RocBoy

iTrader: (1)

Help I just finished my t56 swap and now I have a bad vibration that comes on around 3500 RPM and grows considerably . This is what I had before the swap . 383 external balanced motor 427Hp 470torque , Whit a t-5 and edelbrock adjustable torque arm poly mount . I Had to use a balance plate between the crank and flywheel . I work well until the t-5 s**t the bed about 100 miles later .
Now I still have the 383 but I have a bad vibration . I am using the spohn cross member with the torque arm mounted on it poly end. I bought the center force fly wheel 700107 natural balance flywheel thinking I could still use the balance plate . Wrong clutch fork grinded on the pressure plate . After removing the tranny again I had the flywheel externally balanced to a 400 spec . The machinist drilled a bunch of holes in the back instead of adding a wight . He said he used a 400 crank and haromonic balancer . I have a feeling this may be the problem . I Have adjusted the pinion angel from -3 to +1 with all stops in between . I have herd the the spohn cross member will make a bunch of noise is this true . In natural I can rev the motor high and feel a vibration in the upper RPMs , but it is nowhere near as bad as it is in gear . When cruising over 90mph in 6th I feel another vibe that is at a lower RPM that definitely feels like drive shaft . The car feels like something is going to break and seems like its trying hard to rev passed 4000 RPM. Have any of you had to cut the 3gen drive shaft whith a t56.

91 1LE

iTrader: (1)

Your engine is out of balance. Further driving will destroy it and possibly your trans too. Your machinists theory of using a stock 400 crank and balancer to balance your engine is WAY off. You need to know the bobweights of your rotating assembly (rods, pistons, rings, bearings, and oil) to balance it. Your out-of-balance engine will destroy the main bearings if you continue to run it that way. You should disassemble your engine and have it professionally balanced along with the flywheel.

RocBoy

iTrader: (1)

My motor was built to use a 400 flywheel ,all the stuff in side in match weighed . I believe the guy that did the flywheel messed up . It work well with the balance plate . I just wanted to know if there was something else I should look in to before I bought another flywheel .