Vibration Diagnosing Help
I need a little help diagnosing my vibration. Seems between 2000 and 2200 are the worse in any gear. If you push the clutch in, and coast/idle, it's smooth. If I bring the rpms up to that rpm range with clutch still pushed in, the engine vibrates a little, but is really exaggerated when clutch is engaged and carries through the driveline and putting a load on it.
The 454 is externally balanced, stock rotating assembly, with stock damper, converted from auto to manual. The pulleys are a OE serp setup off a newer sbc and can't see any wobbling. And the flywheel and clutch are new, and those are balanced at the factory, right? When i installed the gear venders, i had a new shaft made and balanced. one thing I didn't do was install a 1/4" spacer under the tranny mount that came with the GV. Would raising the GV .25" make a difference? and only at certain rpms? There aren't different harmonic balancers for auto and manual?
I just don't know how I should go about diagnosing further
67 Chevelle 454, M21
Gen IV 454 (out of C30 ), 390 heads 1.88/2.19 valves by Vortecpro, with ISKY Hyd Roller cam (at 050 218 int./228 exh, lift 530 int./552 exh.), RPM performer intake, Fitech 600HP, Dougs headers, and M21, Gear Vendors OD, 3.73's, UMI Suspension, Viking coilovers.