i'm going to swap my 350 with a 383,but i need a harmonic balancer. would the balancer on my 350 work on my 383. the crank is the one piece seal kind from eagle.

 

No. You'll need a 400 damper and flexplate.

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350 4 bolt main, Speed-O-Motive 383 stroker kit, re-sized rods ground for clearance,TRW Forged pistons,10.7:1 compression,HPC Coated RPM intake, Holley 750 cfm carb,World Products Sportsman II heads,2.02/1.60 valves, Comp Cam 1.6 roller rockers, Comp Xtreme 284 cam,240/246@.050 with .540 lift,Crane pushrods,ATI damper,Proform HEI and MSD6A box,HPC coated 1 5/8 headers, 2.5" exhaust with 40 series mufflers,TH350 with Hughes 3000 stall, Powertrax NoSlip Locker, 4.11 gears.