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Old 05-15-2014, 10:23 AM
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The 1995's came both ways.Either flat tappet or roller.Both have the holes drilled and tap for a roller set-up.The upgrade considering your going to rebuild is the hydro roller cam.Also from 1996 to 2000 good set of heads that are not cracked.


The Vortec 5700 L31 (Vin code 8th digit "R") is a V8 truck engine. Displacement is 5.7 L. It is the last production Generation I small-block from Chevrolet. The cylinder heads feature combustion chambers and intake ports very similar to those of the LT1 V8, but without the reverse-flow cooling. As such, the L31 head is compatible with all older small-blocks, and is a very popular upgrade. It offers the performance of more expensive heads, at a much lower cost. It does, however, require a specific intake manifold (A 5.7L, 350 CI L31, Vortec engine has eight bolts attaching the intake manifold or four per head, as opposed to the traditional six bolts per head twelve in total found on older Chevrolet small blocks). The L31 was replaced by the 5.3 L 5300 LM7. The 2002 model year was the final year for the L31 5.7 L small block V-8 whose origins date back to 1955. The Vortec 5700 produces 255 hp (190 kW) to 350 hp (261 kW) at 4600 rpm and 330 lbft (447 Nm) to 350 lbft (475 Nm) of torque at 2800 rpm. It is currently being produced as a crate engine for marine applications and automotive hobbyists as the 'RamJet 350' with minor modifications. Known as the GEN 1+, this was the final incarnation of the 1955-vintage small block, ending production in 2005 with the last vehicle being a Kodiak/Topkick HD truck. Volvo Penta and Mercury Marine still produces the L31. The "MARINE" intake is a potential upgrade for L31 trucks. Using this "MARINE" intake will allow the use of common types of injectors with various flow rates while still maintaining emission compliance.

L31 applications:

1996–2002 Chevrolet Express/GMC Savana full-size vans
1996–1999 Chevrolet/GMC C/K full-size trucks
1996–1999 Chevrolet Suburban/GMC Suburban full-size long-wheelbase SUVs
1996–1999 Chevrolet Tahoe/GMC Yukon (and 2000 Tahoe Limited and 2000 Tahoe Z71 models) full-size short-wheelbase SUVs
1999–2000 Cadillac Escalade
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