lifter galley crossover tube
I'll say it again. I don't care how fast the oil is going. It will make the turn. I know a guy who was paid big $$$$$$ in 1969 to try and fix the oiling issues Chrysler was having. The factory gave him 8 or 9 blocks, I can't remember how many heads and MONEY. I was having issues with my junk and the topic came up at lunch one day.
He said the thought from the Chrysler was oil velocity. They screwed with it for months. The only thing they learned was it has zero to do with oil velocity. And the crossover tube was a waste of time.
Duane, I have no issue with you bringing in other brands. As you said, I did it, with good reason. What set me off was moving away from the era we are discussing. What they are doing in 2017 has ZERO to do with what they were doing when they designed this stuff.
No matter how much you want to deny it, correct oil timing is ~70 degrees ATDC. Done and settled. If the factory moved the oil feed holes in later stuff, it is purely from a cost of manufacturing point of view. Had nothing to do with engineering. Just like a front drive oil pump. It isn't better. It's cheaper.
As for cross drilled cranks...you need to slow down and READ what I WROTE and not make up what you think I said. I NEVER have said, nor have I ever been an advocate for cross drilling a crank. If and that's a big IF the oil timing is correct, there is never a need to cross drill the crank. Ever.
However, if the oil timing is off, and you can't move the feed hole in the crank then you have no choice but to feed the oil in from the bottom and cross drill the crank, so the oil feed hole in the crank is lined up with the feed hole in the crank at ~70 degrees past TDC. That's why you cross drill it. So the oil holes line up at the correct time.
You can feed the oil anywhere you want. Noon. Six. Nine. Three. Eleven. Doesn't matter. As long as the oil feed hole in the crank lines up at the correct time. You can argue that all you want, but you'll still be wrong. It's settled engineering for high speed engine oiling. Yes, you can make it so you have the oil going to the mains first. That's how it SHOULD be, but many, many miles and passes have been made in chevrolets without priority main oiling.
In fact, I know for a fact, the NHRA BB/A national record holder in about 2004-2005 was spinning a bit over 10k, with a blown gas deal and he didn't have priority main oiling. I know. I machined the block and did some of the port work on the heads and the first valve job he set the record with. I also was able to look at his data after the runs. He was shifting at 10,200 and crossed at just over 10,600. As he kept lowering the record, the RPM kept going up. He last record holder was based on a Brad Anderson block.
That was a 2900 pound car and no more than 310 inches.
So you can argue all you want for oil velocity, where the pump is mounted, pulling oil off at the cam bearings, and anything else you can think of, but it all comes down to oil timing.
If you aren't turning over 7500, oil timing isn't as big as issue as it is at 8000 and above.
When I get a minute, I will go out and make a video that hopefully explains it better.
Oil timing is all that matters. If that is correct, everything else is superfluous.
Welcome back Yellow Rose.
I wanted to respond to your recent post and ask a few questions.
As you can probably tell I am a believer in the velocity issue and can appreciate that some are not.( Mostly race engine builders)
Firstly to clear up a few things.
I fully understand the reason you are proposing to cross drill to the crank and the theory on how it would improve oiling to the rods.
I do not agree that it would,but I understand the theory and the reason.
If you are not normally a proponent of cross drilling ,you could have just said that in the first place. It was not my intention to start talking about newer engines. I too only brought them into the discussion to make a point. That being that even though you feel that
The older Chev engine has a better oiling system than the la engine( which it does imho) it too had it room for improvement.
Not all changes to a newer engine are for cost reduction. Many are for ease of service in case of a problem for the dealership.
We build thousands of engines per week. Reliability is the name of the game or you lose customers. When you build thousands of engines failure trends do show up.
Secondly I have never said that the older small block Chev has priority main oiling. I also never said that the galley in the centre galley in a Chev is the "main " galley. I said exactly what B3 said that that galley does not feed the lifters. I just used different wording.
I only said that it is the galley that feeds the mains. I did not say it feeds the main bearings first, just that it feeds the mains.
The small block Mopar with a few mods oils the main bearings first and functions very much like priority main oiling imho. Not the Chev.
Now if you do not mind can I ask some questions.
Can you expand on how the 70 degrees after top dead centre is arrived at. How do you get that exact number. After all we are firing the combustion mixture at approx 35 degrees before top dead centre. There is already a downward combustion force well before 70 degrees.
Second question, Do you not believe that the oil groove in the upper half of main bearings would give enough pressure to support the rod bearings even if the oil hole is not in direct alignment with the hole in the block? In other words the oil hole in the main is exposed to oil pump pressure anywhere along that groove. And with full grooved mains everywhere.
If you look at the advertisement that I posted from Scat(hard to read) what I wanted everyone to look at was not the cross drilling or straight oiling parts but the posted clock positions of the entry and exit points where they drill the rod oiling hole relative to the main bearings.
I have acknowledged in some previous posts that your oil timing issue has merit. I am aware of it. I just do not understand how you arrived at the position that you think they should be in and your method to fix it. But I agree with the issue.
Also I agree that the issue may be more of a problem on an original
Crank. I posted that only aftermarket cranks probably would have these newer refined
oil hole positions.
It was not my intention to upset you or feud with you.
Just exchanging views here nothing more.