Why LS Engines Are Great for Boost

• Strong blocks (iron & aluminum)
• Tons of aftermarket support
• Affordable junkyard availability
• Proven in 1000+ hp builds

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🏆 Best LS Engines for Boost

• LQ9 (2002–2007) – High-output 6.0L iron block, 10:1 compression
• LQ4 (1999–2007) – Same block as LQ9, lower 9.4:1 compression (better for big boost)
• LM7/L59 5.3L (1999–2007) – Cheap, everywhere, iron blocks handle boost surprisingly well
• LS2 (2006–2009) – Aluminum 6.0L, lighter, good aftermarket heads
• LS3 (2006–2015) – 6.2L aluminum, big power with mild boost
• LSA/LS9 (2009+) – Factory supercharged, forged internals

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📅 LQ9 Production Years & Models

• Cadillac Escalade (2002–2006, incl. EXT & ESV)
• GMC Yukon Denali & Denali XL (2002–2006)
• GMC Sierra Denali (AWD only) (2002–2006)
• Chevy Silverado SS (2003–2006)
• Chevy Avalanche / Suburban 1500 VortecMAX (2003–2006)
• Chevy Silverado / GMC Sierra VortecMAX (2006–2007)

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⚡ Easiest Junkyard Finds

• Escalade & Yukon Denali (2002–2006) → most common LQ9 source
• Sierra Denali AWD → decent availability
• Silverado SS / VortecMAX trucks → rarer, worth checking

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🔍 How to Tell LQ9 from LQ4 in the Yard

• RPO Code in glovebox/door jamb:
  • LQ9 = RPO “LQ9”
  • LQ4 = RPO “LQ4”
• Compression ratio: LQ9 = 10:1, LQ4 = 9.4:1
• Both are iron blocks and excellent for boost builds.

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⚖️ LQ9 vs LQ4: Which to Choose?

• LQ9 → slightly more power stock, higher compression (better N/A, but watch boost levels).
• LQ4 → lower compression, safer for big turbo builds, more common in junkyards.

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✅ Bottom Line

• If you want the quickest junkyard score → go for a 2002–2006 Escalade or Yukon Denali.
• If you want the cheapest iron 6.0 that takes tons of boost → grab an LQ4 from any 1999–2007 Silverado/Sierra/van.
• Either way, you’ll have a block that can handle serious boost with forged rods/pistons.