We chose the magic stick 3 camshaft for my new 408 Tx Speed stroker. After reading about all the EOIT information on the internet and studying the books I have on tuning, it appears to me that the "Boundary" should be set approx. 22 degrees earlier than stock because of how much earlier the inlet valve opens than stock, and that the "Target" needs to be set approx. 22 degrees later than stock because of how much later the exhaust valve closes than stock. To accomplish the latter, I must increase Target by a total of 44 degrees to make up for the amount the Boundary was reduced plus the additional 22 degrees of delay from stock setting. These changes are obtained in HP tuners by subtracting 0.25 reference periods from the stock Boundary setting and adding 0.500 reference periods to the stock Target settings. Narrowing the injection "window" on both ends, which is what this will do, makes a lot more sense for a performance camshaft with valves opening sooner and closing later than stock than what I've seen in most other posts. I will have my car running around the middle of next week and will let you know how this works.
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Originally Posted by JamesLinder
