In block oiling or push rod oiling for 68' 430 top end?

I am cleaning up a 68' 430 runner to swap into a 67' Skylark and was thinking of stuffing a mild performance cam in. Something like a TA 284-88. I see early style lifters for the solid pushrods are hard to come by and expensive. (2 to 3 times the cost depending on where) Lifters for the the pushrod oiling are more readily available and much cheaper. I wanted to use the early rocker arms as they look to be in great shape too. I see I could do Hybrid push rods from TA but they are pricey at $200 as well. I am in Canada so adding the dollar conversion and shipping stuff gets really expensive fast from TA. I have a new set of late style lifters in my parts and have a couple sets of 455 pushrods I could use. I also have a couple sets of late 455 rocker arm sets I can use. It seems if trying to stick to a budget that converting to late style oiling makes the most sense. Any advice to share?
Greg

 

No problem converting. The holes in the block that oil the top end should be blocked. They are under the head on the deck about 3/8" in diameter.

 

I ran a ‘70 bottom end with ‘68 heads in my first GS. I used the ‘70 style lifters, pushrods, and gaskets, didn’t block any oil passages, just bolted it together and never had any oil trouble.
Patrick

 

Getting the oil passage tapped squarely is the hardest part of going pushrod oiling. Heck, even a monkey can do it.

 

I think your making the assumption that a stk length pushrod will work with cam. Maybe they will, maybe they won't?

Unfortunately no can tell till its assembled with the heads, cam, and lifters in place.

Oil through pushrods must be a better choice.....virtually every motor product from the 70s on that used pushrods oiled up the pushrod.

I vote to swap to that and get the right pushrods, odds are high that the stock ones won't fit and you will buying some anyways

 

I don't always tap the holes. A 3/8" drill, then a freeze plug with loctite on it. then cover over with silicone.Never a problem. Ben is right, chances are with a new cam the odds of the stock pushrods being the correct length are about the same as $2.00 gas.

 

Yes. I am aware that there is a fairly high chance I will need pushrods and will not know till after assembly. There is a chance they will work though. Again, hollow pushrods are more common and cheaper so that favours pushrod oiling. It sounds like there is no reason to want to use the earlier style rocker arms either. If is leave the cam that is in it I will use the original pieces. If I swap cams I will go push rod oiling.
Greg

 

The earlier rocker arms are stronger than the aluminum or stamped steel. So there is an advantage to them. Especially if the lift starts going over .500

 

Also the rocker ratio is a little more at 1.59.

 

How well do the early rocker arms oil through the pushrods when installing them on the 70' and later engines? I could save them and maybe use them on my 455 build I am doing. I could order a set of the TA hybrid pushrods with those rocker arms. I was planning on a more aggressive cam on that engine. I could even consider a solid lifter with those TA pushrods as they are adjustable.
Greg

 

I've heard of folks oiling the early rockers through the pushrods, but another downside is the rockers want to see a 3/8" ball on the pushrod rather than the later 5/16".

Maybe no big deal for low lift/spring pressure situations, but if you're thinking of running it pretty hard, I'd agree you're looking at hybrid pushrods again.

Devon

 

The TA Performance Hybrid push rods have the 3/8" ball upper for the old rockers with the 5/16" lowers for the new style lifters and are adjustable.

 

Some have had trouble w/adjustables, I haven't. Been using them for decades. First, the 5/16" stem (tube) dia on on the TA308S solid cam, now 3/8" stem on the TA294-04F solid cam, similar cam specs.

Devon

 

I been running TA 1406 lifters and oiling through the 68 rocker bars for nearly 10 years.

 

What are the chances of finding typical used rocker shafts and rocker arms that are good enough to reinstall?

My experience with other engine families is "about zero". I needed three full sets of Oldsmobile rocker arms and the stock aluminum pedestals to make one adequate set; and really, the aluminum pedestals should ALL be scrapped. The ball-pivot Chevy rockers may have useable balls and pivots, but the valve-tip ends are usually wiped-out. About the same for Pontiac, and the few Fords I've dicked with.

My three core Buick 455s really should have rocker shafts replaced (one's broken by previous owner/idiot during disassembly) because the under-side of each shaft is scored. Which means the rockers that match the scored areas of the shafts are scored. Which means that even without the wear at the valve-end of the rocker...they're junk.

God bless Melling's stronger/thicker rocker shafts, and the new rockers that go with them. (Unless, of course, you've got the Chevy-rocker Edelbrock heads. I haven't seen them in person; maybe there's a good reason--I always wondered why they used SBC rocker arms instead of designing them to accept BBC rockers. Perhaps there's not enough room under the valve cover for the 1.7 BBC rockers.)

 

I converted a 69 430 to pushrod oiling using the adjustable hybrid pushrod. Ta 310 camshaft. No issues at all. Stock 430 rockers.

 

I'm running 67 rockers and shafts on my 70 455 with pushrod oiling. no problems.

 

I highly recommend that you get a hybrid pushrod if your going to run the early rockers.. they will oil fine, they just oil "backward" from the original design. Instead of from the block, to the shaft, to the pushrod/shaft area, we turn that around, with oiling thru the pushrods. Works fine.

I tried to get away with using the 5/32 radius stock 455 pushrods with the big cups, about 25 years ago.. but they eventually damaged the tips.

I use 67-69 rockers extensively with mild roller cams, to keep customers from having to buy expensive roller rockers.. have about 6 motors out there with mild hyd rollers and those rockers, only had one failure.. all the cast aluminum rockers (67-72) have a steel insert where they contact the valve stem. Had one of those break.. TA does have the replacement pieces, typically.

It was suggested that we could use the 70-71 style with the mild rollers, but that proved to be not true.. the designed in side loading coupled with the fast ramp of the roller would break the nylon buttons every time.

I do use the 70-72 rockers on flat tappet engines, with HD rockers shafts from TA.

Good luck
JW

 

Thanks for your wisdom Jim. I have not decided for sure if we are going to swap the cam out on this 430 yet. If we do I will use up some late stamped steel rockers I have with hollow pushrods and late lifters. I think I will save the 430 rockers for my 455 build I am also doing. I could use those with hybrid push rods. It will allow me to consider a roller cam or solid lifter cam depending on how the build goes.
Greg