Overcooled oil on dry sump?
Discussion
Anyone here run an inline thermostat on their 7 with a dry sump. I have a 420R on which I have added an oil temp gauge. The oil runs very cool while driving to/from the track, especially in cold mornings. Thinking about adding an inline thermostat, which seems not that popular. Wondering why?
I assume you mean a water/oil cooler? Certainly that would get the oil up to temp more quickly. I'm ok with a long-ish warm up time. I would just like it to maintain heat while driving to/from the track under light load and not plummet once I get on the freeway. An inline Tstat seems like the simplest solution?
I am not 100% sure if the 420R comes with a radiator cooler up front but if it does you could just blank it off for the road. However this will help solve your problem https://www.burtonpower.com/cosworth-modeen-oil-co...
But as said if the dry sump tank and sump are radiating more heat than is being put into the oil it will always be running cool. Ideally 60C is wanted, but the tank will always be cooler than the oil circulating in the engine, so I would suggest 50C+ is nothing to worry about for gentle road driving.
But as said if the dry sump tank and sump are radiating more heat than is being put into the oil it will always be running cool. Ideally 60C is wanted, but the tank will always be cooler than the oil circulating in the engine, so I would suggest 50C+ is nothing to worry about for gentle road driving.
I have the newer design oil cooler (mounted below the water radiator). I also have the 420R race style nosecone, with the separate vent for the oil cooler. On cool mornings, I do block off this vent. I can't really block the cooler directly, as I have a pusher fan. My temp sender is in the oil tank (after the cooler) and generally shows around 120F/50C when cruising on freeway. However on cold AM drives to track in Feb, I saw as low as 106F/41C for a stretch (even with the vent cover on). I figure the oil is significantly warmer in the engine, but still a bit unnerving to see those low numbers.
I agree that the oil as it flows through the engine will clearly warm, but I'd not be wanting to put 40 degree oil into the engine. The simplest way is to blank the oil cooler as has been said. I assume all the oil flows through the cooler so as well as a thermostat, it'd need a bypass. That adds up to quite a lot more plumbing with its weight and complexity which I assume is why it's not a popular solution.
I've got a dry sump 2.3 Duratec with a custom oil cooler mounted high up, Mocal thermostat and temp sender in the oil tank. Oil temps on the road are always quite low and takes ages to warm up. I probably see 40-60degC once warmed up depending on the ambient. The thermostats generally allow a 10% bypass even when closed, so will still send some oil to the cooler. Blanking my cooler off makes only a very small difference(thermostat should be closed). The biggest delta I've seen was putting some insulation around the dry sump tank. I experimented with a sheet of closed cell foam wrapped entirely around the tank with cable ties. This probably gave me 10-15degC improvement. It was fine for a couple of evening trackdays, but needed to be removed at Spa when the oil temps started to rise and ultimately degraded the foam.
The above comments regarding temp sender location are very relevant. I'm used to reading engine out temp, so it takes some adjustment.
The above comments regarding temp sender location are very relevant. I'm used to reading engine out temp, so it takes some adjustment.
4packet said:
I've got a dry sump 2.3 Duratec with a custom oil cooler mounted high up, Mocal thermostat and temp sender in the oil tank. Oil temps on the road are always quite low and takes ages to warm up. I probably see 40-60degC once warmed up depending on the ambient. The thermostats generally allow a 10% bypass even when closed, so will still send some oil to the cooler. Blanking my cooler off makes only a very small difference(thermostat should be closed). The biggest delta I've seen was putting some insulation around the dry sump tank. I experimented with a sheet of closed cell foam wrapped entirely around the tank with cable ties. This probably gave me 10-15degC improvement. It was fine for a couple of evening trackdays, but needed to be removed at Spa when the oil temps started to rise and ultimately degraded the foam.
The above comments regarding temp sender location are very relevant. I'm used to reading engine out temp, so it takes some adjustment.
I was aware of the oil bypassing the thermostat when closed, but I would have thought it would still keep temps up MUCH better than that. It sounds like your temps are similar to mine without a thermostat, so I don't think I'll be going that route. I could do a oil/water cooler, but then I'd be giving up ultimate cooling capacity - the question is whether or not that is needed. I don't want to have cooling issues on a hot trackday. There are a reasonable number of these setups running around, and I don't hear a bunch of tales of wiped cams or other issues related to cold oil, so maybe I'm worrying for nothing...The above comments regarding temp sender location are very relevant. I'm used to reading engine out temp, so it takes some adjustment.
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