Drilling oil galleries and oil return holes?

[69_340_GTS]

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.

Tried the flat adapter plate and the short filter with the TTI shorties. No way to get the filter off and on, no room. Ended up puting the 90° adapter back on.

 

[nm9stheham]

For anyone relieving the ports inside the pump: You had better take the oil pump relief valve apart make sure you did not get some particles in around it. If there is a residual particle there, it can jam the relief valve open and drop the oil pressure.

 

[nm9stheham]

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

Sorry to not be clear. I was thinking you are drilling out the holes from each main up to the passenger side lifter gallery. Those are the oil supply passages from the passenger side lifter gallery INTO the main, rod, and cam bearings.

The #1 main hole from the passenger side lifter gallery supplies both the #1 main and the #1 rod, but also there is another passage from the #1 main saddle back up to the driver's side oil gallery. All the driver's side lifter gallery oil goes through that area so adds a fair amount of flow into the #1 main. So I drill out both passages from the #1 to each lifter gallery.

 

[ValiantOne]

Sorry to not be clear. I was thinking you are drilling out the holes from each main up to the passenger side lifter gallery. Those are the oil supply passages from the passenger side lifter gallery INTO the main, rod, and cam bearings.

The #1 main hole from the passenger side lifter gallery supplies both the #1 main and the #1 rod, but also there is another passage from the #1 main saddle back up to the driver's side oil gallery. All the driver's side lifter gallery oil goes through that area so adds a fair amount of flow into the #1 main. So I drill out both passages from the #1 to each lifter gallery.

Okay that makes sense. Since #1 supplies the drivers side lifter gallery, you want more volume there. What size do you drill them too?

 

[yellow rose]

Okay that makes sense. Since #1 supplies the drivers side lifter gallery, you want more volume there. What size do you drill them too?

9/32 (.~.287) is big enough. I don't drill the feed any bigger to the drivers side lifters. They get more then they need.

 

[nm9stheham]

9/32 (.~.287) is big enough. I don't drill the feed any bigger to the drivers side lifters. They get more then they need.

If the lifter bores were worn, then it would be a good idea to do so. And use the HV pump with all of this IMHO. The lifter bore wear is all over the map on these engines anymore.

I agree on the drill size. But I went to 10/32" (5/16"). I drilled carefully with that bigger size!