our father son T roadster build says we don’t need to run a fan. Reason being is we have a kool old Navarro 3x2 intake without the generator/fan provision. I think this is absolutely asinine thinking. I’m building this thing to drive not sit on the side of the road puking coolant. Old guy says when He grew up in California they never ran fans. I need input, I think I’m in the right but who knows? Give me your two cents.
1/4 mile at a time.... maybe not, real world driving... you need a fan! Maybe the old fart thinks you're just going to be driving in those temperate Soud' Dakota winters!
I don't have a fan on my 59ab powered '33, but I do have an electric fan...... I think you gotta have something to keep that flatty from melting.
I have a french 255 flathead in a 34 Ford and run a fan permanently. I found out I don´t get enough heat in the engine so I removed the belt that drives only the fan. The 34 radiator is so big that those almost 20 litres just got 10 degrs hotter - still just maximum 70 degr C. I will need thermostats more than a permanent fan...
I think the old guys memory is failing. Idling at the lights you need a fan, with 3 x2s you will need an off set generator and to fabricate a central fan or close your eyes to an electric fan .
There are guys not running fans on this site but won’t admit it for obvious reasons. I don’t see a reason not to use one.
A friend has a 38 Phaeton, mild cam & 2 carbs. No fan, never had one since I've known him. Runs 180 in Ohio summer time.
My avatar had no fan, but in 1958 there were no traffic lights in our town. I do remember once on a trip to car show it overheated at a light. BTW 59L block, 304 cubic inches, Edelbrock heads, triples, 400jr and an angledrive front mounted vertex.
Ill Put a fan on it hell or high water. And it will not be electric. This ole boy knows his shit when it comes to putting a flathead together I’ll give him that but I just dont see the reasoning on not running a fan. I’m usually the penny pincher and will make parts so I don’t have to shell out money for something I can build but I’ve always bucked up and bought the best radiator I can get. I don’t want to be the guy at the local Cruze that is sitting on the sidelines because his car overheats!
I have an 8ba in my 36, I run a pusher electric fan which does cut in when stuck in traffic and we are still in a mild spring. Will be interesting to see how the car handles real hot days in the summer.
Steve didn't run a fan on his 32 for a long time, but when he finally put one on, it quit pinging so much....
Driving down the road at some speed? Any car should handle that, the speed pushes cooling air through the radiator. Crawling in modern city traffic, standing still at the red light or anything else moving slowly or not at all? Anything without a overkill cooling system will get quite hot then.
A historical perspective: I'm 79 and started playing with cars in 1955. My neighborhood mentor was a couple of years older than I was and I thought his words were golden. He told me that fans robbed horsepower and weren't needed. Some of my friends thought that as well and consequently didn't run fans. We had no problem as long as we never got caught in traffic, stopped at a long stop sign or set and idled a car. Fans are unnecessary when the car is moving, hence the flex flans that were popular in the seventies and the fan clutches used today. The bottom line is that you don't need a fan if the vehicle is moving but you do if not. I have run a fan in everything since about 1958 when I got my drivers license but I knew a lot of guys who didn't. Your old guy is right that in California in the golden age of hot rods many people did not run fans. There were big barrels of water on the sides of every long grade in California with pull outs where even the cars with fans pulled over to refill their boiled over radiators.
Place names like "Radiator Springs". Yeah they only had maybe 4 lb pressure caps, and running straight water, so very little boilover margin on a grade I betcha.
Since most agree a fan is needed, then the issue becomes, how do you put a fan on a flathead with "kool old Navarro 3x2 intake without the generator/fan provision"?
At around 60 MPH a fan is not necessary. Problem is that sometimes we have to drive through town. I have tried running engines without fans from time to time. It just does not work as well as we would hope that it would.
On my 32 (39 F-H & walker Z ) in summer (Va) stop & go traffic Fan was required , Dual carbs with Fan on generator, fall /winter I made a clear Plexiglass grill insert to stop air threw Radator would not get over 130deg ish with out , even with 180 &195 thermostats,
I have a friend who did not run a fan on his flattie when he lived on Vancouver island where the air is humid, however when he moved to the B.C. interior [Okanagan] where the air is hotter and dryer , he had to install a fan. I ran my T roadster pickup around the Okanagan and even to Spokane Washington to the swap meet for over 10 years without a fan blade, but I had a 276 Desoto hemi which holds a lot of water
I have run flatheads exclusively since 1964(sophomore in high school). When I read somewhere that a fan takes 5-7 hp from an engine that is short on h.p.,I did the unthinkable and started running all my hot rods(over 8 cars over a 50 year period) without a fan of any kind(including electric). 35 years ago, I had a full fendered 32 5 window with a hood and a Italmeccanica(pre SCOT) blower and no fan. Today,I have a 32 cabriolet hi-boy,no hood,and a $900 walker radiator and a accurate SW mechanical gauge. Car never gets above 180 even on a hot,humid 100 degree Texas day as long as the car is in motion. Even stopped at a red light or two for 3-4 minutes ,temp may get up to 200, but comes right back down quickly with only slight motion of the car. People look my car over closely at a car show and often ask where the fan is and I tell them I don’t have one. They argue “you got to have a fan” and I tell them I don’t and they walk away just shaking their head. Part of the mystique of no fan on a Flathead is getting the internals of the block super clean. I fashion an extremely sharp pointed hook that I can reach inside the big hole on each side of the block where the pump fastens to inside along the pan rail and force the point to dig into the corrosion and left over casting sand that remains in the block. There is often an inch or two of sand that is packed along the pan rail and just flushing with water and chemicals won’t get it sparkling clean. Using the long coat hanger hook,dig the pointed end into the hard packed substance to break it up and flush away. Another “trick” is to get a large piece of plywood and “tumble” with some force over and over—-surprising how much”schmegma” falls onto the plywood after numerous tumbles. A clean block is a cooler running block;I spend all day with the pointed “rake” and plywood tumble even after a cleaning from the machine shop.Then it’s a NO FAN situation from then on!!!!
I run with a fan but was removing it at the drag strip over the summer. The temp would creep up when stopped but all in all wasnt an issue when the car was in tune. But I feel like you really should have one. If it were me even though a 3x2 is cool id skip it and run a 2x2. At least around here intakes are not too difficult to pickup used. Ive run both offys and edelbrock where the generator and fan are in the stock location. Straight forward. Theres no street flathead that cant be feed with 2 97s.
I have a 31 A with a bbc and it had an electric fan and if I turned it off on the freeway my temp would climb because it inhibits the flow on my rad, so I turfed it for a regular fan. I think what flatheadjohn47 says is worthy of consideration.
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