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Old Jul 10, 2023 | 09:20 PM
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Steinberg 21's Avatar
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Default 5.3L Lm7 (gen 3)

hey i was just wondering what people have done with their motors to make between 500-750hp (reliable)

have heard the stock crank can handle up to 1000hp

someone also told me that if you put in a new camshaft, piston/rods (10-1comp) 75lbs injectors and getting in tuned properly that tpu can make upwards to 500hp
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Old Jul 11, 2023 | 12:01 AM
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The LM7 has 9.5:1 compression. You will need better heads and bigger cam.
The LS7 which has 505 HP only has 42# injectors, so 75# might be a bit much.
Read some build threads here for engines about your size. Don't depend on "someone told me"
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Old Jul 11, 2023 | 05:30 PM
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someone also told me
Someone is pumping your anus full of sunshine.

Anything very much over 400 out of a 5.3 is kind of a stretch, on pump gas, in a real-world car you can drive on real-world streets in the real world, and without some kind of The Force. Especially for someone with no experience.

Add blowers or turbos, or nitrous, it becomes a whole other ball game. Blowers especially are pretty close to a bolt-on.

OTOH, by the time you buy flat-top pistons and do the machine work, you're already into it for more than a LQ9 core; but still have 0.7L less.

What is this going in? What is it replacing? What's around it? (gears, converter, exhaust, etc.) What is it going to be used for? How much money are you willing to sink into it? How much are you willing to change the rest of the vehicle?
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