I'm thinking to buy a high volume oil pump. Does the additional volume for the price "really" make a difference? I can't find anything other the "up to 25%" more volume. Who know's what the exact volume is? Any recommendations?
A high volume pump really isn't necessary for a low RPM Jeep engine, but it won't hurt anything to have one. Just make sure you keep your oil topped off because I have seen them empty a stock oil pan on a small block Chevy engine with a stock capacity pan. This was in a higher RPM circle track engine where the stock pan had to be used by rule. Be sure that all of your oil return passages are not blocked with sludge or crud too. Any blocked oil returns and you'll soon find out where your gasket sealing is minimal, especially on the valve cover. For the record, I normally do use a HV oil pump in my engine rebuilds, but for this type of application I would use either one. One other thing to kkeep in mind is that because the pump is pumping more oil, there will be more load on the oil pump shaft. I can't recall what type the 258 uses, but if there is a hardened or heavy shaft available, I would invest in that too. I know the stock shaft on a SB Chevy will not hold up under heavy use with an HV pump.
Chris
"Especially the valve cover"???
The valve cover is not a pressurized gasket, that is, the oil is not pressurized at that point. I agree completely that the VC gasket is a weak spot, but I can't see how this would be made worse by the oil pump, unless you are suggesting that the sheer volume of oil on the top of the motor will find its way out if the gasket is not sealing well.
In order to have a vacuum in there at times it still has to be a pressure chamber. Negative pressure and positive pressure both need a basically sealed container.
Mike
"L.W.(ßill) Hughes III" wrote:
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.