1949 Plymouth manifold question

[TodFitch]

The washers with a cone shaped hole are for the most forward and rearward studs. A special nut with a conical shape is used for those. The flat washers are for the other studs. You can get the entire kit from Vintage Powerwagons.

I am not sure when they started using the special fasteners. The 1933 parts book just shows the use of brass nuts for all manifold studs.

The main thing is that these nuts are should not be tightened so much that the manifold can't expand and contract with temperature. The torque spec is only 15 to 20 ft-lbs.

[jkogden]

Can anyone tell where the different size washers are used See pictures.  Also Can I use regular nuts or are there certain types of nuts used on the manifold. I thought I read somewhere in this group that the outer nuts were different to allow for expanding from the heat. Thanks on advance
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