Flex plate/torque converter bolt size

[grubby65]

i have another post discussing washers behind the bolt heads mounting the torque converter to the flex plate. I took the car back to the transmission shop and what they ate telling me is the hole diameter in the flex plate is not standard. They used the washers for that reason. The engine is a 383 and the old torque converter was a TCI. MY question is what should be the diameter of the holes in the flex plate? Are there different sizes ?

 

[66Satellite47]

Low performance converters have 5/16" thread bolts. High performance converters use 7/16" bolts. I would expect that using washers would have the bolts contact the block. Not good. Use a good SFI rated flex plate.

 

[Yatzee]

Are you actually talking about "surface" washers or insert washers which are used to resize existing bolt holes If the convertor bolts are 5/16 and the holes in the flex plate are 7/16 best you go out and buy the proper SFI approved flex plate. You've obviously gotten the wrong one or the torque convertor is not for mounting on that plate.