S3 and S4 cams are so good at cylinder filling, you don't need to bump up the timing to increse peak cylinder pressure. More timing gives you less power most of the time. The S3-4 JWT program gives you more bottom end and more power past the peak but has less timing at the power peak.Black200SXSER said:Why would you have to run 15 with a stock ECU...? it should be just like any other cam set..run it up to 17...
Hello sir,morepower2 said:
With no ECU, we have found with multiple dyno tests that 15 degrees is the best.