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

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Have any of you seen or done this on a mopar? These are from high hp LS engines at a buddies shop. There is also a groove in the block going from the main oil hole going up to this second hole in the bearing.

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Never done on a Mopar but yes that is standard Ls oiling method. Gm theory to feed a second supply on the major thrust side of the bearings. To me full groove does the same thing
Unless you believe that the extra bearing surface is required.
 
I think Yellow Rose posted pictures of this mod on one of the oiling system threads.
I posted pics from a show where they were adding that oil groove to older chev block under the bearing shells.
They used an old grooved bearing she'll as a fixture and a die grinder to add the groove to the block and drilled extra oil holes in the bearings.
 
Full groove seems to do the trick right well.
 
Agre
FWIW, for a data point on the chamfers leaking: My son's 340 was a virgin block, with the chamfers, and the lifter bores were unworn. (A couple were so tight that we had to get Crane to send us a few extra HFT lifters with OD on the small end of the range, so we could fit them in some of those tight lifter bores.)

Fired it up with the drill to pre-oil and check oil to the rockers (since I had added some rocker oiling holes), and did not see any real oil flowing/oozing out of the chamfered bores at all. So, from that, I wold suspect excess oiling there simply has to do with bore wear. (Test conditions: Oil was 1W30 at room temp, with a drill at 600 RPM, which corresponds to 1200 engine RPM. Pressure was a bit over 70 psi at the usual pressure sensor location.)
Agreed but most rebuilds are on a block with significant mileage and the lifter bores would have some wear.
 
Pictures gone in post #3.
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Have you or are you going to try this?
I don't think I will be. I've done all of the guitar Jones mods, tubed the block, and gave it full time rocker oiling. All of that is probably way overkill for my build anyway. I just thought it was interesting and thought I'd get some opinions on it here.
 
I've grooved the block saddle from the oil feed to the parting line then side fed the mains where the additional area at the cap/ block split is
 
I've grooved the block saddle from the oil feed to the parting line then side fed the mains where the additional area at the cap/ block split is
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How did that work out for tou?
Did you use a sealer inbetween the block and cap? Studs or bolts?
 
I can say without even blinking that a crossover tube is worthless. It does zero. Except put extra holes in the block. That "fix" was never a fix and should be forgotten about.

The oiling system is a simple hydraulic system. All that bullshit about the oil moving too fast to turn down the feed is just that...bullshit. Or a lie.

Any engine running solid lifters of ANY kind should be tubed or bushed. If you want to run pushrod oiling, then drill a .0625 hole in the bushings or tube where it passes through the lifter bore and run it.

If you have your **** together, 7500 RPM with a QUALITY oil pan, a HV pump with no less than 80 PSI at WOT and full groove mains is doable. Any more RPM than that and it get iffy. Over 8000 and you need to correct the oil timing.

The crossover is just doing work to make someone feel better. Doesn't do a thing.
 
jad
no sealers under the bearing shell or cap parting line-
the top of the bearing where the oil hole is is where the most clearance and leakage is but you do need to feed the rods so you have to run a half grove or 3/4 grove
bearings
The popular oil feed diagram is for inline engines and shows best place to feed is somewhere around 4 oclock now with a V8 you have, in theory, two locations, one for the loads from each bank. HOWEVER IMHO the perfect spots moves around in a running engine hence from the side as it's an easy mod and in theory feeds the hydrodynamic wedge on the lower shell
 

Jad I can tell you the fool who wrote the page you have posted here is full of **** and HE doesn't understand how the oiling system works. I've already explained (and done it many times with my own engines and used to have the junk parts to prove that author is stupid or lying) how you correct the oil timing to make a Chrysler oil at high RPM. The tube does nothing.

Look at a SBC and compare that to a SBM. They are essentially the exact same EXCEPT in one area. The oil feed holes in the crank are exactly the same. The difference is the location of the oil hole in the main bearing bulk head. And a SBC will oil way past 10k. And that's before priority oiling came along.

I just hate to see guys wasting time and money on junk that doesn't nothing. Piss on Chrysler for not correcting this decades ago.
 
He is an engineer that has worked for Chrysler and wrote the book on how to make a small block live.
He showed Carl my old boss how to do it and modified his block for him that was run in it the old John Force funny car that he owned in B Econo funny.
There are people that have done the crossover on circle track motors and drag race motors and boat motors and street motors that think differently.
If you have a better way to make a sbm live at high rpm show me some proof.
 
He is an engineer that has worked for Chrysler and wrote the book on how to make a small block live.
He showed Carl my old boss how to do it and modified his block for him that was run in it the old John Force funny car that he owned in B Econo funny.
There are people that have done the crossover on circle track motors and drag race motors and boat motors and street motors that think differently.
If you have a better way to make a sbm live at high rpm show me some proof.


Want me to make a video?? I can. If you want to see why the Chrysler doesn't oil, look at the Chevy. And find the difference.

I don't care who wrote the book. He is wrong. I'd tell him to his face. Junk **** mods like that casused me to kick a bunch of rods out of very expensive blocks. So I have done it. I have fixed it. I have explained it right here, more than once.

You ain't fixing **** with that crossover tube. We need to STOP passing bad info around like herpes. If you personally know that author, PM me and we can conference call him and I'll explain to him why he's wrong.


Edit: I most likely have the book. Several months back this was a topic and I didn't have the particular book that IIRC Duane was using so I bought the book to see for myself. It's pretty evident that NONE of these people ever made power over 8000 RPM's or they'd fix what they write. And no, a dry sump doesn't fix it either.
 
Would love to see your video. Or pictures.

Show me a better way if you can. Your the only person I've seen that has bad mouthed this mod. If there were 10 people that said it was a bad mod I might change my thinking.

To add to my thought 10 people would probably not change my mind because I know it works.
 
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Would love to see your video. Or pictures.

Show me a better way if you can. Your the only person I've seen that has bad mouthed this mod. If there were 10 people that said it was a bad mod I might change my thinking.


Never put your faith in numbers. Just because many say it, doesn't make it right.

I just found out its date night. Who knew. I didn't. But I'm told it is.

If I get a chance tomorrow I'll pull out a block and a crank. Wish I had a SBC sitting here. It's much easier and quicker to do a video to explain how you fix it. For 7500 and under all you need is the right pan, full groove mains and the lifter leaks blocked. Once you go past that, you need to fix Walter P. Chrysler's poorly copied Buick/Pontiac oiling system. I forget which GM brand he started with, IIRC it's Buick but both the buick and Pontiac have the same jacked up oil timing. It's hard to fault the engineers back then. They didn't know dumb *** racers were going to take 1950's architecture and spin the guts out of it. I mean, think about it. Even in the 1970's unless you were running Pro Stock or Modified eliminator most guys weren't going much past 7500. And even at that, they were not quite at the 2 HP/CID mark. Today, Pro Stock is banging on 3 HP/CID naturally aspirated. In 1970 you'd have been locked in a rubber room for even think that possible.

Off to the shower and then date night. Unreal. Some day, I'll be my own boss. Maybe. If the wife lets me.
 
We know Oldsmobile's problem starts with the weak block webbing causing block flex. But the supposed cure is to run looser main bearing clearances.
What I'm saying is everybody has their problems and there are more that one way to skin a cat.
The crossover tube is one of the ways to save the bottom end on a hydraulic cammed sbm. It has been proven time and time agin.
I am interested in the crank timeing groove that was mentioned earlier. Also would like to see the video.
 
To yellow rose, have learned about 70 degree timed oiling from your previous posts and would like to see your diagrams or video, want to know about bearing saddle grooving/drilling or crank drilling to accomplish this. My son's engine will be over 7500 through traps.
 
We know Oldsmobile's problem starts with the weak block webbing causing block flex. But the supposed cure is to run looser main bearing clearances.
What I'm saying is everybody has their problems and there are more that one way to skin a cat.
The crossover tube is one of the ways to save the bottom end on a hydraulic cammed sbm. It has been proven time and time agin.
I am interested in the crank timeing groove that was mentioned earlier. Also would like to see the video.
My original thought when I saw the ls mains and main bearings grooved like this was that maybe this was a poor man's fix for the oil timing issue. Idk
 
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