flex plate over torque

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evren

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Location
San Diego
First Name
evren
Truck Year
73
Truck Model
c30 Cab and Chassis
Engine Size
292
I installed my 350 engine with a th350 trans into my 73 C30 last weekend. Then engine and tranny are from another truck. I couldn't find many of the torque specs in may Haynes manual and google came up with a bunch of different answers. For the the torque convertor to flex plate bolts I thought I finally found the right torque - google said 75 ft lbs. Seemed high for 3/8" bolts but there's a lot of forced there so maybe it wasn't crazy. I could not get the torque wrench to click and having broken so many bolts in my life I didn't force it - it was clear something was wrong.

I finally found the right torque - 35 ft lbs - so I took the bolts off, replaced them and also tried to rotate the torque convert by 60 degrees to use the other set of welded on nuts. But it looks like I may have damaged the flex plate. I think it will be ok but wanted to get some opinions from folks that know better than to try to torque small nuts to 75 ft lbs.

Pictures attached.
 

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Chevy 88

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Location
Canada
First Name
f7t6
Truck Year
1988
Truck Model
GMC
Engine Size
350
Not ideal, but not bad. Bolt it up. Should be fine. I would use some sort of medium strength lock-tite / threadlocker / etc.
 

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