351W operating temps....

[Mike Thompson]

Does anybody know the 'normal' ranges for a 351w as far as water temp and oil temp? I've got a 180 degree thermostat and my temp runs right at 95 to 105 degrees centigrade...which I think is pretty acceptable. On a trip to the Sonoma Historics last weekend my new oil temp gauge seemed to follow the throttle above 75 to 80 MPH. At about 65 MPH, the oil temp hovered at about 100 degrees centigrade, but above about 70 mph it would climb with the throttle and seemed to max out at about 130 degrees C. at 80+ MPH. It's probably within specs but I'd like to know when to shut it down and let her cool.

Cheers,
Mike

wolfpack68@rocketmail.com

[aspenbubba]

I have a 351-W in my BDR and your temps seem a little high. I only hit 100 o once when sitting in traffic during a "parade". Some of the other Cobras started overheating. I usully run about 80 or slightly above in very hot weather. My oil temp never gets above 100 either. I have auxilary fans and run them always.

[jhv48]

What radiator did you put in that FFR? The single row?

Also, what rear gears and fifth gear ratio do you have? A 3.73 and a .82 fifth gear will mean you are probably turning north of 3000 RPM at 80 MPH, so your temps will run high.

Those temps are MUCH higher than mine. But, I run a 3.46 and a .64 fifth gear.

At 80, on the freeway, my engine is running around 2300 rpm, and my temps are around 70 degrees C for the water and about 85 degrees C for the oil.

[Snakebit]

yo guys, if you have a 180 thermostat, then why are you using celcius??? I have to do fahrenheight to celcius conversions to understand your posts. I'm
too old to remember those math equations!

[jhv48]

70 c = 158 f
85 c = 185 f
95 c = 203 f
100c = 212 f
105c = 219 f
130c = 239 f

[bobcowan]

Oil is heated mostly by rpm's. The faster the engine spins, the higher the temps will be. I don't turn the cooler on until it hits about 220*F or so. In normal street driving, the water and oil tend to be pretty close to each other.

The thermostat controls the minimum water temp. What happens after that is all up to the cooling system. Assuming all is working well, of course. A by product of power production is heat. The more power you make, the more heat you generate. If you build up the engine to make a lot of power, you'de better build up the cooling system to match.

Your's sound just about right, nothing to worry about.

[Sledge]

My 351W normally runs between 88 and 95 deg C water temp with electric fan always on--except for when I'm on the freeway for more than a couple of minutes.

I put in a slightly larger all-aluminum radiator and changed to a single 16 in fan with shroud because I had observed coolant temps of 100+ deg C on a few occasions. 95 deg C is pretty much the max that I see now.

My oil temp has reached a maximum of 85 deg C during extended stop and go driving. Any airflow cools it right down to about 70 deg C. (Canton road race pan and 8 qts).

Cheers

[Mike Thompson]

Here's more info: The rear end is a 3:27 and it's a C-4 auto 3 speed. I am running about 3500 RPM at 75 to 80 so that puts me well into the meaty part of the powerband. The radiator is a Modine with twin fans. No oil cooler.

Mike

[barabar]

Just a short note. There are so many things that can cause abnormal temperatures. Most people think that small radiators, fans, high or low thermostats. Even though that maybe part of the problem the other causes, can be clearances espeically thrust bearing. The other problem can be the degree of valve overlap.If your header size is wrong and your not scavenger all your exhaust gases (providing your timing is correct) this can be a major issue.

[CSXDreamer]

Is you radiator completely shrouded? My factory built LAX neglected to do this, so some of the air that comes through the huge Cobra front opening is free to go over, under and around the radiator. Over one winter, I seald off the top, bottom and sides of the radiator so all the air coming throught the opening has to go through the radiator.I noticed an immediate difference the first time I took the car out. The radiator fan came on about 2 miles further aong the same road. I only drive for short trips in the summer, so I've never seen the fan cycle off. I've got a 180 deg. thermostat, but I'm not sure of the "on" temperature of the thermo fan switch. The "off" temperature of the switch may be below the 180 deg. F of the thermostat. With the t-stat holding 180, the fan won't be able to cycle off.