383 / 440 Exhaust Manifold Original Equipment Studs and Nuts

[Needa68]

Hi: We're looking for a bit of assistance.

We have a 440 engine in which the exhaust manifolds are mounted with bolts instead of studs and nuts. Water has been seeping out from around the bolts. Consequently, we ordered an original equipment twenty-four piece set of studs and nuts to replace the bolts.

Three of the twelve nuts have extenders. One is two inches long. Two others are two and seven eight inches long and have threads in both ends.

Our questions are these. On which studs are the three nuts with the extenders used? What connects to the threads in the top of the two longest nuts?

Any insight into the use of the nuts with extenders you might be able to provide would be greatly appreciated. Thank you!

[ACUDANUT]

When you bolt these on, you will see where they go.

Also, use gasket sealer when inserting the studs.  Without this, you might have anti-freeze leaking out around these studs.

[Needa68]

ACUDANUT: Thanks for responding. We were hoping for a more specific answer to avoid trial and error. Hopefully we are intuitive enough to do as you suggest. Again, thanks for responding.

[XH29N0G]

I don't know if this helps.  I just looked at the manifolds that came off my engine.  The back hole on the driver's side extends through the manifold and the 4th and 5th ones on the passenger side look the same.  I took a quick look in the Factory Service Manual (1970) and there is a bit of a cryptic picture that may explain some more.  There is an intake air heater that drew air up from around the driver's side manifold and I wonder if this is part of the issue. 

[A383Wing]

ACUDANUT: Thanks for responding. We were hoping for a more specific answer to avoid trial and error. Hopefully we are intuitive enough to do as you suggest. Again, thanks for responding.

look at the exhaust manifolds stud holes and will will be pretty obvious to what nuts go where...all of the studs should be same length.

and all this depends on whether you still have the OE original manifolds on the car and have never been changed out to something else

you never stated what car you are working on here, nothing should go on top of the longer nuts unless it's got a pre-heat tube

[ACUDANUT]

I thought we were talking about the HP manifolds for reason  . Sorry about that. You never stated which type you had though.  If I were you, I pay the money and get the HP manifolds. 

[Mopar Nut]

If I were you, I pay the money and get the HP manifolds. 

[Needa68]

My bad! I should have given more details about the exhaust manifolds used. The engine is 70's model 440 cid that we got out of a 65 Chrysler. In the early 80's the Chrysler's original 413 engine was replaced with the 440 but the original exhaust manifolds were retained and used. When we swapped the 440 into our Charger we also used the older exhaust manifolds. We kept and used them because we had them and because horsepower wasn't one of our prime objectives. We were building a cruiser / show car (modified class).

In retrospect purchasing the 68-70 exhaust manifold stud / bolt set was a mistake and to some extent a waste of money. I simply forgot we had used the older manifolds even though I see them almost daily. I'm not going to say age is an issue here but things like this seem to be happening more and more often these days.

Everyone's feedback is appreciated. Thank you! RHM, Jr.

[fy469rtse]

Yep the only advice I can give is drain coolant to a level below heads,
Seal the studs , some of them go through to water jackets in head , need to seal these properly , as stated above