CMcAllister
Well-Known Member
Title says "My take on the oiling system crossover tube for the small block". I'm assuming high RPM small blocks. That's my take on the subject.
My take on the oiling system crossover tube for the small block
- Thread starter Jadaharabi
- Start date
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I think he’s got that.....
AKA = Drivers side
According to the Chrysler engineer that designed this and implemented it, the crossover is to be used only for high reving sb's with hydraulic lifters.
high rev with hydraulic lifters ? what are the rpm parameters, I would think the stock system would support 6500 with the right valve spring, lifter and oil capacity.
CMcAllister
Well-Known Member
high rev with hydraulic lifters ? what are the rpm parameters, I would think the stock system would support 6500 with the right valve spring, lifter and oil capacity.
7200 and up. Never used a hydraulic in anything like that. Always solid rollers. Any mods I've ever done (or not) were for the purpose of keeping oil on the crank at high RPMs to avoid starving the bearings. That is the priority.
I agree, for me anything above 6500 gets a solid. I spin low deck big blocks 7500 with solid flat tappets, but mostly 6800.
The words and pictures of Larry Atherton.
Forgot one.
CMcAllister
Well-Known Member
Why would I put oil in the left galley when I run a solid cam, bush the lifter bores and run a -6 feed line from the rear of the block to the very front of the right galley, effectively feeding it from both ends to correct the effects of oil having to run the gauntlet from the rear to the front of the block? Call it a crossover, I'm just feeding the front of the right galley, keeping ALL the oil in the side that matters, rather than taking any detours.
That is not a crossover when you are feeding the same side. You are not using hydraulic lifters anyway so you would block the left side.
Why are you double feeding the right side?
In the MoPar engines book, they say 5500 rpm’s for regular cars. I read somewhere, IIRC, HP pumps were suggested for up to 6200/6300 rpm. No other modifications were mentioned as I remember it. The conservative rpm ceiling was due to irregular or non standardized machining of the oil feed holes throughout the block.high rev with hydraulic lifters ? what are the rpm parameters, I would think the stock system would support 6500 with the right valve spring, lifter and oil capacity.
Some engines I have had in the past have had the oil passages drilled larger than others. Why this is I do not know. But these have served me well to 6500.
In all honesty, making power last this level requires a larger than normal cam one would find being used regularly in the street and it would more than likely be used with very well ported heads. Yes I’m guilty of the not normal crowd! LMAO!!!
Below are solid cam builds. Hydraulic cams normally fall off after 6500 if they go that high.
An excellent engine build AND (shown) dyno sheet of this can be found in threads by @RAMM here where he has a solid lifter cam duration of [email protected]. Peak HP is 6700 and only 2 hp difference than at 6500.
371 build W/Big Mouth heads
A little higher max rpm and some serious parts here; 360 Street/Strip Bruiser-Dyno results
The cross over tube makes sense for Hydraulic cams. Solid cams, not so much.
Wyrmrider
Well-Known Member
Jad
lighten up
CMcAllister gets it and made the exception for hyd lifters in his post previous page
comprende?
the reason to feed from the front and back is that the lifters block the right oil galley
The dumbbell ones are just that- they churn up the oil
and the good solid body ones block the passage
(which is why the passage is drilled when using them even when feeding from the front)
I have a long stepped reamer for doing just this- the pilot makes it go straight -
lighten up
CMcAllister gets it and made the exception for hyd lifters in his post previous page
comprende?
the reason to feed from the front and back is that the lifters block the right oil galley
The dumbbell ones are just that- they churn up the oil
and the good solid body ones block the passage
(which is why the passage is drilled when using them even when feeding from the front)
I have a long stepped reamer for doing just this- the pilot makes it go straight -
nm9stheham
Well-Known Member
Seems obvious... to reduce the oil velocity in the back portion of the right side gallery and solve that particular issue.
There’s an issue?
CMcAllister
Well-Known Member
Couple of reasons. 1) I'm not a hydrodynamics expert, but I try to understand what's going on. Stock set-up is putting oil into one end of the galley. There are 4 holes being fed along the way, hopefully maintaining equal and adequate pressure and volume at the bottom of the hole (main journal). There are 8 restrictions along the way (lifters or bushings). Putting oil into both ends of the passage should reduce the oil flowing through so the oil doesn't "run past" any feed passages and equalize pressure and available volume in the galley. And available oil only has to go by four lifter restrictions at most. 2) It gives me a place to pick up oil for other places rather than bleeding it off of the mains.
As long as the oil pressure level is high enough for the intended rpm to be spun, there should be zero oil feeding issues. Be it the first or last oil passage.
Oil pressure should read the same pressure at the front or back of the main feed galley.
Oil pressure should read the same pressure at the front or back of the main feed galley.
Wyrmrider
Well-Known Member
should but it doesn't
problem is where oil goes from left to right and trying to feed a main at the same time
put a really good pressure gauge at the left rear, left front, right front
I've heard that it's been done but not by me but roundy round builder went to front oiling
problem is where oil goes from left to right and trying to feed a main at the same time
put a really good pressure gauge at the left rear, left front, right front
I've heard that it's been done but not by me but roundy round builder went to front oiling
Is this post still going. Man those hydraulic cam engines must be some real runners. Maybe I should throw this 5.10 lift purple shaft in instead of selling it. Lol
CMcAllister
Well-Known Member
Zero lash and Ti valves. It'll rev.
Well, be it as it may, I never had a problem at 6500. Do these roundy guys exceed that with hyd. cams?
replicaracer43
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I have on occasion, we went to a track we had never been to, had a bit too much rear gear, and ran about 100 laps one night, tach recall said 7200 after the feature.
WOW! Woo-Wee! That’s a lotta rpm over and over again. What was the cams duration of you remember? Not a street grind I’d imagine! LOL
replicaracer43
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No, definitely not a street grind! It was a lift rule limited cam, I think .420 if I remember correctly, and duration was high 240s @.050, sorta like a super stock "cheater" cam. Extreamly fast ramps, and was pretty hard on valve springs, but it did make power. Not at 7200 though!
Duane
Well-Known Member
I also never disagreed with you on the oil timing issue.
I only disagreed on how you fixed it.
The key thing that I think people miss is that regardless of whether you choose to tube or bush the block or run the crossover line,
Both methods require you to plug the end of the galley on the passenger side.
Jadas discussion on this thread is about the crossover method to deal with the galley problem.
Even tubing or bushing the block is dealing with the galley issue.
Yellow rose you are talking about what goes on after the oil leaves the galley and how it gets to the bearings.
IMHO those are two different issues.
Regardless of which method you choose, the common issue is the blocking of the end of the galley which cuts the leakage completely from the drivers side and #1 main and rod no longer have the entire drivers side rocker and lifter oiling being taken off of number #1 main which is also starving the rods fed from that main.
When you cut that leakage you also eliminate the velocity.
The oil is mostly pressurizing instead of flowing to all those leaks.
The oil timing as I have said is a different problem requiring a different fix.
Even in that book explaining the crossover tube the author acknowledges that there were two approved methods to deal with the velocity issue. They acknowledge the Accepted Chrysler approved method of tubing or bushing the block. Both methods require a plug at the end of the galley.
Bob Mullen who helped design the crossover was an engineer, a member of the society of automotive engineers and the inventor of the w2 head. He has great credentials that I would not so quickly dismiss.
I also agree with Pittsburgh racer that with today's stroker motors being so common the big rpm is not required anymore. Torque is where it's at.
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