Hi all. I'm looking to replace the dead 350 in my old 87 Silverado. Needs new piston rings. I want to use a 5.3L LS engine from a newer truck, but I figured why not add a little spice to it first. However, there are some limitations I want to abide by. They are:
1. Can't harm the factory fuel mileage very much.
2. Can't harm engine longevity. I want the engine to last 200k miles or whatever the 5.3L is typically known for.
3. Can't harm the factory road manners. I want the factory idle, so no rough cam. No obnoxious racket or bad smells.
Even given those restrictions, I believe there is still room for improvement on the 5.3L LS engine. We just have to get into the details. For example, I don't want a loud exhaust, but that can be mitigated by using flowmaster hushpower mufflers. And I can't use a big cam, but there is room for a slightly larger cam that won't affect the idle any.
But what else? What all can I do to improve power, while not spraying much more fuel? Should I do a medium overbore on the cylinders? Polish the cylinder heads, but no porting?
What are all the specifics of such a build? Thank you
1. Can't harm the factory fuel mileage very much.
2. Can't harm engine longevity. I want the engine to last 200k miles or whatever the 5.3L is typically known for.
3. Can't harm the factory road manners. I want the factory idle, so no rough cam. No obnoxious racket or bad smells.
Even given those restrictions, I believe there is still room for improvement on the 5.3L LS engine. We just have to get into the details. For example, I don't want a loud exhaust, but that can be mitigated by using flowmaster hushpower mufflers. And I can't use a big cam, but there is room for a slightly larger cam that won't affect the idle any.
But what else? What all can I do to improve power, while not spraying much more fuel? Should I do a medium overbore on the cylinders? Polish the cylinder heads, but no porting?
What are all the specifics of such a build? Thank you
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