Oh one thing to add True Double Roller. 
BB Timing chains
Thread Starter
Le Mans Master
Joined: Dec 2006
Posts: 8,837
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BB Timing chains
Last Saturday I went to another CF members house to help install a manifold and rebuilt Dizzy. As soon as I looked under the hood at that BB 454, I was back in High School working at a service station.
We had an account, fleet of BB 1 Ton trucks we serviced. I remembered changing an exhaust manifold, or timing chain at least once a month in 1 of their trucks.
I shared this story with John, and we decided while the manifold was off, why not take a look see. The valley has a nice 1 1/2" hole in the front, right behind the cam sprocket.
Here is what we found.
Now one of the Generals not so bright ideas was to make the cam sprocket out of aluminum, with nylon teeth, for a quieter engine.
STUPID. This engine has 58,000 documented original miles. The slack in the timing chain was so bad, I almost slipped it off the cam sprocket.
Some of you have PM'd me concerning timing difficulties with your BB motors. If you have this original set-up in this condition, your dizzy will never be able to perform it's function.
We had an account, fleet of BB 1 Ton trucks we serviced. I remembered changing an exhaust manifold, or timing chain at least once a month in 1 of their trucks.
I shared this story with John, and we decided while the manifold was off, why not take a look see. The valley has a nice 1 1/2" hole in the front, right behind the cam sprocket.
Here is what we found.
Now one of the Generals not so bright ideas was to make the cam sprocket out of aluminum, with nylon teeth, for a quieter engine.
STUPID. This engine has 58,000 documented original miles. The slack in the timing chain was so bad, I almost slipped it off the cam sprocket.Some of you have PM'd me concerning timing difficulties with your BB motors. If you have this original set-up in this condition, your dizzy will never be able to perform it's function.
Race Director
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From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
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Great pics....better drop the pan and clean out the oil pump pickup. Guess where all that plastic is???
JIM
JIM
Race Director
Joined: Nov 2002
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From: Taylor Michigan
That type of timimg gear is standard equipment on all Chevrolet V8`s. Just change it to one from a truck or any other steel gear setup and you will be fine. But remove the broken nylon pieces from the oil pan too.... .
.
Thread Starter
Le Mans Master
Joined: Dec 2006
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Pan is off. We are done going backwards. Tomarrow the new chain goes in. Parts per Iron Cross instructions.
I just wish it was a pick-up, not a Vette. They must have used shoe horns to get that thing in there.
I just wish it was a pick-up, not a Vette. They must have used shoe horns to get that thing in there.
Le Mans Master
Joined: Oct 2002
Posts: 5,714
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From: Silver City NM
St. Jude Donor '05-'07
Of course, it you want the "turbine sound", you can always go with a full gear drive setup
http://www.milodon.net/geardrives/pg44.htm
http://www.milodon.net/geardrives/pg44.htm
Thread Starter
Le Mans Master
Joined: Dec 2006
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It's a nice, pretty unmolested #'s matching 72 454. He wants to retain the stock appearance.
Next decision up for grabs. The valves are pretty grungy for the milage. I know the valve seals are gone/turned to stone. The engine runs strong, and it does not smoke/use oil. Just a puff on start up.
I am tempted to do just the seals on the car, not a valve job. I am willing to bet the guides are fine. Opinions.(I know there is no shortage of em).
Next decision up for grabs. The valves are pretty grungy for the milage. I know the valve seals are gone/turned to stone. The engine runs strong, and it does not smoke/use oil. Just a puff on start up.
I am tempted to do just the seals on the car, not a valve job. I am willing to bet the guides are fine. Opinions.(I know there is no shortage of em).
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Race Director
Joined: Nov 2002
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From: Taylor Michigan
Of course, it you want the "turbine sound", you can always go with a full gear drive setup
http://www.milodon.net/geardrives/pg44.htm
http://www.milodon.net/geardrives/pg44.htm
......
Pro
Joined: Dec 2006
Posts: 582
Likes: 3
From: Glen Allen (Richmond) Virginia
It's a nice, pretty unmolested #'s matching 72 454. He wants to retain the stock appearance.
Next decision up for grabs. The valves are pretty grungy for the milage. I know the valve seals are gone/turned to stone. The engine runs strong, and it does not smoke/use oil. Just a puff on start up.
I am tempted to do just the seals on the car, not a valve job. I am willing to bet the guides are fine. Opinions.(I know there is no shortage of em).
Next decision up for grabs. The valves are pretty grungy for the milage. I know the valve seals are gone/turned to stone. The engine runs strong, and it does not smoke/use oil. Just a puff on start up.
I am tempted to do just the seals on the car, not a valve job. I am willing to bet the guides are fine. Opinions.(I know there is no shortage of em).
I wiggled each valve stem side to side when the spring was off and found many worn stems. The small block needs a valve job.
IF there is some money available on this project and If you are telling us that the manifolds are off then why not pull the intake and slip those heads off? Also If I had the oil pan still off I would consider a fresh oil pump and get that brittle plastic sleeve replaced on the oil pump shaft.
Thread Starter
Le Mans Master
Joined: Dec 2006
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I just put valve seals on a buddy's 58,000 mile '72 small block that was doing the puff on startup thing. The motor was VERY clean inside and half of the valve seals had turned to stone.
I wiggled each valve stem side to side when the spring was off and found many worn stems. The small block needs a valve job.
IF there is some money available on this project and If you are telling us that the manifolds are off then why not pull the intake and slip those heads off? Also If I had the oil pan still off I would consider a fresh oil pump and get that brittle plastic sleeve replaced on the oil pump shaft.
I wiggled each valve stem side to side when the spring was off and found many worn stems. The small block needs a valve job.
IF there is some money available on this project and If you are telling us that the manifolds are off then why not pull the intake and slip those heads off? Also If I had the oil pan still off I would consider a fresh oil pump and get that brittle plastic sleeve replaced on the oil pump shaft.
We are changing the rear seal today.
Last edited by Big2Bird; Apr 5, 2007 at 10:13 AM. Reason: Add
Le Mans Master
Joined: Oct 2002
Posts: 5,714
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From: Silver City NM
St. Jude Donor '05-'07
Dep
Le Mans Master
Joined: Oct 2006
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From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
If the guides are really worn, seals won't help for long. A good set of Perfect Circle seals on any Chevy will help. To really check the guides, the heads need to be on the bench, springs off, and lift the valve off the seat. See how much slop there is. On the seat, or too far off the seat, ( I forget what the actual spec is), and you get phony readings. The valve has to be in it's normal range of travel, but off the seat to really know how loose the guides are.
GM used those )(*#&$^ nylon covered gears in everything I can think of. I've taken the chain off with both gears still installed. On my stuff, or anything that had any kind of performance, I always go back with a double row roller chain, Cloyes, TRW, even GM has them.
GM used those )(*#&$^ nylon covered gears in everything I can think of. I've taken the chain off with both gears still installed. On my stuff, or anything that had any kind of performance, I always go back with a double row roller chain, Cloyes, TRW, even GM has them.
Le Mans Master
Joined: Oct 2002
Posts: 5,714
Likes: 6
From: Silver City NM
St. Jude Donor '05-'07
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
I just looked at Comp's catalog. They show both a double roller chain AND a Morse-type. Which one did the speed shop sell him? Personally, I'd go with the double roller, but that's just me. I don't think there is anything wrong with the Morse chain and steel gears.
Thread Starter
Le Mans Master
Joined: Dec 2006
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John??????????????????????? Part #?