pushrods with or without oiling hole?

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70Hardtop

70Hardtop

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Every SB mopar engine i have seen has had solid pushrods. Well, what i mean is, solid ends fitted to hollow tubes (non-oiling). The oil, as we know is pumped up through the head to ingeniously pressurise the rocker shaft and feed the rockers and top end, with the pool of oil in the rocker arm running through that small hole to lube the rocker tip. But then i pulled apart a 1973 360 and found it had through holes in pushrods. As well, the lifters had solid discs, that is, no hole in the top of the lifter to let oil get to the pushrod anyway. I assume that engine had been rebuilt anyway, so whoever rebuilt it wasn't thinking of using these pushrods to get oil up to the rocker.

But the question is - if i use pushrods (talking ball/ball) with the oil hole and the lifters with the oil supply hole, won't this reduce oil pressure in the top end? I have noticed that most of the main brand names (Crower, Crane, Comp, Manley etc) make Mopar SB pushrods with oiling holes. But in a stock situation, with stock oilpump and stock rocker gear, will the hollow pushrods be ok to use, or have a detrimental effect on oil pressure up to the head?

thanks
 
No detrimental affect i can see. The oil is splashed/dribbled on the tips thru the hole in the rocker socket. The hollow pushrods are a little lighter too. I will always run hollow if I have a choice regardless of top end oiling.
 
look at the lifter and then guess where the oil gets in.

btw all/most push rods are hollow, you mean the feed through type.

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thanks for anwers, but you have misread the question. I wanted to know if i will get an oil pressure loss by using oiling pushrods and the oiling lifter, which is how AMC, Ford etc get their oil up there. If the stock Mopar pump has to pressurise the shafts up through the head AS WELL as pump oil up through each pushrod, i would assume that the stock oil pump would have to do a bigger job.
 
70Hardtop said:
If the stock Mopar pump has to pressurise the shafts up through the head AS WELL as pump oil up through each pushrod, i would assume that the stock oil pump would have to do a bigger job.
Click to expand...

I haven't tested it but it stands to reason that the oil pressure will be less with 16 more "oil leaks" per say.
 
I think I read the question right.. the answer is no. If you use the right lifter (which is what 1Wild is saying) the top end will have much more oil available because the stock system only oils the rockers when the holes in the cam connect the passages in the block, and only for a few degrees of rotation where "thru the lifters" oils 100% of the time. You should not see a drop in indicated pressure either.
 
thanks for replies...i'm starting to get an an idea of the answer. But i don't think the stock system has oil problems using the solid pushrods (Wild1, i know they are all tubular, solid p/rods have solid ends making them effectively solid to oil...i said this right at the first post.....) -the LA engines have a superior oil system compared to the other offerings from Detroit. Even with a few degrees of rotation allowing the holes in lifter and oil gallery to be lined up, this is sufficient to supply more than enough oil to the top end, with everything in tolerance as normal. If you use a priming rod into the oil pump on the end of a power drill through the distributor hole to prime your engine with the rocker covers off, you can clearly see the large quantities of oil getting pumped up through the shafts. I emailed Ryan Johnson at Shady Dell Speed Shop in Pennsylvania about this. All they do is A, LA and Magnum engines. So they have seen a few. He said he would not recommend using the AMC style lifter (oil hole in the top disc) with a stock pump. The original Chrysler hydraulic lifters had a solid top hat, so pushrods with or without oiling could be used. However most after market pushrods made by the big name brands are through-oiled probably because performance engines will be using a HV oil pump, as mandatory. In this case i wouldn't be concerned about an oil pressure loss up through the pushrods and the extra oil wouldn't hurt. i'm going with my gut feeling and using exactly what they used when it was designed by engineers. I also will email the Tech editor of Mopar Action, Rick Ehrenberg. I value his knowledge on (most) things engine-wise.

As for loss of lift.... (?) standard Hydraulic lifters have an inherent problem of too much pump-up at high rpm, making valve float more likely (valves stay open longer than they should) at higher rpm. Perhaps with a stock oilpump, that is not working as well as it should, and say, a slightly blocked oil pickup and using through-oiled pushrods and corresponding oiled lifters -yes - i could see a loss of lift. For sure
 
I have
1977 360 from a van. very low compression.
Block decked, its been like 20 years ago and i cant remember if it was .040 or .060 off the block (.060 i think) and I took .020 off the head. to get 9 1/2 or so compression. with a mild cam.

now
I had my heads reworked and I'm looking for push rods.
i can find almost any length push rod with oiling holes. solid tips are very limited. the answer in this thread. is not very clear. a while back I bought stock lifters from the auto parts store. they have the hole in the top of the lifter.

it sounds like i can use ether just want to make sure. if so i will check to see i loose any lift.
thanks
 
You won't notice much difference in oil pressure with the oiling type push rod verses solid end ( non oiling ) . I agree with one of the above posts that you should seek the lightest ( and strongest ) push rod . Once they are oil filled they are heavier than one without the oil hole because the cam is now lifting the weight of the oil . If you are building for street use it won't make that much difference but if you are building for a class you need every trick known. Use a GOOD , name brand synthetic oil and you won't have any lubrication problems . If you have had any head modifications performed i e .
milled , you should purchase a measuring push rod ( Comp - Cams ) and purchase the correct length for that engine & cam configuration .
Have fun with your build .
 
Do not be over concerned about pushrod weight.

This is because the pushrod is on the slow moving side of the valve train. The effective increase in weight between the two pushrods may be small but provides a huge increase in valve train stability. Remember the valve side of this valve train is the critical side where any weight savings will make marked improvements. No matter what we change, valve train stability is the goal.


http://www.mantonpushrods.com/Pushrod-Info.html
 
Oil hole lifters are just cheaper to make because they can cover 2 makers with one lifter (AMC style will work on Mopar) but cant if you make the top disk solid (No AMC compatability). Through oiling or solid plug ends is he question. I would use solid ends on any build short of a Magnum pedestal mount rocker.
 
I run hollow push rods in my stroker with oil coming up through lifters and oil coming up from heads to rocker shafts. I have run the engine with valve covers off. There is not an excessive amount of oil coming up to the rocker gear. Its not like its gushing out all over the place bleeding off pressure. Been running like this since 2008 no problems....
 
If you are running double valve springs with a high rate having pressure oiling to both ends of the pushed is good.
 
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