If you are not using a cooler then leave the center valve out completely. Just finished up one yesterday. Mercruiser 454. If you leave the center valve in the oil has to go off to the side, through the passages that normally go to the cooler and then back to the center. You can trace the route yourself. Leaving it out gives a straight shot from the filter into the engine just like every other Big Block. A lot less restriction.

 

Hey Bill, I have a question on your recommendation. The "A" port bypass valve is a 30lb valve. The "B" port (Center) bypass valve that I read that was recommended and what I purchased is a 10lb valve. My question is this; The rating on these bypass valves, are they oil pressure lbs? If so, does this mean that if my oil pressure is above 10 lbs the oil will flow through? I don't know when my oil system will ever be below 10 lbs. With that being said, does this mean that if I put the 10 lb bypass valve in place, then could it act like a check valve and hold oil up in the galleys and give some resistance for the oil draining down into the filter? Or otherwise, if I leave it out, will that enable the oil to drain down faster?
Thanks in advance for your feedback.
Brett....

 

By the way, it is not a "check" valve. It is a bypass valve so the oil can get into the engine if the oil cooler gets clogged up

 

Okay Bill. Thanks for the knowledge. I'm building this to replace my 396. It is just a street engine. Let me ask you this; Would you recommend me using a cooler and if so, do you have a suggestion as to which one?

Thanks,
Brett.....

 

The only engines I have had coolers on are the Marine Big Blocks that I do. Personally do not see a need for it one on a street engine in a car. Nice looking engine !

 

Brett,

To answer your question yes the 10 lb rating means that ten lbs of pressure will open that valve and allow it to flow but ..........
The issue is not the pressure for the center valve, it is the restriction to flow. You are worrying way too much about the oil supposedly draining back to the filter etc. I would be more concerned with any restriction to flow into the engine. Think of all of the traditional Chevy V-8s. They do not have any type of "check" valve in the oiling system. It simply is not an issue.

 

Bill,, Thanks for responding. I'm sorry it seems like I'm worrying, but I'm just reaching out because I don't know and you do. I will not put it in. I just wanted to confirm. That's all.

Thanks,
Brett....

 

No problem. If you dont ask you will never learn