Cam Shaft 1974 455

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Larryd

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I have a 1974 455 with a bad lobe on the original cam and I can't seem to find a NOS cam or a GM part number for original cam or any good information on what would be best avenue to pursue. I have just purchased a NOS set of Hydraulic lifters as I didn't expect to have a bad lobe.
 
Did you look at NAPA or any of the chains?
Did you look at Sealed Power and Competition Cams?
Shouldn't be hard to find an aftermarket camshaft.
 
Well I was trying to avoid having to replace the cam bearings and possibly having to shift to different rocker arms if I went to aftermarket cam. This is a 1974 455 with 400 ram air heads. I was wondering if I could remove the cam that is in there now and have the 1 lobe repaired. The rockers are the 25lb tighten down. I have the 5/16 ball on ends push rods with pushrod guides so someone has fixed it up some.
 
Larryd said:
Well I was trying to avoid having to replace the cam bearings and possibly having to shift to different rocker arms if I went to aftermarket cam. This is a 1974 455 with 400 ram air heads. I was wondering if I could remove the cam that is in there now and have the 1 lobe repaired. The rockers are the 25lb tighten down. I have the 5/16 ball on ends push rods with pushrod guides so someone has fixed it up some.
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You don't have to replace the cam bearings or rocker arms unless the arms are worn. You have bottle neck rocker arm studs which is normal for Pontiac. A good cam for that engine and heads would be the equivalent to the 068 cam. That was used in Ram Air III 400's and 455 HO. You also have to use oil with high zinc/phosphorus content to prevent another lobe failure. I recommend Valvoline VR1 10W30 conventional.
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Ok I noticed the part number 9779068 which is an 068 S GM cam I think that is what you are discussing. I also noticed a 9779067 I assume that is a 067 P cam. And Finally 9785744 H GM cam. Today I pulled the cam today and it is a Comp Cams 268 H with 1 or more damaged lobes. I noticed 1 of the lifters was a bit concave. That was the lobe with the most damage. Also on my heads they are the J277 heads. Well any more advice you can give me would be welcome. I was going to research a possible NOS GM cam this evening I assume the best 1 to look for would be the 9779068. Also FYI I was running the Royal Purple 10w30.
 
I just read about the casting date October 2 1977. I haven't seen any GM 068 cams NOS . I haven't done a close inspection on the rockers yet. You say I don't need to be concerned on rockers unless the push rod wears through the rocker. Do you happen to know GM part number on those rockers. Also will I need to replace the nuts on the rockers or just retighten to I believe 25lbs.
 
Larryd said:
I just read about the casting date October 2 1977. I haven't seen any GM 068 cams NOS . I haven't done a close inspection on the rockers yet. You say I don't need to be concerned on rockers unless the push rod wears through the rocker. Do you happen to know GM part number on those rockers. Also will I need to replace the nuts on the rockers or just retighten to I believe 25lbs.
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Contact Butler, you are not going to find an OEM 068. Not just the push rod area but also the ball area. Consider new roller tip rockers.
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Do you happen to have a recommendation on antifreeze? I notice alot of deposits in the cooling system from using the regular Oreily antifreeze with 50/50 mix of distilled water and the antifreeze. Is there something that doesn't deposit on aluminum and steel. I use an aluminum radiator and timing chain water pump cover is aluminum.
 
Larryd said:
Do you happen to have a recommendation on antifreeze? I notice alot of deposits in the cooling system from using the regular Oreily antifreeze with 50/50 mix of distilled water and the antifreeze. Is there something that doesn't deposit on aluminum and steel. I use an aluminum radiator and timing chain water pump cover is aluminum.
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Are you using the cap that came with the radiator?
Does the Oreily say it's compatible with aluminum?
Have you looked for an anode?
 
Yes I am using the cap that came with the radiator. I will have to re-read the antifreeze container. I am not sure what you mean on looking for an anode?
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Ok I am studying the anode use for radiators. I will see what I can address with the anode addition. Thank you for the info .
 
By the way my 455 block 483677 h240. And heads are 6X j277. I have ordered the Mellings cam that supposedly mirrors the 9779068 from Ames. I will be putting in new Mellings 15:1 standard rockers in and new nos gm lifters . Also new standard pro steel billet timing chain . Do you have any words of wisdom on cam install and anything special I need to do to be successful.

Also it appears that a magnesium anode is correct as opposed to zinc. Is that correct. I was going to use prestone platinum 15 year antifreeze as it states it is safe for aluminum radiators and or aluminum within the cooling system.

Thank You
Larryd
 
Make sure you coat cam and lifters with installation lube and you can soak lifters in oil for 24 hours before install.
Look up Competition Cams or other manufacturer for breakin procedure.
 
Ok will do!
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I have replaced the cam with the Melling SPC-7 cam and I was following the instructions and I used the instruction to turn the oil pump with a drill and screwdriver to pump oil through the oil system to be sure it would flow through the oil system all of the way through the lifters and up the push rods and on to the rockers. So I did this and I notice the oil all flows out the hole in the bottom of the front plate of the cam and that concerns me that something might be wrong can you shed any light on this situation.
Thank You
Larry
 
Did you soak the lifters to prefill them?
How long did you spin the oil pump?
You are turning the drill counterclockwise?
You are using a 1/2" drill?
What brand lifters are you using? Came across a post about GM lifters causing too much oil restriction.
 
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I soaked the lifters for 5 days.
I spun the oil pump for 15-20 seconds until I spotted the big flow from the cam thrust plate then I stopped and checked my work and all looks correct so I ran pump 3-4 more times for 15-20 seconds or so.
I used a 1/2 inch drill but I didn't run it full speed counterclockwise maybe 1/3 speed .
I am using GM NOS lifters 5232265
 
Spin it longer and if you feel resistance it should be primed.
 
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