Hi, im building my 1966 400 engine.

Im triying to build a street car, I think around 300HP

In my oiling sistem I bought a new stock oil pump and I just add a new spring for increase the pressure, I have my stock oil pan and pick up, but Mondello also recommend to install oil restrictors (that I bought too)

I dont have any experience with oil restrictors, are they really necesary? I heard some people dond like them?

Im not sure how to install them and im worried that they can come out of its place and damage all the engine?

thanks for any advice

 

I'm no expert but i image they would back out and fall into the engine oneday also. take a look at http://www.oldsperformanceproducts.com/ they have some that are threaded.

 

Read the link below--asked the same sort of question some time back.
Can`t see the restrictors falling out BTW. -And from what the guys say, unless you are running an engine over 5000 rpm , and the engine is kinda stock , why bother.
MIKE



https://classicoldsmobile.com/forums...ary-where.html

 

I built my 350 5 or 6 years ago. I installed the restricters. You just loctite them in, no problem.

However you also need to notch the bearing shell as well otherwise they won't allow enough oil to the cam and lifters. Even with that I've had three different hydraulic cams as well as three different sets (brands) of lifters and Rockers, they all clattered.

Next time I'm just going to use a restricted pushrod instead. Seems to me to be a better alternative if you think about it.

 

First, there are different kinds of restrictors. The most common ones go in the passageways between the main bearings and the cam bearings. The worth of these restrictors is dubious, because on an Olds motor, the main galleries feed the lifters FIRST, then the main bearings, THEN the cam bearings. At that point the oiling is done. Also note that these restrictors will have exactly NO impact on the amount of oil going up the pushrods (since that oil flows long before the flow gets to the restrictors) and they will have NO impact on the lifters or rockers "clattering". They are popular because they are easy to install, not because they actually do anything. As for "falling out", that is physically impossible. The restrictors would need to pass through the small hole in the main bearings, past the bearing on the crank itself, and then they'd be loose. How this "eye of the needle" thing actually happens is another mystery. Finally, if you feel that restricting the oil to the cam bearings is mandatory, save your money and simply drill smaller oil holes in the cam bearings at a spot 180 degrees away from the extisting oil holes in the bearings. Now install the cam bearings with these smaller holes toward the crank. Voila. Oil restrictors for free.

The other kind of oil restrictor for Olds motors is the restrictor that goes in each of the sixteen lifter feed holes. These restrictors DO keep oil at the crank by reducing the flow to the lifters and pushrods from the main galleries. These restrictors require much more work to install and are thus not used as much.

 

Just as "Joe" said, his way is the one I use. I redrill the cam brg's with a .040 drill, I also drill and tap all the lifter bore oil holes for an 8/32 screw that is drilled with a .045 hole for solids and .055 for hydraulics. I'm not real sure if it helps, but I port match the #5 main cap to match the oil pump and I also inlarge the oil passage in the block from the main cap to the oil filter passage.

Gene

 

But I assure you, my name really is "Joe"...\

You've hit all the correct things, in my opinion. I assume you're using regular 8-32 setscrews? Do you have any problem drilling them? Locktite or some other method of retention?

 

[QUOTE=joe_padavano;71501]First, there are different kinds of restrictors. The most common ones go in the passageways between the main bearings and the cam bearings. The worth of these restrictors is dubious, because on an Olds motor, the main galleries feed the lifters FIRST, then the main bearings, THEN the cam bearings. At that point the oiling is done. Also note that these restrictors will have exactly NO impact on the amount of oil going up the pushrods (since that oil flows long before the flow gets to the restrictors) and they will have NO impact on the lifters or rockers "clattering". They are popular because they are easy to install, not because they actually do anything. As for "falling out", that is physically impossible. The restrictors would need to pass through the small hole in the main bearings, past the bearing on the crank itself, and then they'd be loose. How this "eye of the needle" thing actually happens is another mystery. Finally, if you feel that restricting the oil to the cam bearings is mandatory, save your money and simply drill smaller oil holes in the cam bearings at a spot 180 degrees away from the extisting oil holes in the bearings. Now install the cam bearings with these smaller holes toward the crank. Voila. Oil restrictors for free.




Thank you for the advice. I already bouth the mondello oil restrictors, so Im going to use them. now the question is: they have to be install in the vertical oil passageways between the main bearings and the cam bearings that are located in the block?

here is a link when you can see exactly the restrictos
http://www.mondellotwister.com/R-104.gif

the other questions is wich side goes first to the block?

 

It really doesn't matter, but usually you want to put the smooth end in first, just to make it easier to drive them in.

 

"Joe" I use a 8/32 screw 1/2" long. I have to drill a few of the lifter oil holes to make sure it does not interfear with the lifter. Drill and tap the oil holes and shorten the screws a little. I drill right down the middle of the screw, loctite it in.
Works for me, I have great oil pressure, 70 cold, 50 hot.

Gene

 

It really doesn't matter, but usually you want to put the smooth end in first, just to make it easier to drive them in.[/QUOTE]

Thank you Joe, now I have another question about oiling system on olds.

I read that olds have problems with oil return from the heads. And I read that is possible to correct this problem by enlarging the return oil holes on the heads and the block, they question is how much is the maximum diameter to enlarge those holes without having problems touching the water camera? is that a good Idea? are there any other ideas to solve this problem?

Im ataching 2 photos of the holes im talking about so you can have a better Idea.

http://uploader.ws/upload/200903/img440.jpg

http://uploader.ws/upload/200903/img439.jpg

thanks

 

No good on the pic's. Just says 403-forbidden

Gene

 

 

The links don't work for me either (though "403 - forbidden" must be a sign from on high... ).

I assume you're talking about the drainback holes in the bottom corners of the heads. At a minimum you should deburr the holes and radius the inlet side to help with oil flow.

 

I just add some pictures, if you can look at them, what im worried about is how much I can enlarge the hole without causing problems.

 

Where? The links in your post above still don't work. I would not enlarge the holes so much as smooth them out and radius the inlets.

 

In my opinion I would not put in resrictors of any kind. Those motors ran a long time and were some of the most durable with no resrictors. Watch out for the high volume pump as you do not want to run the pan dry. there is a lot of pro's and cons either way depending on what you are doing with the motor. Just my opinion
One thing I do not know for sure is whether or not the stock main bearings had oil grooves? Does anybody know?
I do run a 7 quart oil pan on my 455
I would also watch dealing with Mondello.

Tim
TIM 72

 

Thanks to all for the help, I already install the restrictors on # 2, 3 and 4 mains.