318 with PS.....What manifolds will fit?
So I settled on the 64-66 manifold plus 3/8” header flange for the drivers side and the 97 magnum manifold for the passenger side. What is the best way to source manifold studs? I have quite a few different lengths that I need now. Can I just get some 5/16 x 18 coarse threaded rod and cut them to length and crank them down with double nuts? Buy a generic kit? Is there something specific that I haven't come across? I appreciate the help!!
Just go to the parts store or a well stocked hardware store for the studs. For the driver's side, 3/8 longer than stock will get you there (studs are only used in the two end positions of the head), all you need to do is make up for the additional thickness of the header flange. If I remember correctly, I used 5/16x 1 1/2 automotive studs.
On the passenger side, a Magnum manifold does not use any studs, and if you did they would be so long that there'd be no way on earth you could ever pull the manifold off for any kind of service with the very limited amount of clearance between the manifold and inner fender, which would mean that you couldn't pull the head (for instance if you ever had to replace a head gasket), which means any kind of work on that side would require pulling the engine...
The stock manifold didn't have that issue because of it's relatively thin flange that in turn uses a shorter stud. The Magnum manifold's "flange" is probably close to two inches thick on the ends, so you'd need a three inch stud- and that adds up to four and a half to five inches of clearance you'd need in order to remove the manifold.
Long story short, just use bolts on the Magnum manifold, and sealer on the two end bolts.
And no, don't use All-Thread rod for this! It WILL snap, and then you've got to deal with drilling out the hole- not fun.
Studs are hardened and can take the tension from heat/cool cycles. And you only need two.