Just ordered my 408 and cam from TSP
Mar 10, 2021 | 09:59 AM
#21
Just to bump this to the top
the 408 runs, kind of! Half the motor is still unused
To explain further, the 408 got a custom cam from Pat.G 236/241 .600/.600 114+3 and installed in my C5. During our first start excursion last weekend, we found the car running on 4cyls. Cyls 1/5 and 6/8 werent hitting. Verified spark and power to the injectors, verified compression, concluded the PCM wasn't pulsing or wasn't able to pulse the injectors. Verified with a noid light
Swapped Tahoe and C5 PCMs around, verified PCM hardware is fine; bricked the C5 PCM in the process
150-160psi across the board; which is pretty good for a motor without seated rings and the throttle closed during the comp test. Next up is verify continuity between injectors and PCM and fix any issues, unbrick ECU and try again
Guess I can't sell the 408 as "unused" anymore, except 1/2 the motor is still fresh
the 408 runs, kind of! Half the motor is still unused
To explain further, the 408 got a custom cam from Pat.G 236/241 .600/.600 114+3 and installed in my C5. During our first start excursion last weekend, we found the car running on 4cyls. Cyls 1/5 and 6/8 werent hitting. Verified spark and power to the injectors, verified compression, concluded the PCM wasn't pulsing or wasn't able to pulse the injectors. Verified with a noid light
Swapped Tahoe and C5 PCMs around, verified PCM hardware is fine; bricked the C5 PCM in the process
150-160psi across the board; which is pretty good for a motor without seated rings and the throttle closed during the comp test. Next up is verify continuity between injectors and PCM and fix any issues, unbrick ECU and try again
Guess I can't sell the 408 as "unused" anymore, except 1/2 the motor is still fresh
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