- Joined
- Jun 2, 2012
- Messages
- 25,363
- Reaction score
- 8,372
- Points
- 113
- Location
- canada
- Vehicle Year
- 1994
- Make / Model
- Ford
- Transmission
- Manual
I assume the red line mark on cam gear is the keyway
If so then yes it looks right, 50% of the time, lol
#1 exhaust would just be closing as #1 piston cam back to TDC, then #1 intake would start to open
The mark on cam gear would be at 4:00
But yes, for true #1 TDC Compression stroke both valves in #1 should have been closed 180deg rotation of crank
Intake stroke #1 at TDC, intake valve opens as piston goes down pulling in air/fuel mix
Compression stroke, #1 at Bottom DC, intake and exhaust valves both closed, #1 piston on the way back up, compressing air/fuel mix
#1 true TDC, both valve closed, spark plug fires
Power stroke, air/fuel explosion pushes piston down to add power to crank
Exhaust stroke, #1 piston at BDC, exhaust valve starts to open as piston goes up and pushes out exhaust
Every stoke of piston is 180deg of crank rotation, but only 90deg of Cam rotation
4-strokes of a piston requires 720 deg of crank rotation(360deg X 2), cam only rotates once, 360deg, in that 4-strokes
If so then yes it looks right, 50% of the time, lol
#1 exhaust would just be closing as #1 piston cam back to TDC, then #1 intake would start to open
The mark on cam gear would be at 4:00
But yes, for true #1 TDC Compression stroke both valves in #1 should have been closed 180deg rotation of crank
Intake stroke #1 at TDC, intake valve opens as piston goes down pulling in air/fuel mix
Compression stroke, #1 at Bottom DC, intake and exhaust valves both closed, #1 piston on the way back up, compressing air/fuel mix
#1 true TDC, both valve closed, spark plug fires
Power stroke, air/fuel explosion pushes piston down to add power to crank
Exhaust stroke, #1 piston at BDC, exhaust valve starts to open as piston goes up and pushes out exhaust
Every stoke of piston is 180deg of crank rotation, but only 90deg of Cam rotation
4-strokes of a piston requires 720 deg of crank rotation(360deg X 2), cam only rotates once, 360deg, in that 4-strokes
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