#1  
Old 04-11-2019, 11:38 AM
TAQuest TAQuest is offline
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Location: Bay City, Michigan
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Quote:
Originally Posted by "QUICK-SILVER" View Post
The 455 I got to figure out and work on was built by a famous East Coast engine builder. The whole engine was a work of art, other than cam timing.
I rememberd his name from when I was a little kid. I thought he was an old man back then and surprised to hear he was still building engines in 1985 when the 455 came in the shop.

He wasn't the same man in 85 that he was when he was building winning race engines back in the 50's~60's.

Kinda sad, but at least he was still trying to do his best at something he loved to do.

"Old Age Happens"
Clay
You know Clay, when I moved the timing gear on the cam to line up the chain I had the distributor still in. The rotor didn't move very much at all. Not a big move.

What did you do to fix the 455? Did you degree the cam to make sure it wasn't some sort of custom grind that made it work better with the marks not lined up?


Last edited by TAQuest; 04-11-2019 at 11:56 AM.
  #2  
Old 04-11-2019, 12:34 PM
"QUICK-SILVER" "QUICK-SILVER" is offline
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Join Date: Feb 2008
Location: Alexander City, Alabama
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Originally Posted by TAQuest View Post
You know Clay, when I moved the timing gear on the cam to line up the chain I had the distributor still in. The rotor didn't move very much at all. Not a big move.

What did you do to fix the 455? Did you degree the cam to make sure it wasn't some sort of custom grind that made it work better with the marks not lined up?
After checking valve events during overlap I knew the cam was installed wrong. (posted directions for checking yours with the engine together).

Tore it down and set the gears/chain dots up and verified valve events during overlap by marking the balancer. Used the balancer like a mini degree wheel. Did that before putting the timing cover back. Used a piece of coat hanger and a short bolt to make a pointer. Middle timing cover bolt hole held the pointer just right for the balancer's O.D..

It took major carb tweaking, mixture screws and idle speed, for it to run at idle. Valve events happening at the wrong time had adjustments way off.

Picture intake valve opening happened early in the exhaust stroke instead of where it should have been during overlap. Exhaust pressure kept all the fuel/air from going in during intake. The exhaust pressure made the carb moan loud and stopped the engine from reving. Where the engine should have been making peak torque...It was starved for fuel/air and couldn't rev any higher.

Nothing custom about this. Just a mistake by the builder.

That help explain.. I wasn't trying to argue or be stubborn earlier in the thread. Just trying to get you to understand.
Clay

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  #3  
Old 04-11-2019, 02:15 PM
TAQuest TAQuest is offline
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Join Date: May 2005
Location: Bay City, Michigan
Posts: 1,000
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Quote:
Originally Posted by "QUICK-SILVER" View Post
After checking valve events during overlap I knew the cam was installed wrong. (posted directions for checking yours with the engine together).

Tore it down and set the gears/chain dots up and verified valve events during overlap by marking the balancer. Used the balancer like a mini degree wheel. Did that before putting the timing cover back. Used a piece of coat hanger and a short bolt to make a pointer. Middle timing cover bolt hole held the pointer just right for the balancer's O.D..

It took major carb tweaking, mixture screws and idle speed, for it to run at idle. Valve events happening at the wrong time had adjustments way off.

Picture intake valve opening happened early in the exhaust stroke instead of where it should have been during overlap. Exhaust pressure kept all the fuel/air from going in during intake. The exhaust pressure made the carb moan loud and stopped the engine from reving. Where the engine should have been making peak torque...It was starved for fuel/air and couldn't rev any higher.

Nothing custom about this. Just a mistake by the builder.

That help explain.. I wasn't trying to argue or be stubborn earlier in the thread. Just trying to get you to understand.
Clay
Really clear that they had exactly the same symptoms. Thanks.

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