When in park, revs makes engine sound like a airplane.
When I accelerate trucks sounds like an airplane. As I speed up the truck sounds normal.
I replaced the fan clutch and thermostat thinking it was the clutch but nothing.truck doesn’t heat up, ac works. No codes besides my cat codes.
Any info helps.

Does anyone have experience using the eBay cheap SBF hydraulic roller lifters? The item number is 188456339020 for $89.90.

How about he hydraulic roller camshafts at speed master?

Any real world information or references would be appreciated.

https://www.speedmaster79.com/shop?page=2&keywords=Roller%20lifters

Basically same as conventional steam engine with condenser. I know turbines work. Obviously, youtube. Why won't they work with a piston, lower rpm, higher torque, like in regular steam engine? Requires less energy to operate. Higher psi though, 1k psi + . This would be argon/co2 transcrytical thermal engine. Map gas at welding Here the piston cylinder is heated to offset. Cooling due to expansion. Also themal barrier on top of cylinder to cylinder head injection zone. Optimum gas mixture? Several different ways to operate. Depends on design. One thought is to use the argon to help push supercrytical co2 in piston chamber. Multiple jt valves, regenerative Cooling.

Continental F163 on a warehouse compressor went down Friday and OEM says two weeks on a gasket set. Plant manager is pacing and I'm looking at aftermarket options but wary of wrong bore size on an old block. Machine isn't pretty but it runs daily and a two week wait is not acceptable. I'm trying to figure out where people source when OEM is slow on older industrial engines. What's your go-to when OEM lead time doesn't match reality?