If you have alloy heads you're supposed to bump C/R up a point to compensate for greater heat dissipation of alloy vs iron heads....
Make sure you have a good mechanical water temp gauge and go by that. The ambient heat transfer you have just discovered is perfectly normal, so get some sleep.
I think you’re overthinking this. You drive it, it gets hot. The cooling system is working, or you’d be boiling over. At some point, everything is as hot as it will ever get, that’s how engines and cooling systems work. After you drive it, it takes a while to cool down. It can’t get any hotter, you’ve removed the source of heat by shutting down the engine. How long it takes to cool to room temperature is a matter of mass and airflow. Airflow in a closed garage is basically zero. Sympathy on the anxiety / OCD thing you have going there. Really, though, you’re just overthinking it. Let it go.
Both my 502 bbf and Boss 429 engine still have a bit of heat in the them after 8-10 hours. I can practically heat the 500 sq. ft. garage with the Boss engine after a good run. The big heavy cast aluminum rocker covers really throw off a lot of heat. A temp gun says 190-210 on the heads, rocker covers, which is normal.
The rate of reduction is duly proportional to the area of contact. A sheet of tinfoil weighing 500 lbs has a lot of surface area and will cool from 200° to ambient in a matter of seconds. A nearly solid chunk of iron, steel, aluminum and liquid has much less surface area to transfer the heat to the surrounding air. Finned rocker covers and oil pan will help it cool down faster.
I did a little experiment checking the engine heat this morning after reading this thread, I have a sbf in the '54 Ranch Wagon and when I got home from a couple of errands, I pulled the car into the shop and opened the hood trying to mimic your hoodless car, I last checked the engine by feeling the valve covers after almost 4 hours, the valve covers were still hot. I honestly believe if the engine is not running hot and losing water you really don't have a problem. HRP
Kind of like that French physics teacher did back in the 1700’s. Suddenly men began floating in air for some reason.
I would have done it last night, but the car had only been sitting for two hours, and I was ready for bed and didn't want to go out to the shop again.
Nice move, Danny. Esp. with the SBF, similarities in order; BUT! Spike's is a HOT rod, and Mrs. Primer's is a station wagon! #Spike... Please check heat with the gun when it comes, and share the outcome?
Now that you have had someone else confirm that it's not a problem, how about posting temps of the various components after a normal drive, and an hour or two later. Front brakes, bearings (hub), spring, radiator top and bottom, engine top and bottom, exhaust, torque convertor or clutch housing, trans, u-joints, diff center, each axle end (bearing), brakes, spring. Since you are concerned about this, it should do a few things: Help satisfy yourself what is normal, Help others that have the same concerns, Give yourself and others a baseline to compare and be able to spot issues.
My father always told me that if you smoke after sex, you're doing it too fast. As for warm valve covers...let em cool before you polish them.
Cast parts absorb heat, they are basically a heat sink. Cast pieces do not cool as fast as sheet metal and the heavier casting take longer than lighter castings. There was a company selling stamped aluminum rocker covers in the '90s. They absorbed heat well because they were aluminum and they cooled off really fast. Wish I had a set today.
It's nothing abnormal. If you drive a vehicle, any vehicle, for a good amount of time everything will be good and heat soaked. Coolant temps are ~190°F and oil temps will be ~230°F. These will vary depending on how the oiling and cooling system is setup. So about ~200°F Ambient underhood temps will be ~100°F hotter than ambient. Since you have no hood this will be less, but the heat output will still be there. Typical uncoated headers will add to this heat output, there's only ~.065" between atmo and ~1400°F exhaust fumes. Stop the car, turn the engine off three things happen. There is no longer the cooling of air passing over/through the car when moving. There is no longer the fan pulling air through the radiator or over the engine. Coolant is no longer circulating via the waterpump. All active cooling has ceased, now the components are simply going to radiate heat. With the valve covers location on an SBF, heat will rise, valve covers were internally splashed with hot oil, plus heat from the combustion process via the heads, and heat rising from the headers will waft over the valve covers. Aluminum is a great heat sink. Valve covers are gonna be hot, and they will be hot for a while. This is normal.
Has everyone overlooked the obvious. (thank you Capt. Obvious!) The oil gets hotter than the water......therefore & whatnot...the VCs , that are constantly in contact with super-duper hot oil would naturally get hotter than the water. And hold heat longer I would suggest. There problem solved!!! Cut'em some slack.......he's a Ford man! 6sally6
Actually....the oil cools off relatively quickly, you can tell if you pay attention to oil pressure and coolant temp. It takes a while for oil to come up to temperature, and oil pressure to drop, after you let the engine sit for an hour, even though coolant temp is still kind of high. The reason is that the oil sits down in the oil pan, with a thin layer of steel between it and ambient air. The heat radiates off the pan relatively quickly, and heat transfers through the oil relatively quickly.
Be careful not to take a breather off one of the offending valve covers. Not very often, but there could be a dangerous fire in there. It's best to wait 'til morning before safely restarting the engine. Maybe two days just to be safe. Best to park outside so not to endanger your home and garage.
The Jalopy Journal
