head oil suppy ?.

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abodyhotrod

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so i have done an oil mod installing a tube in my passenger lifter oil gally as well drilled all holes needed to suppy mains and blocked from number 1 main to driver lifter oil gally.

the question is this leaves one head supplied by a main oil gally and the driver side only supplied by the cam. the cam seems to restrict oil. have any heard of heads needing more oil with this oil kit? should i just tap the two together? but will i lose pressure just dumping oil in the heads? or do i just restrict the pass side?


i left alot out but the more oil falling on the solid lifters will probly help them last longer. since the oil kit stops the oil to the lifters. its a high lift pressure thing.
 
I guess you need to explain why you did this modification in the first place and little more about the engine itself before I for one would be prepared to say anything, JMO.

Terry
 
mopar performance used to make a kit for high lift cams that would expose the bottom of the oil gally in the lifter bore during max lift. comp cams recommends this kit with solid lifters and cam they gave me. not only is it a high lift thing the clearance of the solid lifters will just dump oil out and not hold sufficient pressure. this is why i have this now problem knowing all the oil passeges and where it goes lead to the ?"s i have asked what should i do about the differance in oil pressure to heads.
 
well...should have asked around before doing this mod...you must have gotten a chevy guy at comp cams....

it was mostly used because of the old roller lifter would expose the oil galleries...never heard of that problem with solids lifters...since they are solid..

new roller lifters are now solid bodies and do not need the oil gallery modifications ....even comp cam sells these roller lifters...

only benefits you have now...is that if a lifter comes out of the bore you do not lose oil pressure...

it has been years since i last read that oil modifications....someone will come along and help ya....kind of late tonight...
 
The oil for the heads comes from the main bearing feed below the camshaft bore. Oil flows out of the pump into the right side lifter galley, then down the feed passages to the mains, then up from the #2 and #4 mains to the #2 and #4 cam bearing bores, then thru a hole in the cam, then up the passages to the rocker stand. The tubing mod does nothing to change this. It does save oil pressure (and volume) loss from worn lifter bores in the left side lifter galley, and was done more in endurance and high rpm engines, regardles of cam type. For really bad lifter bores, both lifter galleys can be tubed but you must also re-drill the feeds to the main bearings on the right lifter galley. The "cross over" tube mod is for the #4 main starvation issues caused by high rpms and larger bearing clearances to slow down the speed of the oil down the right side lifter gallery.
 
your just about right but the oil to the head on the left gets a direct flow of oil from the left lifter oil gally and the right only gets it from the cam.

these two little oil galleys that come to the deck of the block intersect thru the lifter galleys before it reaches the cam. the right side oil has been stopped by tapping the 1st main oil gally to the right side.
now no oil goes into the right lifter gally, and i cant supply the right head with the same amount of oil as the left. only thru the cam
i thought someone has reconized this problem or may have done this before but i guess not.

gonna tap the two together/ ive see tapping the two lifter galleys together.

good luck to me abodyhotrod
 
abodyhotrod said:
your just about right but the oil to the head on the left gets a direct flow of oil from the left lifter oil gally and the right only gets it from the cam.

these two little oil galleys that come to the deck of the block intersect thru the lifter galleys before it reaches the cam. the right side oil has been stopped by tapping the 1st main oil gally to the right side.
now no oil goes into the right lifter gally, and i cant supply the right head with the same amount of oil as the left. only thru the cam
i thought someone has reconized this problem or may have done this before but i guess not.

gonna tap the two together/ ive see tapping the two lifter galleys together.

good luck to me abodyhotrod
Click to expand...


you're sure of that? If that were the case, the left rockers would oil during prelubing.. They dont. You have to rotate the cam to get them to oil... You can groove the cam journals to get 100% top end oiling if you want, but you have to restrict the flow with a restrictor at the deck surface. Now you've got me curious...lol. I'll have to hit the garage to see...
 
I believe both heads oil up through the cam bearing on a stock LA small block. I remember looking at the holes in my cam and checking those two cam bearings for holes.
 
you are trying to supply oil to the heads with a 98 magnum block?

is that correct?
 
tried to take sum pictures, you can really only see the straw in the last pic.
whats so confusing its a hybrid meaning mag block with LA heads. the hole on the deck was only tapped through to the gally that was already there.

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Now I see. Its not an LA block. Someone drilled that hole for shaft mount oiling to the heads.
 
mr mopar, do you think if the two were tapped together so they have the same pressure i should restrict the amount of oil to the head it has deep pan and high volume pump?
 
Eureka... that's why. Not an LA...lol I would restrict it, yes. You can eitehr take a grub screw and drill a hole in it (I'd use .060" hole), then tap and run the screw below the deck... or drill it with larger step at the deck and use a holley carb jet to "tune" the oil flow. Factory LA systems only oil the head/rockers for the 20-30° that the camshaft connects the galley up from the mains and the ones up to the heads. The HV pump might not have any pressure or volume issues, but it will pump a TON of oil up there because it's a 100% pressure fed now. Just as a "for isntance... the hole that straw is in looks like 80% of a main bearing feed passage... That's a lot of oil...
 
so thanks alot guys who helped i know this isnt a regular rebuild and being a mag block its different to most but i will check into the angle at witch it was drilled as to i am curuies about that head oil passage.... i heard thats all i had to do to the block to adapt the two.
i do know when at the machine shop we stuck a wire up from the cam bearing and it went half way up the gally to the deck before we drilled through the deck. hmmm no worries i will fix the problem.
thanks again to who helped as my 550+ hp 408 is on the way.....i just want to go fast like sum of us. you live and learn...
 
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