- Jan 25, 2007
- 89
Cam positioning>>>
- Thread starter gbvetracer
- Start date
I'm pretty sure....
Mine has been inside the engine since my car was new. As I never exceed the redline I hope it stays in there for the duration of my ownership.
Chip
Mine has been inside the engine since my car was new. As I never exceed the redline I hope it stays in there for the duration of my ownership.
Chip
There was a discussion on this topic on one of the tech threads a while back, 'racer, but I'll be darned if I know which one/when.
'Afraid I'm going to have to suggest the tired solution "do a search".:frown
(Hopefully, someone else remembers the above thread/discussion a wee more specifically...)
'Afraid I'm going to have to suggest the tired solution "do a search".:frown
(Hopefully, someone else remembers the above thread/discussion a wee more specifically...)
Silverbullitt
GT Owner
Here is the thread:
http://www.fordgtforum.com/forums/showthread.php?t=5378&highlight=intake
I think you would have to use a degree wheel (pull the motor and remove the spark plugs) and remove the valve covers. Find #1 tdc with both valves closed. Then crank backwards until the #1 intake valve closes (opens going forward). Check the degrees at that point. there should be a spec somewhere for valve opening degrees. Then crank forward until the next cylinder in the firing order opens it's intake valve. It should be 90 deg (360/4??) from #1 if the engine is set to fire evenly. You need to go 2 rotations to check all cylinders. You really need to check one cylinder on each bank, but this might be an easier method so you don't lose count. I don't know the firing order and I don't know if #2 is next to #1 or on the other bank.
A compression test might easily and quickly tell the tale of short intake valve timing or differences.
Many of you were not on this earth when I rebuilt a Ford motor. And no it wasn't a flathead before the comedians get started.
http://www.fordgtforum.com/forums/showthread.php?t=5378&highlight=intake
I think you would have to use a degree wheel (pull the motor and remove the spark plugs) and remove the valve covers. Find #1 tdc with both valves closed. Then crank backwards until the #1 intake valve closes (opens going forward). Check the degrees at that point. there should be a spec somewhere for valve opening degrees. Then crank forward until the next cylinder in the firing order opens it's intake valve. It should be 90 deg (360/4??) from #1 if the engine is set to fire evenly. You need to go 2 rotations to check all cylinders. You really need to check one cylinder on each bank, but this might be an easier method so you don't lose count. I don't know the firing order and I don't know if #2 is next to #1 or on the other bank.
A compression test might easily and quickly tell the tale of short intake valve timing or differences.
Many of you were not on this earth when I rebuilt a Ford motor. And no it wasn't a flathead before the comedians get started.
Just as a historical note then, 'bullitt ... what particular pre-flathead Ford "motor" DID you first rebuild? :lol
(Why do I get the feeling paybacks will be hell?:shrug )
Silverbullitt
GT Owner
Caught me on that one pockets. Your car is now officially my parts car. Ok I have intimate knowledge of the hi po 289 271 HP family. I have changed spark plugs in a modular. The hi po is probably what got me here as a car guy. I worked my way through college as a mechanic. Once I graduated it became a hobby.
John at Accufab has done some research and testing on this issue. I believe he has found out that the cam timing from the factory is off considerably.
Basically a + 1; it's either the cam timing or the wrong cam grinds...
From what I heard on MF, most production Ford OHC motors experience incorrect cam timing from the factory, anywhere from 1-7 degrees off...
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