LS motors are pretty renowned for their reliability, low cost and ease of making massive HP for cheap. I think you can get a used LS/tranny combo and then a conversion wiring harness for not much more than it costs to rebuild a 350 to comparable HP. Straight from the factory a 5.3L makes 310HP and 340 ft/lb of torque and gets better mileage than an older 5.7/350. They are also fuel injected from the factory which makes them more drivable and better on gas. Read this thread for more info... definitely makes sense. https://www.vanning.com/threads/ubbthreads.php/topics/750693/84-g20-ls-swap-project.htmlBetter mileage...Doubt that. My L31 350 always got 12-14 in town, 17-19 mpg highway in my 97 Express even with a cam, headers and tune with alot more power than stock.
1983 G20 Conversion Van, 350 TPI, Reed Hydraulic Roller cam, Ported 906 Vortec, Edelbrock 3817 TPI-Vortec Base, Doug Thorley Tri-Ys, Dual 2 1/2" exhaust, Speed Density 7730 ECM tuned by ME, 700r4 by ME, Stock 1,600 rpm converter, Rebuilt Stock 10 bolt with posi by ME, 3.08 gears, 358 RWHP @ 5,200, 384 RWTQ @ 3,400, 14.66 @ 95.43 w 2.28s 60'
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