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I'm getting close to switching to a roller cam in the big block!

Generally speaking , the threads at the bottom are what they're talking about. I imagine they might be OK, from the looks of one picture it seems the oil hole will oil the cup. But that's one of the concerns.

At TDC through the dist hole you can see the lobes are up a bit. Or if 180 out, the lobes will be pointing down.
 
As I looked down the distributor hole to watch the intake lobe, I noticed this…

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The lobe looks close to the axle of the nearby lifter. I did not notice this when the intake was off where I had a clearer view.

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I’ve rotated the engine several times. If they were going o make contact, they would have already.

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I’m about two hours from first fire.

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All the front accessories are on and the belts are snug. The rerouted radiator overflow jug and line will work. I shortened the overflow hose after this shot was taken. It now runs right up the side and over the top nicely.
I thought about the close proximity of the lifter body and the nearby cam lobe. The pictures make them look closer than they really are.
Here is a shot of the lifters for cylinder 1 through the lifter valley.

RC 448E.JPG


For clarification...

RC 448F.JPG


It is #2 Exhaust lobe that is close to #1 Intake here:

RC 448B.JPG


Looking at the taper of the lifters....

RC 448C.jpeg


RC 448D.JPG


The edges of the lobe are above the taper. This is one instance where limiting camshaft end play really makes sense. The cam would have to go rearward maybe .100 or so for the #2 lobe to touch the lifter and since the cam sprocket has a Torrington bearing in it, the cam can't really move rearward much. Looking over the pictures I took, this is the only place where the lifter and lobe are this close. It worried me at first but it just looks closer than it really is.
This is probably a matter of very close tolerances that are well within the safety margin.
 
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Just for the sake of curiosity, I looked at the lobe spacing on this cam and another one.

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Closer...

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It looks like even the flat tappet cams have the #1 Intake and the #3 exhaust lobes close together.

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Above, look how far the lifter hangs off the lobe!
 
In a flat tappet application only half the lifter rides on the cam, that's part of what causes it to rotate..

My understanding is that the offset is part of it. I was just surprised at how much offset that there was. This would seem to pose a challenge to developing a roller lifter for this engine since you'd be limited to a narrower wheel so the edge doesn't hang off the lobe.
There are things like this that go unnoticed by me but when I stumble upon them, it makes me curious.
Looking at the Lunati cam, a picture taken at least 3 1/2 years ago.....

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In addition to cylinders 1 and 2, cylinders 3 and 4 have lobes close together, as do cylinders 7 and 8. Note that 3 and 4 have nearby lobes that almost oppose while 1 and 2 and 7 and 8 have lobes that are closer to peak lift. I know why, I just was surprised to notice this now.
This means nothing as long as everything clears and there is no interference, I just found it to be interesting.
 
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Oooops...THAT is the Lunati that I've had for years!
 
First fire!

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That can mean a few things, most of them bad.
That isn’t the case today. I did have the water hose nearby along with the fire extinguishers.

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Man, the whole area got crowded over the past few days. All this stuff to make the car comfortable to drive on trips.
For the FOURTH time in a row, a fresh build started up within 5 seconds. Of the last four, two were with used flat tappet camshafts with matching lifters and the other two were roller camshafts. Of ALL situations where one can afford to crank and crank a bit to start it up without worry of cam and lifter failure and four start right up. What a mixed blessing. I’m glad it started up though. I have a valve cover leak on the 1357 side, I have major oil smoke coming off the header. It idles smooth though. Only a fraction of the valve train noise the solid lifter cam had. No coolant leaks. Minor belt squeal. I need to get some longer bolts for these valve covers. The thicker gaskets ate up the length of these ARP ones. Oil pressure shot right up as soon as it started. Water temp climbed as normal. I didn’t run it too long. It was starting to look like Cheech and Chong were hanging out in the shop.

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I feel good. Nothing caught fire and so far, the parts are staying on the inside.
 
I'm using those FP gaskets, along with the MP covers, on the wagon. I RTV'd the gaskets to the covers for a day before putting them on. Oil came out of the bottom fasteners. I'm thinking there is enough of a ledge on the backside for oil to get out through the bolt holes in certain areas. If I use those covers again, I'll pack the backsides around the bolt holes to alleviate the leaks.
 
I'm using those FP gaskets, along with the MP covers, on the wagon. I RTV'd the gaskets to the covers for a day before putting them on. Oil came out of the bottom fasteners. I'm thinking there is enough of a ledge on the backside for oil to get out through the bolt holes in certain areas. If I use those covers again, I'll pack the backsides around the bolt holes to alleviate the leaks.

Looking at the valve cover, it does not look like oil made it past the rail. It did look wet around the holes. One of the bolt holes in the heads started to strip out due to these bolts being so short. Because of that, I need to use longer fasteners to get adequate clamping force. I wonder how much oil may have dripped out of the heads during pre-oiling. There was a puddle of oil below the right header after adjusting the valves. Maybe some pooled at the top of the collector? Maybe I'll get the valve cover back on and then put the car up on the lift to see if oil stains show up on the headers.
I'm going to use studs all along the bottom row and see if clamping it down more will help. If it doesn't, I have another gasket to try.
The timing has not been set. I just stabbed the distributor and tightened it, then left it alone. Talk about good luck!
Before I started it up, I added 4 gallons of fresh 91 octane fuel and then filled the primary bowl of the carburetor. The radiator was filled, the A/C hoses were tightened, the heater hose clamps secured. This was easily the least dramatic start up that I have ever had.
 
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Looking again, the valve cover leak could be right here at the lower rear corner...

RC 453.JPG


Okay, before anyone asks, this....

RC 454 Z.JPG


Is a guard that I made many years ago to block oil splash from getting sucked up by the PCV valve. I had an oil burning problem and thought I was sucking oil at the PCV.
Back on point...
Closer look at the gasket...

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It is wet around the lower rear hole, forward of that a bit and forward of the next hole.

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The wetness here could be just oil dripping from the rail but I am not sure.

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The lower front section seems okay. Now that I cleaned it.....

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With a hydraulic cam, I could probably use RTV on the exposed side of the gasket here to then seal directly against the head.

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The last 2 cams I used were solid lifter and even though the lash didn't loosen up over time, I wanted to be able to pull the valve covers easier for any service.

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With a hydraulic setup now, I could seal this dude up tight. If I need to pull the valve covers off later, I'll just consider valve cover gaskets a cost of doing business.
 
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