Research carefully. Rick. All Chevrolet small time engine builders I know use the factory GM bolt in oil filter adapter bypass valve. Its discontinued by General Motors. Available new aftermarket by Dorman. Push down on the disc valve with a small screwdriver. Feel spring preload. Not sure of Blowoff pressure specs. On Pontiac, Olds,& Buick V8 engine it only takes a few pounds pressure to open. Chevrolet seems to use a stronger spring to seat phelonic plastic disc tighter. Likely going to use an aftermarket Moroso billet aluminum oil filter adapter with no bypass valve on my 410.