Generally speaking, Short Tube Headers will produce more upper RPM power than Long Tube Headers, which produce more low end torque...However, the primary tube size of 1-3/4 on the LT vs. the 1-5/8 ST should help the Long Tube Headers outperform Short Tubes accross the entire RPM range...In theory, of course.adearmas said:I see younhave long 1 3/4 headers. Some people have 1 5/8 short headers. Why the difference. Why would I want a long vs a short and viceversa. What is the purpose? How that difference affects performance? If you change headres, exhaust and air induction do you have to reprogram the cars PCM?