Block prep, oiling mods...

[scott foxwell]

I've just about got my block done but I've read mixed opinions on one certain oiling mod so I thought I'd get some input here. Jim Dove's site and some others say to drill the passage from the #2,3,4 cam journal to the main oil galley out to 5/16" using the holes in the main saddles as guides. Some say don't do this, that it's not necessary. Seems to be a reasonable mod to me. I've done all the others except that, and drilling the main oil galley that runs the length of the block to 7/16. I did open the feed hole to 7/16" that runs diagonally across the front of the block . Everything is tapped for screw in plugs, I did the .50" hole to the oil pump, opened the pump feed hole, matched the bearing holes, etc.
TIA

[blykins]

I have never done that.  I wouldn't want to make that area any weaker than it already is. 

I've never opened the main oil galley up either.   People under-estimate how much oil the factory holes can flow. 

[jayb]

+1 on Brent's advice, drilling that passage out won't help oiling any and it will weaken the block in an area where they are prone to cracking at #2 and #4.  Also IMO, there is a lot of "questionable" info on the Dove site...

[Ranch]

What size engine?
What is your intentions for this engine, stock, nice street a little track, full race?
A bigger oil pan for anything more than stock, even then you should overfill by a qt. just in case. Good job on taping for the pipe plugs.  A HV oil pump is nice insurance but then you should definitely use a deeper oil pan. Match the main bearing to saddle oiling holes, a little dressing at the around the oil filter mount won't hurt and a CJ oil filter mounting bracket  Maybe tap the heads for 3/8-16 set screw rocker restrictions.
 All those 'drilling' oil mods you read about are more for the track guy, anything less than track to me is a kinda over kill. ...JMO

[scott foxwell]

Engine is a 390 +.030, ~450hp, 6000rpm, hyd roller, hot street deal. Going in my 67 Fairlane.
I know the blocks will crack form the mains to the cam tunnel, but never heard of one cracking from the cam to the oil galley. It doesn't make sense to me that you have a 1/4" hole feeding the cam bearing, then feeding a 5/16 hole to the main. To me, that makes the 1/4" hole between the cam and main oil galley a restriction to the main bearings. It would be better if the cam bearing holes were 5/16 and the main saddle holes were 1/4", but it is what it is. I have a Canton pan, pickup and windage screen, HV pump, ARP shaft, will set bearing clearances accordingly.

[blykins]

Skip the high volume pump, run a standard volume....

[scott foxwell]

Skip the high volume pump, run a standard volume....

If this was a race deal where I was looking for every last few HP I probably would.

[fekbmax]

+2 on not drilling the oil feeds from the cam journal's back to the main oil feed.
However i have and do always run a long 7/16" well lubed bit through the center main oil galley. Its more of a clean up than anything else.  I have seen many times for there to be some restrictions in this area. Especially  if you happen to sink a plug to deep when blocking off the lifter galley's.
As far as Dove's info goes, i believe there could be some questionable info there but i look at it more so as out dated or not updated.  It's the very same info and write up as that what appears in his earliest loose papper catalogs from 25 years ago. Things have changed and evolved with more and more excellent FE engine builders now. We always learn right ?? I think there is still some good info there as well. I remember when Dove and FPP were all there was for the FE faithful.  Like them or hate them, those guys played a huge part in keeping the FE alive back then. Now we have a fat handful of great FE engine builders and more parts to work with, + a guy like Jay that develops some awesome parts himself.
Of course all this is just my opinion. 

[blykins]

Unless you're running loose clearances, I don't see the need for a HV pump.  Customers like to see 9000 psi of oil pressure and the HV pumps usually offer a little more oil pressure than the standard volume pumps, so it keeps the complaints down. 

However, when I have a free-reign choice, I will go standard volume.  25 psi at idle, >60 psi at 6000.  It's sufficient for almost everything out there. 

[scott foxwell]

+2 on not drilling the oil feeds from the cam journal's back to the main oil feed.

I'm still not seeing the down side of this, especially when 2 & 4 also feed the rockers.

[Heo]

The downside is that the block is prone to crack in that area
even undrilled so drilling is making it worse i been told....

[blykins]

Just doesn't need to be done.   There's enough oil flow there to supply what's needed.  The supply to the rockers are indeed fed from there as well, but check the hole in your head gasket from where the block feeds the head.  It's necked down there.

That whole area is just a spot I wouldn't be drilling on.  It's not uncommon to get cracks (or possibly even some core shift that weakens things) on the passages that lead from the cam bearings to the decks, then you get oil in the water. 

[blykins]

If you want to try something new, I have a fully enclosed cam tunnel for an FE.....

[HarleyJack17]

"I'm still not seeing the down side of this, especially when 2 & 4 also feed the rockers.

Scott, you have some good ideas but on the point being made concerning feeding to the rockers: there is no issue factory wise here. The FE "over oils" the rockers. Maybe not if everything was perfect but that is not how it goes. Most rockers are "loose" on the shafts causing a lot of oil bleed and pressure loss. This is why head gaskets have smaller than factory oil holes and most even reduce that down to .065-.075 in the head. If you take an FE and prime it with the valve covers off you will see this.  Don't get wrapped up in the size of the feed hole...that is one direction.  The "reserve" is the entire shaft.

You can limit rocker oiling or modify the drain back. Modifying the drain back can lose strength in the head/bolt depending on how its done/how much is done, so limiting the top end oiling is the best path. Adding a HV adds even more oil/issues if no other modifications are made.  As the engine wears the rockers get even more loose.
My own personal theory: the is cause for the low oil pressure/main bearing issues in older, non rebuilt FE engines, is the wearing of the rockers and the bleeding of oil in the top.  This causes pressure drop and loss of flow to the mains. Fluids take the path of least resistance. Anyway, you are getting some good advice from some folks that have built a lot of them. Good luck on your build.     

[scott foxwell]

Thanks HarleyJack...I understand the issues with oiling the top end. I'll be installing restrictors in the heads but honestly, I don't mind a lot of oil upstairs. The valve springs love it. As long as there is an adequate supply for the rest of the engine...
Drain back is something I'll look at.
My thought on 2&4 feeding the rockers isn't that the block needs drilling because of that per se, it's that there is an extra demand on that oil passage, however small or restricted, robbing oil that's not getting to the mains. Whoever designed this system where the feed from the main galley to the cam brgs is 1/4", and the feed from the cam bearings to the main bearings is 5/16... either didn't understand fluid dynamics, or didn't care, or there's a reason I'm not seeing. Maybe it's picking pepper out of flyshit but that's just how my mind works. I'll go on the advice of the strength issue...although that doesn't make sense to me either, but I'll trust the experience of others here.
Thanks for all the input.