Old 5.7 TBI vs Newer 5.3 - at 2200 rpm?

[ccreddell]

Think about it in terms of stroke length. A 5.7 has a stroke of 3.48". A 5.3 is 3.622". So the 5.3 has the advantage right out of the box. All things being equal, the 5.3 will have more torque. But things arent equal. The 5.3 has better heads and a better fuel injection setup so its better still. And if you are going to go through the trouble of swapping engines, and arent willing to put a cam into it that addresses your specific needs, then why bother.

[blacstar]

well from owning both a 1994 5.7 reg cab 5 speed and a 2007 classic 5.3(swapped) 5-speed. the power band in the 5.3 is wider than the 5.7. both engines in stock trim pulling the same weight( gsxr600 in the bed, 2 gsxr 1000;s on the trailer); i kinda struggled in the 5.7 to get up to 100mph in 4th/ cruise in 5th @100 with the 5.3. plus the efficent 5.3 is roughly 5-7mpg better pulling the weight mentioned above.

[canada4g63]

If you have access to a cheap 5.3 then go for it but not sure if your trans will work with it so you have to keep in mind a new trans to. I put a cam/header bolt on in my TBI, has pleanty of towing power.