[HWYSTR455]

My understanding is that 230-260 is the target baseline (operating range), and 300 is the limit.

If you're using a remote setup, I would be curious to see your line routing at the block, if it's close to the header, you may be causing an overheated condition.

As for coolers, one place you don't want to mess around and/or cheap out is an oil cooler. Race quality (road race that is) stack plate type are the go to, and at your temps a small one would be fine. Earl's is a very nice, high quality, stack plate cooler(s).

https://www.holley.com/products/cool...ssion_coolers/

Oil systems should also use contoured/radiused fittings throughout.

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