Camshaft oil timing to shafts

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4spdragtop

4spdragtop

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OK, I'm a little stumped on this. Cam is degreed, adjustable rockers installed, thanks @CFD244 Troy for spacers but also for pushrod info lol. Lash is set .022. Solid flat tappet. When priming for oil with engine on stand, I have oil flow up to rockers, but not at the crank timing degrees that I have read.
From what I've read oil should flow at 90* BEFORE TDC compression #1 cyl for Pass side and 20* AFTER TDC EXHAUST #1 for drivers side.
If I'm doing this correct I am getting good flow, BUT
Pass side is 118* BTDC Compression
Drivers is 320* ATDC Compression, which is same as 40* BEFORE TDC on "EXHAUST" stroke correct?
Good oil flow, but timing events are different? Cam is old comp cams 20-247-4 SFT.
Any reason for concern?
69 and earlier balancer and tc. Engine is 70 340. Verified #1 TDC compression.
I can TRY to translate my method if need be lol.
Thanks
 
4spdragtop said:
OK, I'm a little stumped on this. Cam is degreed, adjustable rockers installed, thanks @CFD244 Troy for spacers but also for pushrod info lol. Lash is set .022. Solid flat tappet. When priming for oil with engine on stand, I have oil flow up to rockers, but not at the crank timing degrees that I have read.
From what I've read oil should flow at 90* BEFORE TDC compression #1 cyl for Pass side and 20* AFTER TDC EXHAUST #1 for drivers side.
If I'm doing this correct I am getting good flow, BUT
Pass side is 118* BTDC Compression
Drivers is 320* ATDC Compression, which is same as 40* BEFORE TDC on "EXHAUST" stroke correct?
Good oil flow, but timing events are different? Cam is old comp cams 20-247-4 SFT.
Any reason for concern?
69 and earlier balancer and tc. Engine is 70 340. Verified #1 TDC compression.
I can TRY to translate my method if need be lol.
Thanks
Click to expand...
Your question makes me wonder if all the oil holes are drilled in the same place degrees wise? Probably not. It's pretty ingenious when you think about it. Drill a hole in the cam to control the oil flow to the heads. (it doesn't need much) Just a squirt every 1/2 revolution.
 
You should be using your driver's side figures using #6 TDC and not #1.
 
That's what I'm wondering, no matter "when" the holes line up, it's getting oil. You once per 1/2 crank revolution? Isn't it once per full crank revolution?
I never thought to chk orientation of oil holes on cam lol
toolmanmike said:
Your question makes me wonder if all the oil holes are drilled in the same place degrees wise? Probably not. It's pretty ingenious when you think about it. Drill a hole in the cam to control the oil flow to the heads. (it doesn't need much) Just a squirt every 1/2 revolution.
Click to expand...

20240104_111111.jpg


20240104_111119.jpg
 
Some cam's have grooves machined between the oil holes. That's good for constant flow but it may be too much oil up top.
 
4spdragtop said:
That's what I'm wondering, no matter "when" the holes line up, it's getting oil. You once per 1/2 crank revolution? Isn't it once per full crank revolution?
I never thought to chk orientation of oil holes on cam lol
Click to expand...
FWIW - You have 3 oil holes in the camshaft journals. Or 1 full groove.
toolmanmike said:
Some cam's have grooves machined between the oil holes. That's good for constant flow but it may be too much oil up top.
Click to expand...
I have not had a problem with full groove camshaft oiling.
 
I watched a video from Nicks garage the other day, and this same thing was happening on a 440, he had no oil at the rockers @ the crank degrees it was supposed to happen at. After a lot of checking and prodding he eventually rotated the crank a couple of degrees and the oil flowed like a river.
 
4spdragtop said:
OK, turned over to 20* ATDC #6 exhaust, (which for verification purposes is 20* AFTER #1 compression correct??).
No oil flow.
Click to expand...
No. LOSE your #1 TDC reference regarding the driver's side oiling. Treat #6 like #1. Get it?
 
OK here is what I've read,
Pass side oiling is 90* BTDC #1 compression. I get 118* BTDC #1 compression (approx). So theoretically 28ish degrees difference.
Now for drivers side, I've read 20* AFTER TDC of #1 exhaust stroke. But Rob you are saying "#6" 20* AFTER TDC exhaust?
RustyRatRod said:
No. LOSE your #1 TDC reference regarding the driver's side oiling. Treat #6 like #1. Get it?
Click to expand...
 
Last edited:
FWIW, I’ve never bothered to check what the oil timing is on any Mopar I’ve put together.

I just slowly turn the engine over by hand while running the priming tool.
When oil starts flowing from one side……I verify oil is feeding all 8 rockers.
I install that side valve cover.

Then I keep turning the engine over while priming.
When I get oil flowing from the second side, verify all 8 rockers are being oiled….install valve cover……..done.
 
PRH said:
FWIW, I’ve never bothered to check what the oil timing is on any Mopar I’ve put together.

I just slowly turn the engine over by hand while running the priming tool.
When oil starts flowing from one side……I verify oil is feeding all 8 rockers.
I install that side valve cover.

Then I keep turning the engine over while priming.
When I get oil flowing from the second side, verify all 8 rockers are being oiled….install valve cover……..done.
Click to expand...
And it really doesn't matter what degree of rotation the cam is drilled at, as long as it is.
 
toolmanmike said:
And it really doesn't matter what degree of rotation the cam is drilled at, as long as it is.
Click to expand...

Right. As long as the two holes in the cam line up with the two holes in the block at the same time thats all that matters.

In other words, if the cam company got one of the two holes in the cam out of time you wouldn’t get oil.

Ive never seen that but it is certainly not out of the realm of possibility that it COULD happen.
 
PRH said:
FWIW, I’ve never bothered to check what the oil timing is on any Mopar I’ve put together.

I just slowly turn the engine over by hand while running the priming tool.
When oil starts flowing from one side……I verify oil is feeding all 8 rockers.
I install that side valve cover.

Then I keep turning the engine over while priming.
When I get oil flowing from the second side, verify all 8 rockers are being oiled….install valve cover……..done.
Click to expand...
This Steve.
I think most of the oiling/cam position talk stems from people not getting oil up top. I think you're good and i'd love to hear how that cam sounds when you gitter done. Gonna be sweet. :)
 
4spdragtop said:
OK here is what I've read,
Pass side oiling is 90* BTDC #1 compression. I get 118* BTDC #1 compression (approx). So theoretically 28ish degrees difference.
Now for drivers side, I've read 20* AFTER TDC of #1 exhaust stroke. But Rob you are saying "#6" 20* AFTER TDC exhaust?
Click to expand...
20 degrees after TDC compression for #6.

Per 70aarcuda Tony Santos (RIP).

“On a small block:
Turn the motor to 90* before top dead center coming up on #1 compression. The pass. side rockers should get oil.
Turn the motor to 20* after top dead center just past #6 compression. The drivers side rockers should get oil.”

That's top dead center of number SIX compression stroke, just like it reads.
 
PRH said:
FWIW, I’ve never bothered to check what the oil timing is on any Mopar I’ve put together.

I just slowly turn the engine over by hand while running the priming tool.
When oil starts flowing from one side……I verify oil is feeding all 8 rockers.
I install that side valve cover.

Then I keep turning the engine over while priming.
When I get oil flowing from the second side, verify all 8 rockers are being oiled….install valve cover……..done.
Click to expand...
Same here, but Tony (RIP) did and was good enough to share it. It can help tremendously in a diagnostic situation.
 
Thanks Rob, mine is slightly different, by approx 28* in both events, but as mentioned as long as both sides are fully oiled, which thankfully this is, so far anyway lol.
RustyRatRod said:
20 degrees after TDC compression for #6.

Per 70aarcuda Tony Santos (RIP).

“On a small block:
Turn the motor to 90* before top dead center coming up on #1 compression. The pass. side rockers should get oil.
Turn the motor to 20* after top dead center just past #6 compression. The drivers side rockers should get oil.”

That's top dead center of number SIX compression stroke, just like it reads.
Click to expand...
Thanks Rick, appreciate it. Hopefully it'll get buttoned up and in this summer.
OldmanRick said:
This Steve.
I think most of the oiling/cam position talk stems from people not getting oil up top. I think you're good and i'd love to hear how that cam sounds when you gitter done. Gonna be sweet. :)
Click to expand...
 
4spdragtop said:
Thanks Rob, mine is slightly different, by approx 28* in both events, but as mentioned as long as both sides are fully oiled, which thankfully this is, so far anyway lol.

Thanks Rick, appreciate it. Hopefully it'll get buttoned up and in this summer.
Click to expand...
That's all that really counts!
 
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