Well I am still working on the 95 LT1 That has no oil to the rocker arms. I have done some investigations and all the galley plugs are installed and after using a manual gauge found it has 55psi plus with a drill turing 600 rpms (1200 engine). So it has plenty of oil pressure so why no oil to the rockers? I know now it has to be a lifter, camshaft, pushrod, or/and rocker problem. The cam is a comp hyd roller with a reduced base circle, the lifters are stock gm roller lifters (origional), stock hardened push rods and crane gold 1.6 rockers. Could the reduced base circle be causing he problem? I mean it has basicly no oil to the rockers. This is after 15-20min of running and another 20 min post disassembly lubing with drill. I did prelube it and some oil came out the rocker but it took a LONG time and it was very little, thought is was just my dieing drill. Anyone?

cam bearings installed wrong maybe ??

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1972 chevy camaro ss 350 sbc 425 hp/356 @ the wheels,350 trans,373 gears,daily driver with restification in progress for the old school / day 2 look
future plans- turning it into a baldwin motion Z30 clone

"IF IT'S TO LOUD YOUR TO OLD"
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A reduced base circle cam can change the oil timing because it moves the groove in the outer diameter of the lifter lower in the bore.
If it moves it below the level of the oil gallery for most of it's travel, it will only oil at max lift, or none at all.
You need to move a valve to max lift, pre-lube, and see if it oils.
Then progressively move it downward and see when it stops oiling.
One problem is...
A hydraulic lifter may not oil when the plunger is compressed. You may have to adjsut the lash on the rocker at full lift to see what is happening there too...

I will have to look at the block and see for sure but on factory roller the inlet oil hole is higher on the side. I will look for sure and see if that is possible. I am out of ideas so any suggestions are great. I am 99% sure that the problem is either the lifters or the cam to lifter relationship causing the oil not to get into the lifter. If I pull out a lifter there is plenty of oil running into the block.

Not sure why you have 2 posts going on the same problem but here is what I posted in your other one:

<font face="Arial,Verdana" size="2">I had this exact same problem with my small block and i'll bet ya you got the same problem. When the machinist installed the rear cam bearing he didn't push it all the way back in the bore and it left the oil groove exposed. I had great oil pressure but no oil to the top end. By having the groove exposed it would not pass oil down through to the lifters and up the pushrods.</font>

<font face="Arial,Verdana" size="2">Originally posted by N-Memory:
Not sure why you have 2 posts going on the same problem but here is what I posted in your other one:

I had this exact same problem with my small block and i'll bet ya you got the same problem. When the machinist installed the rear cam bearing he didn't push it all the way back in the bore and it left the oil groove exposed. I had great oil pressure but no oil to the top end. By having the groove exposed it would not pass oil down through to the lifters and up the pushrods.</font>

Agree

It has oil to the topend if I pull one of the lifters oil runs down the bore into the block. The lifters all have oil in them but it is not going to the rockers. I don't know if it is cause they aren't building pressure enough to push up the push rod or if the lifter is blocking the oil some how? Or the rocker is not letting the oil out because of some geometery problem I have (looks very close and is just a little off).

I screwed up and posted it twice accedently Sorry.

Canya pull the pushrods and squirt carb cleaner clean thru them and retry it w/o any lube on them ?

Ya but went I say I put a dab on the push rods I mean just a small dot, most of it is gone now. I have look through the pushrods to see if I missed cleaning them or something. Most if not all the prelube is now gone because of taking things apart multiple times. I guess I am looking for a epiphany on this one. I am not a newby on engines (esp sbc) by far but this one is kicking my ass. I have seen things in disassembly that should have never worked and did. I have gone over and over this and I can't find a thing wrong. I guess I will just have to start swapping out parts and seeing which ones make a difference, then compare the two parts. The problem is I don't have anymore stock hyd roller lifters to try. I may try some stock hyd flat tappets and not turn the engine over just put them in adjust the preload and use a drill to build the pressure and see if it works. I am never building something for someone else ever again, I alway seem to find trouble when doing it for someone else.

Just cause there's oil in the lifter bores doesnt' mean there is enough pressure and volume to push it up the pushrods. I still think your rear cam bearing is not installed correctly.

I pulled the intake and put my finger down the dist hole. If it isn't correct it is wrong by less that a 1/16 most likely less.

I had a similar problem before, can you try it w/1,5 rockers? if it corrects the problem, you have 2 chances, 1- go on w/ 1,5 rockers, 2- remove the heads and deburr the pushrod holes carefully.( w/1,6 rockers at full lift pushrod touches the pushrod slot on the head- geometry problem).

yesterday I went and bought 1 new roller lifter from the parts store. It has oil to the rockers in all locations. So great just buy 15 others right, but what could I have messed up in the reassembly of 16 lifters? Today I am going to take a new one and old one apart and compare them. Blows my mind that lifters that worked for 126K could suddenly stop working.

So its all good now ?

That's damn funny....at least you figured it out. Sorta 'cheap' cure....other than all the hassles prior....

Not many parts inside a lifter. Glad you figured it out though!

Well I worked on it more today. Have to wait till monday to order the other lifters. Took one old one apart and the new one. Parts are slightly different in design but not enough to cause the problem (old ones assembled correctly). So I did more diagnostics. The new lifter will put out good oil on all locations I tried, but I also got one other lifter to bleed just as good. Tried to see why it was bleeding now but not earlier. I found I didn't readjust the lash on the lifter. So I tightened it up 3/4 of a turn and the oil stopped, but the new lifter was adjusted right and kept bleeding. So the question is, is it really the lifter cup and the pushrod tip that are the difference? The lifters only real difference is that the cup on old lifters are worn and the new one isn't. So is it just that the lifters and pushrods have worn together and now with a decked block and reduced circle cam the geometry is off just enough to cause problems now? That is about the only thing it could be. But now should we buy slightly shorter pushrods and see if it works, or just buy new lifters even thought it may just be a bandaid? The Geometery isn't perfect but pretty close. Still kinda stumped. Now the other new problem is I had the guy who owns the car pull the timing chain and cover and in the process he broke the drive pin on the cam. I wasn't worried till today when I found it must be made of diamonds. Killed 4 drill bits and just a dent. So now what is the hardest drill bit I can buy in a 3/32? We were looking into carbide with a stright flute from mcmaster Carr but I don't know if even that will do it. Man I want this project done and out of my hair. At least till we have to figure out the LT1 edit.

80'427-You are correct, it might as well be made out of diamond. They use hardened dowel pins, which are well into the 50's on the Rc scale. Even with carbide you need a lot of pressure to cut it, IF you're lucky. Do you have any machine shop friends that run EDM machines? That is the best way to get it out.

Nobody has a edm machine in our area or nebraska. I guess we will have to pull out the camshaft( was doing it in the car with a short air drill and a guide). The factory one was soft mared it a little when pulling it out of the old cam shaft. Well I may be able to pull the cam shaft throught the front of the car like I have done in the past, not sure if it car be done on a 4 gen. Just one more stumbing block.

In the 4th gen cams I've handled the dowel pin hole goes straight thru. Just pull it and punch/drift it thru.

If not....hmmm....you might wanna try drilling the back of the cam lobe behind the pin and try pushing it out like that.