I was an early adopter of the Z1 CSCEK. I went through 4 cylinders in about 50K miles. Had external plastic shell leak as well as internal seals leak. Z1 only replaced the first one at their expense. The last three I paid for out of pocket. I purchased the ZSpeed CMAK a few months back to replace it.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |