Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Compression Pressure
Maximum variation between cylinders is 20 lbs. (all engines) .
| 289" | 130-170 lbs. |
| 390" | 160-200 lbs. |
| 410", 428" | 170-210 lbs. |
| All Except 428" Police | (1) Hydraulic | |||||
| 423" Police (Cold) | .028" Int. & Exh. | |||||
| (Hot) | (2).025" Int. & Exh. | |||||
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| 289" | 18" at idle |
| 428" Police | 16" at idle |
| All Others | 17" at idle |
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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