- Joined
- May 19, 2021
- Messages
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- My Car
- 73 Grande will be used to build 73 Vert.
Hello:
I’ve posted this over at VMF, but wondered if I’m missing some valuable eyes on my problem? Anyway, if you’ve follows by build, you know I swapped the drivetrain from an 87 TBird 5l Speed Density system into my 73 Grande. I’m sorting out I believe to be a vacuum leak(s), but after two day, and testing everything I can think of, only finding one leak that gave me 2” more vacuum (10 to 12”), I’m wondering if the condition of the motor is the culprit.
The car is hunting for a steady idle, now has 12” vacuum, is lumpy on the idle, and when I connect the timing light, it’s very close to 12 degrees BTDC, but moves up and down 2 or so degrees each way as it hunts.
Now, to be clear, besides taking the top of the manifold off, change the oil pan, new pump, new pump shaft, new timing chain set, and new harmonic balancer, I do not know the condition of this ~75k motor. For all I know, 12 may be good. If it is, what can I do to smooth out the idle?
Here are two videos of it running, first focused on the vacuum gauge, (it’s hard to see this 1970 Craftsman gauge, the plastic lenses if scuffed) reading 12”, and the second is the tach showing how much it’s hunting, and the second shows how much idle charge it’s experiencing. Any ideas or further questions are welcomed (and I still have no codes using my OBD1 reader). Thanks.
View attachment IMG_2371.mov
View attachment IMG_2372.mov
I’ve posted this over at VMF, but wondered if I’m missing some valuable eyes on my problem? Anyway, if you’ve follows by build, you know I swapped the drivetrain from an 87 TBird 5l Speed Density system into my 73 Grande. I’m sorting out I believe to be a vacuum leak(s), but after two day, and testing everything I can think of, only finding one leak that gave me 2” more vacuum (10 to 12”), I’m wondering if the condition of the motor is the culprit.
The car is hunting for a steady idle, now has 12” vacuum, is lumpy on the idle, and when I connect the timing light, it’s very close to 12 degrees BTDC, but moves up and down 2 or so degrees each way as it hunts.
Now, to be clear, besides taking the top of the manifold off, change the oil pan, new pump, new pump shaft, new timing chain set, and new harmonic balancer, I do not know the condition of this ~75k motor. For all I know, 12 may be good. If it is, what can I do to smooth out the idle?
Here are two videos of it running, first focused on the vacuum gauge, (it’s hard to see this 1970 Craftsman gauge, the plastic lenses if scuffed) reading 12”, and the second is the tach showing how much it’s hunting, and the second shows how much idle charge it’s experiencing. Any ideas or further questions are welcomed (and I still have no codes using my OBD1 reader). Thanks.
View attachment IMG_2371.mov
View attachment IMG_2372.mov