Studs to bolt stock exhaust to aluminum heads

[northeastmopar]

Can anybody tell me if I can get studs which are 5/16 coarse to go into my edelbrock aluminum heads and have the 3/8 fine thread to fill the holes in a stock 1970 340 manifolds for the nuts to go on. I have the two long tube nuts and they are 3/8" I don't see any in the ARP catalog unless I am overlooking them?

 

[Bad Sport]

Do they need to be ARP? I would think those studs could be had at NAPA.

 

[younggun2.0]

i would at least want grade 8 hardware. I know the local nut/bolt shop here will make them.

 

[71swing]

Can anybody tell me if I can get studs which are 5/16 coarse to go into my edelbrock aluminum heads

Aren't your heads 3/8th as well?

 

[Oldmanmopar]

The holes in the manifolds are bigger for expansion so the studs do not shear from expansion and contraction. a special conical washer is used on the end studs only. The rest of the bolts do not get any. so you will need 4. make sure you use a exhaust stud. a carb stud will shear.

Cummin's diesels have very large spacers for the same reason. I have repaired many that have sheared. They sell two piece manifolds for them do to shrinkage from excess heat.

So this said don't try to perfect a design that is there for a reason. they will shear. Unless your afraid of the power and never get-em red.

5/16 studs 13/32 holes is the way they were designed. Use the conical washers.

Your welcome Steve

 

[Oldmanmopar]

If you need pics I have the factory hardware and manifolds here.