Drilling oil galleries and oil return holes?

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ValiantOne

ValiantOne

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The engine is a 5.9 Magnum.

In another thread a member suggested:

"I would also add , 1/8" drill between the lifter pedestals to aid oil return, 3/16"long drill from main bearing journal to lifter galley for more oil volume to the mains (it is step drilled from factory) and debur the casting flash."

I am wondering if any of you have done this. If so, do you think it is worthwhile?

Also, if I open the stepped hole from the main bearing saddle to the cam bearing bores up to 3/16, will I have to go with a high volume oil pump?

mail journal.jpg


oil return holes.jpg
 
I add drainbacks and drill the main feeds in everything. The enlarged main passages have nothing to do with needing more volume from the pump. Bearing clearances and type of bearings have everything to do with needing more volume. If you are running stock spec clearances (up to .0025") then a stock volume pump with a high pressure relief valve is fine. If the clearances are bigger than .0025, and you're running full groove main bearings, then the HV pump will be needed depending on the performance expectations. Consult your builder on the clearances prior to anything being machined.
 
moper said:
I add drainbacks and drill the main feeds in everything. The enlarged main passages have nothing to do with needing more volume from the pump. Bearing clearances and type of bearings have everything to do with needing more volume. If you are running stock spec clearances (up to .0025") then a stock volume pump with a high pressure relief valve is fine. If the clearances are bigger than .0025, and you're running full groove main bearings, then the HV pump will be needed depending on the performance expectations. Consult your builder on the clearances prior to anything being machined.
Click to expand...

When you do drainbacks, do you do them in the same areas I have circled in the photo?
 
No. I go outside the "paired bores". Those areas seem to pool the most oil. You don;t need to drill 5 new holes in the valley. Deburr whats there, and add a few others where the oil pools.
 
Don't forget to give the rear main cap some help at the sharp corner, and get rid of the 90* adapter.
With these mods,and some others, my 367 has been running up to 7000/7200 regularly, since 1999. The last time I did a refresh was 2004. The used bearings went back in, and now have over 100,000miles on them.
 
AJ/FormS said:
Don't forget to give the rear main cap some help at the sharp corner, and get rid of the 90* adapter.
With these mods,and some others, my 367 has been running up to 7000/7200 regularly, since 1999. The last time I did a refresh was 2004. The used bearings went back in, and now have over 100,000miles on them.
Click to expand...

I'll go have a look at the rear main cap. I'm guessing you mean soften the corner a bit with a die grinder?

As for the 90* adapter I believe my exhaust requires it. I couldn't make an oil filter screw on without the adapter. Is there something I don't know here?

Thanks,

CE
 
If you want, you could tap the block itself and run oil lines directly from the block to a remote filter block housing.

A simple Mr. Gasket relocation kit should do the trick. Purchase 45* line in and out fittings to route the oil lines away from the headers even more and port the aluminum adapter block to smooth the oil path within.
 
Yeh that's it; 2 less 90*s with their oh-so-sharp corners. Seems to work ok for the factory. And it may still for HO, but to my way of thinking I was having none of it. With TTIs there is plenty of room for a shorty filter in there.
 
What is the purpose of this engine? How hard are you going to run it that you feel these modifications are even necessary?
 
AJ/FormS said:
Yeh that's it; 2 less 90*s with their oh-so-sharp corners. Seems to work ok for the factory. And it may still for HO, but to my way of thinking I was having none of it. With TTIs there is plenty of room for a shorty filter in there.
Click to expand...

Cool. Running stock 340 manifolds right now, but I'll keep that in mind. I do plan on adding TTI shorties in the future. Maybe the small filter will work with them too.
 
IQ52 said:
What is the purpose of this engine? How hard are you going to run it that you feel these modifications are even necessary?
Click to expand...

I don't "feel" anything. It is the reason I am asking what these mods do, has anyone else done them, and do they think it was worth it. I know zippy about any of these oil mods.

Intended use is hot rodding, cruising on the street, and a track day/auto cross day several times per year.
 
yellow rose said:
I've seen it done but I think it has zero value.
Click to expand...
I believe this probably correct and that this modification (oil holes in the lifter galley) will actually have a negative effect. I want the oil running to the ends of the block and not down on the crankshaft adding to the windage problem.

Drilling out the main bearing feeds is probably not necessary on the Magnum block as the #2 & #4 cam bearings are not supplying oil to any rocker shafts.

I do recommend the main cap modification suggested.
 
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IQ52 said:
I believe this probably correct and that this modification (oil holes in the lifter galley) will actually have a negative effect. I want the oil running to the ends of the block and not down on the crankshaft adding to the windage problem.

Drilling out the main bearing feeds is probably not necessary on the Magnum block as the #2 & #4 cam bearings are not supplying oil to any rocker shafts.

I do recommend the main cap modification suggested.
Click to expand...

Interesting. I hadn't considered the additional windage. I wonder what volume of oil actually sits up there anyhow. I think the pan I am using (baffled kevko) holds an extra quart anyhow, over stock.

I'm definitely going to look at that cap today.

Thanks,

CE
 
Well whatever sits in those pockets, it is constantly moving. Some comes in and some goes out. Hopefully it moves on down to the back.But no matter where it goes, the crank is probably gonna beat it up as it moves towards the pan. It will maybe fall down into the windage, get beat up for awhile bounce off the windage tray, go around for some more misery, but eventually it will end up in the sump.
To my way of thinking I though it might as well do some good on it's way, so I drilled those little holes in those pockets you're talking about, hoping some of it would get onto the cam-lobes. Well I haven't wiped another cam after doing that............
See, I spend a lot of time at low rpm, and even below low rpm. Sometimes at 500/550 idling/parading around.And I run the hi-volume pump. So, after wiping one cam, I needed to come up with ideas. The holes were one of 'em.
And After I figured out that my little cam pulled hard even way past it's power peak,I run it up there just about all the time. I mean it hits 65mph at 6900, in first-over, so.......GO!
Well they told me SBMs die when you do that all the time. So I researched why that is. It seems,mostly this happens when you suck the pan dry, as in running low on oil. I blew up a couple of 340s doing that. So on my new project, I installed a 7qt pan on it and run 5 or sometimes 6 qts in it. Then I ground drainage channels in a number of places where I saw oil pooling. So now there is always plenty of oil in the pan. It must be working cuz the engine now has over 100,000 miles on it.
 
Not knowing the stresses in the block at the lifter bores, and not seeing any big benefit, I don't think I would ever bother with those holes by the lifters. The oil quantity there has to be pretty small.

The enlarging the passages from the mains to the lifter gallery I DID do. It will put a little more pressure to each bearing, and thus keep the flow a bit better to the mains and rods. The front bearing holes need the most attention, as that is the crossover path for the oil from the passenger side gallery to the driver's side. Also, the passages out the oil pump and to the filter and back up to the passenger side lifter gallery.

Just drill those long holes at a steady RPM, not too high and not low to avoid chatter on the bit, and not too much pressure. Pull out often to get the chips out. Read up on drilling cast iron.
 
I understand your rationale IQ - but I have to respectfully disagree. These are street engines. Windage in these cases is not a big deal, and in fact will add to the oil the lobes get. I'd guess it's less of a power loss than a HV oil pump. Not every build needs a 7qt pan, scraper, and covers over the valley holes. In fact the vast majority don't.
 
nm9stheham said:
Not knowing the stresses in the block at the lifter bores, and not seeing any big benefit, I don't think I would ever bother with those holes by the lifters. The oil quantity there has to be pretty small.

The enlarging the passages from the mains to the lifter gallery I DID do. It will put a little more pressure to each bearing, and thus keep the flow a bit better to the mains and rods. The front bearing holes need the most attention, as that is the crossover path for the oil from the passenger side gallery to the driver's side. Also, the passages out the oil pump and to the filter and back up to the passenger side lifter gallery.

Just drill those long holes at a steady RPM, not too high and not low to avoid chatter on the bit, and not too much pressure. Pull out often to get the chips out. Read up on drilling cast iron.
Click to expand...


Now I am confused again about the passages to the mains. I thought the stepped holes I am supposed to drill run from the main bearings to the cam bearing area (not the lifter gallery). Do I have this wrong. There are three holes that lead down to the mains. I thought the stepped hole went straight up to the cam bearing area. The block is at the machine shop so I can't go out and look.

When you say the "front bearing holes need the most attention" does that mean mains 1&2? Or does it even matter if I do all of them?

Thanks,

CE
 
IQ52 said:
I believe this probably correct and that this modification (oil holes in the lifter galley) will actually have a negative effect. I want the oil running to the ends of the block and not down on the crankshaft adding to the windage problem.

Drilling out the main bearing feeds is probably not necessary on the Magnum block as the #2 & #4 cam bearings are not supplying oil to any rocker shafts.

I do recommend the main cap modification suggested.
Click to expand...

Do you mean matching the pump to the cap mating surfaces?:

I did this:

IMG_6998.JPG


IMG_6999.JPG
 
moper said:
I add drainbacks and drill the main feeds in everything. The enlarged main passages have nothing to do with needing more volume from the pump. Bearing clearances and type of bearings have everything to do with needing more volume. If you are running stock spec clearances (up to .0025") then a stock volume pump with a high pressure relief valve is fine. If the clearances are bigger than .0025, and you're running full groove main bearings, then the HV pump will be needed depending on the performance expectations. Consult your builder on the clearances prior to anything being machined.
Click to expand...

Bearing clearance will decide high volume pump or not when using full groove, not bearing style. You can tighten the front main to .0019-.002 , the rest .0024 and run the rods at .002 ish , mine at lowest is around 35psi and goes about 70psi hot at rpm.
 
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moper said:
I understand your rationale IQ - but I have to respectfully disagree. These are street engines. Windage in these cases is not a big deal, and in fact will add to the oil the lobes get. I'd guess it's less of a power loss than a HV oil pump. Not every build needs a 7qt pan, scraper, and covers over the valley holes. In fact the vast majority don't.
Click to expand...
Seeing as you addressed this response to me, I will respond.

Okay
 
ValiantOne said:
What is the idea of running the first main tighter?
Click to expand...
Kinda like the end of the line, you dont want it too tight but the rest all pick up and in general main bleed won't be as bad aka reflecting in the pressure gauge better numbers if higher is better .
 
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