My take on the oiling system crossover tube for the small block

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mopardude318 said:
At the time I had a 90* oil filter adapter, which has a take off port there as well. That is the 2 locations which were used.
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So there is a 10 psi drop after the filter? Your line pressure is actually dropping as the rpm got higher which is not good. 37psi at 5,000 rpm is not good.imho
 
Duane said:
So there is a 10 psi drop after the filter? Your line pressure is actually dropping as the rpm got higher which is not good. 37psi at 5,000 rpm is not good.imho
Click to expand...

I'll put that 90* adapter back on and verify those readings tomorrow. That's all I can do because I was not there on dyno day. my brother was. Stay tuned. :)
 
mopardude318 said:
Ya know, I might be wrong about the 3/16" part. From what Doug over at Precision mentioned on the phone was that he does not use the high pressure springs, he uses shims with the stock spring to bring the pressure up. I'm sure he has his reasons of doing it that way. I am certain he does a flow/pressure test.
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OK, well if he does it, then it makes no sense to me for you to add any shims.

Edit: See my next post on this for my opinion on what the new pump will do.
 
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nm9stheham said:
OK, well if he does it, then it makes no sense for you to add any shims.

This may have been said: I don't expect you see any change unless your present HV pump is worn or has a lower pressure spring or a whacked out part. It will keep pressures up at the lower RPM's better if the clearances are tighter but the relief spring is what limits the upper pressure.
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I understand. At this point, I'm not expecting to see any changes either. But it's already on it's way, so once I get it, it's going on when I change the rear main seal. You'll be hearing from me. Lol.
 
Wanted to say Thanks for posting the videos. I am doing most the the GJ oil mods now and seeing you drill bit "walk" and ruin the block is concerning. I had planned to drill the mains to the oil galley with a 9/32" bit....is there a way to keep it straight to avoid drilling offline??? Is it better to have a machine shop drill these??? Thanks Guys!
 
Does anyone know what size restrictor would be required for mounting LA heads on a magnum block if it was constant oil feed instead of coming from the cam pulses?
Kinda like what Indy uses for the Big Block external rocker shaft oil kit.

Check this out.
Mis-stated flow at beginning of vid, 310/209 cfm sidewinders

 
Alex5280 said:
Wanted to say Thanks for posting the videos. I am doing most the the GJ oil mods now and seeing you drill bit "walk" and ruin the block is concerning. I had planned to drill the mains to the oil galley with a 9/32" bit....is there a way to keep it straight to avoid drilling offline??? Is it better to have a machine shop drill these??? Thanks Guys!
Click to expand...

As you can tell I'm a rookie but next attempt I will be using a 9/32 bit or smaller to start the hole straight.
Then I will step up a size.
Take it slow, double and triple check.
I also bought a few grinding stones to smooth the surface at the hole entrance so I can have an easier time starting the drill.
Just gonna de-bur it a little.

I flat out was in a hurry and went straight to the 5/16" bit which is taking out a lot of meat all at once.
My bad.
 
Duane said:
So there is a 10 psi drop after the filter? Your line pressure is actually dropping as the rpm got higher which is not good. 37psi at 5,000 rpm is not good.imho
Click to expand...
We can't automatically make this conclusion on the pressure drop; you gotta account for the possibility that the 2 separate gauges are reading differently; the one at the 'line psi' location just may be off.

Some SMALL drop at the normal oil pressure sensor point ('line psi' in the data) with RPM is to be expected. Once the pressure relief spring starts limiting the pump outlet pressure, then the pressure at the top of the passages into the passenger side gallery is subject to the flow through the engine; that flow gradually increases with RPM, and will drop the pressures into the gallery a bit due to flow resistance in the filter and the passages to/from the filter. The 'line psi' difference 3k to 6k RPM is -2 psi; seems pretty good to me.

OP, what filter are you using?

mopardude318 said:
I have a HV pump on the engine right now. Haven't done anything else to it, no HP springs, no shims. Stock out of the box Melling HV pump from Napa.
Take a look.
Precision Oil Pumps
Click to expand...
From the data for 'oil psi', it is pretty obvious that you have the 50-ish psi relief spring with the present HV pump. So if the new pump is shimmed up to around 70 psi, then you ought to see a big change.

I 'took a look' yesterday at that site.. it did not say anything to help understand this.
 
prochargedmopar said:
Does anyone know what size restrictor would be required for mounting LA heads on a magnum block if it was constant oil feed instead of coming from the cam pulses?
Kinda like what Indy uses for the Big Block external rocker shaft oil kit.

Check this out.
Mis-stated flow at beginning of vid, 310/209 cfm sidewinders

Click to expand...

I assume you are doing something to provide the oil passages to the LA head feed passage that does not exist in the Magnum block? If so, then the restrictor sizes that I have read if I recall correctly are in the .060" diameter range. But I don't trust my memory LOL.... you can do a search here on this forum; it has been in several threads.
 
prochargedmopar said:
As you can tell I'm a rookie but next attempt I will be using a 9/32 bit or smaller to start the hole straight.
Then I will step up a size.
Take it slow, double and triple check.
I also bought a few grinding stones to smooth the surface at the hole entrance so I can have an easier time starting the drill.
Just gonna de-bur it a little.

I flat out was in a hurry and went straight to the 5/16" bit which is taking out a lot of meat all at once.
My bad.
Click to expand...
As Duane said very well, we started the hole straight into the bearing web surface to get a small 'divot' started not more than about .100" deep, and then with light pressure, slowly angled the drill to the correct angle to match the passage. And we stopped and looked every very short distance as we got each hole started, like every 1/8" of depth, to make sure the drill was following the hole. If it gets off early on, the process is toast and you aren't going to get it back on track.

We were successful with this technique with the 5/16" drill but you may well do better with the smaller drill first. Know that in some materials, a small hole size increase can be a problem as the drill will tend to grab and jump. Try this on the trashed block first; drill a 1" deep hole with the 9/32" drill and the try following on with the 5/16" drill to see how it behaves.

Pull out frequently to allow the chips to clear from the area near the drill's cutting edges; this will greatly lower the drilling pressure needed. And, IIRC we drilled pretty much dry for cast iron; I think we put in a few drop of kerosene or ATF to help keep the shaft of the drill rotating smoothly. And low drill speed! It has to be at least a few hundred RPM or so to prevent chattering and 'grabbing' in the iron so 400-500 seems to be good.

Hope it all works out 100%! We're all pullin' for ya!
 
prochargedmopar said:
As you can tell I'm a rookie but next attempt I will be using a 9/32 bit or smaller to start the hole straight.
Then I will step up a size.
Take it slow, double and triple check.
I also bought a few grinding stones to smooth the surface at the hole entrance so I can have an easier time starting the drill.
Just gonna de-bur it a little.

I flat out was in a hurry and went straight to the 5/16" bit which is taking out a lot of meat all at once.
My bad.
Click to expand...
.
On my magnum block I started with a 1/4 inch bit then went to a 9/32 then 5/16.
On my 340 the factory, step drilled it with a 5/16- 1/4. The last inch or two was all that needed drilled into the galley.
I did learn to stick a long screw driver or bar into the galley to stop me from drilling into the back wall of the galley.

procharged don't junk that block yet.

I used a battery powered drill at low speed and drilled it dry.
 
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An Mopardude318, if I may suggest this.... .put in the new HV pump first and don't change to the 90 degree adapter until a 2nd step, just to see the difference of the pump by itself.
 
Alex5280 said:
Wanted to say Thanks for posting the videos. I am doing most the the GJ oil mods now and seeing you drill bit "walk" and ruin the block is concerning. I had planned to drill the mains to the oil galley with a 9/32" bit....is there a way to keep it straight to avoid drilling offline??? Is it better to have a machine shop drill these??? Thanks Guys!
Click to expand...
As for the shop vs. at home, I guess it depends on your tools and experience.

The main thing for getting the drill to follow the existing passage is getting the hole started straight, and the tricky part is the fact that the oil passage does not go at a 90 degree angle to the web surface. We had success doing as described in the 1st paragraph of post #110.
 
nm9stheham said:
An Mopardude318, if I may suggest this.... .put in the new HV pump first and don't change to the 90 degree adapter until a 2nd step, just to see the difference of the pump by itself.
Click to expand...
it is the Napa 1068, shorter filter, not 6 inches long.
What I can do today, is put the 90* adapter on right now, with the same pump I have now, and take note and a video of the oil pressure at that location as well. then switch right back. I have everything, it'll take me no time.
 
Jadaharabi said:
.
On my magnum block I started with a 1/4 inch bit then went to a 9/32 then 5/16.
On my 340 the factory, step drilled it with a 5/16- 1/4. The last inch or two was all that needed drilled into the galley.
I did learn to stick a long screw driver or bar into the galley to stop me from drilling into the back wall of the galley.

procharged don't junk that block yet.

I used a battery powered drill at low speed and drilled it dry.
Click to expand...

I don’t plan to junk it.
It sat for 20yrs under my work bench.
Still contemplating a way to fill it and run dry block/wet heads in a drag situation.

Got lots of other projects to keep me busy while I ponder. lol

Along with lots of drilling/taping practice yet to do.
 
nm9stheham said:
We can't automatically make this conclusion on the pressure drop; you gotta account for the possibility that the 2 separate gauges are reading differently; the one at the 'line psi' location just may be off.

Some SMALL drop at the normal oil pressure sensor point ('line psi' in the data) with RPM is to be expected. Once the pressure relief spring starts limiting the pump outlet pressure, then the pressure at the top of the passages into the passenger side gallery is subject to the flow through the engine; that flow gradually increases with RPM, and will drop the pressures into the gallery a bit due to flow resistance in the filter and the passages to/from the filter. The 'line psi' difference 3k to 6k RPM is -2 psi; seems pretty good to me.

OP, what filter are you using?

From the data for 'oil psi', it is pretty obvious that you have the 50-ish psi relief spring with the present HV pump. So if the new pump is shimmed up to around 70 psi, then you ought to see a big change.

I 'took a look' yesterday at that site.. it did not say anything to help understand this.
Click to expand...
I agree with what you are saying but imho he should verify that he has 50 psi at 6,000 rpm and not 36. I think the line pressure reading dropping at higher rpm is indicative of an excessive leak.
The other reading stays steady at 49 psi regardless of rpm but the line pressure reading even with a bum gauge drops as the rpm goes up. That does not look right to me imho unless you have oil gushing out somewhere like lifters.
 
nm9stheham said:
That is odd... we had to drill 5/16" all the way from bearing web to gallery..... you never know.
Click to expand...

Just like the difference from the 74 block to 76’.
One has the valvetrain oil feed holes drilled to 1/4” and the other is over 5/16” all the way to cam.
 
Duane said:
I agree with what you are saying but imho he should verify that he has 50 psi at 6,000 rpm and not 36. I think the line pressure reading dropping at higher rpm is indicative of an excessive leak.
The other reading stays steady at 49 psi regardless of rpm but the line pressure reading even with a bum gauge drops as the rpm goes up. That does not look right to me imho unless you have oil gushing out somewhere like lifters.
Click to expand...
Just the model in my head....I definitely can see the flow increasing at the rods with RPM, as centrifugal force throws it out; it's like a negative pressure at the edges of the rod bearings. I can perhaps also see flow increasing out of the lifter area even if the clearances are snug. Either way, increased overall flow with the resulting few psi drop from 3k to 6k RPM would not surprise me at all even with everything being tight; operating conditions that effect oil flow are certainly changing with that much change in RPM.
 
So I put the 90* adapter on yesterday and hooked up the pressure gauge in the photo shown. (looks close to the header, it is not)

IMG-3974.jpg


That goes to the AutoMeter gauge in the Middle , and the AutoGauge on the left is back of the engine. I had my idle real low trying to get the lowest idle speed to capture the lowest pressure reading. (I had to blip the throttle to keep it from dying) For some odd reason, oil psi isn't going as low in idle like in the previous videos. Take note that the AutoGauge on the left reads consistently a little lower pressure on all my videos.

 
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mopardude318 said:
So I put the 90* adapter on yesterday and hooked up the pressure gauge in the photo shown. (looks close to the header, it is not)

View attachment 1715243371

That goes to the AutoMeter gauge in the Middle , and the AutoGauge on the left is back of the engine. I had my idle real low trying to get the lowest idle speed to capture the lowest pressure reading. (I had to blip the throttle to keep it from dying) For some odd reason, oil psi isn't going as low in idle like in the previous videos. Take note that the AutoGauge on the left reads consistently a little lower pressure on all my videos.

Click to expand...


I don't think anybody has mentioned it but is that little plug that's down there underneath the pressure sending unit approximately 7 and 1/2 in down or about 2 and 1/2 inch up from the bottom of the block missing. You know the one that doesn't affect oil pressure according to many experts.
 
Jadaharabi said:
I don't think anybody has mentioned it but is that little plug that's down there underneath the pressure sending unit approximately 7 and 1/2 in down or about 2 and 1/2 inch up from the bottom of the block missing. You know the one that doesn't affect oil pressure according to many experts.
Click to expand...

I'm pulling the motor today. How can I check that? Inserting a rod down that pressure take off port?
 
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