Harder to start when warm

[bigmoe]

08 5.3 LMG in my 65 GMC. Original harness, thinned. All stock except for intake and exhaust and the usual stuff removed from the original ECM. When cold it kicks/starts instantly with higher idle initially then settles down. When the motor is warm it takes about 3 seconds of crank or sometimes less and barely catches for a sec before it comes up to idle. Not a problem really just wondering why it does it.

[sprint_9]

Your intake and exhaust have affected things enough that your tune is no longer correct.