other than clerance between the pump and torque converter what can cause the drive tangs on the pump to break. Could a misaligned drivetrain cause it, this has occured with different engine blocks, transmission cases converters ect. The driveline alignment is the last thing I can think of just not sure it could cause it.
a stock converter modified to a 2500 stall speedway flex plate and the dowel pins are good and the runout is .002 on the converter.
What is the pull up dimension on the converter install? How far (exactly!) is the converter behind the flywheel when fully engaged into the pump ( not bolted to the flywheel)?
Has anyone inspected the slide in the pump? Absolutely no wear or high spots allowed. These cause the vanes to catch in the slide bore and break the rotor
all of the pumps have been new 10 vane pumps except for the last one which was in a stock pump in a stock trans pulled from a van with a blown engine. the pull-up has been either 1/18 or spaced out to 3/16 in various forms as we have chased the issue. 292 six cylinder under 300hp runs fine no vibration only breaks when you get on it hard.
With 1/8" pull up it ain't likely an installation problem. If you got .002- with the converter bolted to the flex plate and the flex plate bolted to the crank flange- it ain't likely a flexplate problem. With new dowells the only way that the transmission could be misaligned is if the block or transmission case was made wrong at GM-not likely. The converter is by virtue of being "modified" suspect. The process of elimination leaves little else.
This is your clue Hard accel causes rapid line rise; pump slide goes to max. crashes into rotor or vanes, you know the end. This failure is caused by an internal pump clearance issue
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