Oil Cooler Sizing

[bassracer]

Looking for recommendations on how to approach determining the correct size for an oil cooler - at least to start. 1995 Van Diemen RF95 - The car has been converted to Honda but never run on track to know baseline oil temps. Would like to package behind radiator left side which I believe is the primary Radiator plumbed in series. Thanks!

[Raceworks]

If you can get the water temps down enough you shouldn't need an oil cooler. Right now we're 190-210F on water temps and 250-270 on oil temps.

You'll want to open the side-pods opposite the radiators with a roughly 4"x12" opening. Heat shielding on the oil & water lines helps where hot & cold water pass near each other or where the exhaust is close to the oil line from the sump tank. A thermal coating (not wrap) helps a LOT on the exhaust.

If you still want to run an oil cooler go with something relatively small (12 rows or less) like the 10-13 row Setrab coolers (the 8" long "1-series") will do the job fine. For a couple years on the Spectrums I ran one of the larger Setrab coolers (16 row, 12" long "6 series") but that just BARELY fit inside the left sidepod and tended to rub on one of the fittings.

[mboian90]

Brandon,

My car didnt have an oil cooler when I got it in 2015. In my extensive road racing experience of 3 race weekends starting this year, I usually see ~170-190F water temp and 270-275F oil temp (measured in the port on front right of the pan below the -10 oil inlet). This is with ambient in the 100-105F range. When I remade my dry sump tank this spring I put a temp sensor in it and it has been running in the 240F range, it makes a great seat warmer in those cold Texas summers. I havent decided yet if I will add an oil cooler, the Honda manual lists 284F but doesnt give a location.

System capacity is ~5.5 qts and oil pressure runs ~70 psig while on track. I also did some improvements to the cooling system in 2020 so I am assuming the car ran the same or hotter oil temps from 2010-2015.

Matt Boian