cam ID

I

Impalaroy

Member
I am working on a 1960 348 280HP engine.
Does anyone know the correct time (degree from TDC) when the exhaust and/or intake valve should begin to open?
I put a complete rebuild kit in from Kanter, and I had to set the ignition time to aprox 20 deg BTDC in order to develop any power at all. I advanced it until it pinged, and then backed it off. Even then it did not work properly. The engine runs fine at low rpm but has no real power. Is it possible that they sent me the wrong cam? Any ideas on how to find out?
I have established that the TDC mark is correct.
 
oldskydog

oldskydog

Well Known Member
Supporting Member 10
Impalaroy said:
I am working on a 1960 348 280HP engine.
Does anyone know the correct time (degree from TDC) when the exhaust and/or intake valve should begin to open?
I put a complete rebuild kit in from Kanter, and I had to set the ignition time to aprox 20 deg BTDC in order to develop any power at all. I advanced it until it pinged, and then backed it off. Even then it did not work properly. The engine runs fine at low rpm but has no real power. Is it possible that they sent me the wrong cam? Any ideas on how to find out?
I have established that the TDC mark is correct.
Click to expand...

Intake opens 18 degrees, 30 mins BTDC
closes 68 degrees, 30 mins ABDC

Exhaust opens 68 degrees, 30 mins BBDC
closes 25degrees, 30 mins ATDC
:coffee:
 
B

buildit

Well Known Member
Supporting Member 8
Cam Timing

A quick way to check your cam timing.
Pull left valve cover and distributor cap.
Turn engine so that rotor is pointing to #6 terminal with damper 0 mark EXACTLY at TDC. This puts #1 cylinder at TDC on overlap w/ both valves slightly open.
Lay a straight edge across #1 cyl rocker arms, directly above the pushrod tips.
The intake rocker arm should be roughly .010 to .015 higher than the exhaust if the cam is installed with 3 or 4 degrees advance.
If this is not the case, cam timing should be corrected.
 
I

Impalaroy

Member
cam time

Thanks, I will try that. I have used a protractor and a dial indicator to messure where the cam is at now.
The intake begins to open at 20 deg.BTDC, and completly closes at 90 deg ABDC

The exhaust begins to open at 71 deg. BBDC, and completly closes at 33 deg ATDC.

I'm not sure how to read the specs, but this does not look good to me.
Should I be reading 18 deg 30 min at opening beginning?
Should I be reading 68 deg 30 min at closing beginning?
etc.
Help if you can

Thanks
Roy
 
F

five-seven

Member
Cam specs

The way you state the way the car is responding with no power is that the cam may be in a retarded position. Did the timing chain have different set-ups for advanced 4 degrees and retarded 4 degrees? Sometimes it can be confusing and set wrong. Ask me how I know.
 
rstreet

rstreet

Well Known Member
Supporting Member 17
Sometimes it can be confusing and set wrong. Ask me how I know.[/QUOTE]

I have to hear this one:roll
robert
 
I

Impalaroy

Member
five-seven said:
The way you state the way the car is responding with no power is that the cam may be in a retarded position. Did the timing chain have different set-ups for advanced 4 degrees and retarded 4 degrees? Sometimes it can be confusing and set wrong. Ask me how I know.
Click to expand...

NO, the timing chain has no adjustments. I tried it with one link advanced, and that was too much. To make matters worse, I managed to break the positioning stud on the end of the cam.........:doh ....... I will order a new cam. any suggestions as to where to get the best one?
 
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