Rebuilding another 455 olds, and I want to know if I buy a high volume oil pump if I have to buy a bigger oil pan?

My machinist tells me it is a myth, and the high volume oil pump will not suck the stock pan dry.

Looking for better oil pressure than 10 psi... That is too low to me.

Need some advice.
Thanks

 

My all stock 1970 455 sucked the pan dry a couple times cruising down the highway at 3000 rpm or so in about 6 miles and the head drainbacks were clean. Thats why I'm rebuilding it now!! There r things u can do like open the oil drainbacks in the head but I hear u have to b careful not to cut into the water jacket, get oil restricters to keep excessive amounts of oil from going to the valves and collecting under the valve covers, I think thats the main problem but I'm no expert. I am putting a windage tray, crank scrap and enlarging the oil pan to hold hopefully around 7 quarts. Do u really want to chance it with a new motor?? I've got it apart so I might as well put it back together with as many safty features as possible.

What rpm r u turning to make 10 psi? Its probably cool at idle. In 100 degree heat sitting at a stop light I have had as little as 8 with my 403 but as soon as i touch the gas it shoots up to 40-45.

 

I have a Milodon HV oil pump and Milodon deep sump pan on my 455. I didn't install restrictors in the 455. I've also heard you shouldn't run a HV oil pump without a deep sump pan. IMHO, it is worth the $230 for the deep sump pan. If you decide to get a deep sump pan buy the Milodon one, not the Moroso one. I started with a Moroso because it was $20 cheaper and aluminized steel instead of irridited. I went through 3 Moroso pans that leaked from the drain plug before I paid extra to get the Milodon.

 

Go with the bigger pan with the hi volume pump us a windage tray as well it keeps the oil from foaming. Think of the investment you already have in the engine. You won't be sorry. I run 20 lbs at idle hot and 45 on the road push it hard and it goes to 50 lbs

 

Thanks for the advice guys.

So deffinitley if I got High volume oil pump, get the mildon oil pan 7-8 qt or so.

Question, is a normal oil pump and only about 18psi, running, and about 4 psi idle enought to protect the motor, or is it wise to spend the extra put more oil in it and have more psi, to protect the motor,"investment"?

 

A normal oil pump and oil pan should be fine unless you are racing the car or revving high rpms. I only put a HV oil pump and deep sump pan on my Olds because I wanted to.

 

i have a high volume 20% bigger pump and the stock pan on my 1970 98 and iv never sucked the pan dry. i did clean out the oil drainbacks in the head before installing but didn't make them any bigger. the oil psi increase makes me feel so much better too. i have a psi gauge in my car that i check if i where to drain the pan id see a drop in oil psi and iv never seen one, im not conserved

 

I would not be comfortable with oil pressures that low. It sounds like you have excessive clearences somewhere in the system, which could include the oil pump gears and cover. You should want 45psi minimum at cruise.

Unless you find that the oil pump you've been using is bad, a high volume pump will be what you need to help compensate for large clearences. And if that doesn't work, you'll need to re-machine to get the clearences where they need to be.

A note on the oil pans... a 7 qt pan's sump will hang flush with the bottom of the cross member. An 8 qt. will hang below the cross member about an inch, exposing itself to the asphalt on large dips and bumps in the road. Nothing like the sickening sound (and feeling) of your oil pan bottoming out on the street to make your b-hole pucker. Been there... swapped to a 7 qt.

 

So far I haven't bottomed out the oil pan on the driveway or a speedbump. I have the 7 quart Milodon pan.