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I have removed all the nuts from the intake and exhaust manifolds. I even got the nut hidden under the heat riser against the block.

I can’t seem to get the manifolds off. I have been tapping on them with a rubber hammer and prying some here and there. But I don’t want to go crazy prying on the side of the block. I have gotten it to where on all but the front most manifold connection when I spray PB Blaster it disappears into where the gaskets are. The front one seems to be a pain in coming loose.

Any tricks you guys have to get the intake and exhaust manifolds loose?

Having removed a few of these, I'd guess that one or more of the studs has rusted to the manifold(s), and is making life difficult.

There are thirteen studs that hold the combination intake/exhaust manifold assembly to the block. I count the number of nuts (or nuts that have corrosion welded to the studs, causing the entire stud to come out when trying to remove the nut), and make sure I have the total before I start banging on the manifolds.

I use a dead blow hammer, or if that doesn't work, a small brass hammer.

It's stuck on the two longer center studs through the manifold.
Keep soaking those two and working the manifold with a "slight" pry
Front, center and rear. pry out tap back. take your time to let the
build up of rust clear from the two holes.
Tom

All the nuts are off except for the three studs that came out with the nuts. I decided to use a torch to heat the ends of the studs that are still there. I got them hot but not too hot. Then I followed up with sprays of the PB blaster.

I did this about three times and using a plastic dead blow hammer I am getting movement on the intake and exhaust. It just won't come free. I will keep heating and spraying then following that with the dead blow hammer and let you guys know. I think it is just a matter of time now.

Which three studs came out with the nuts? For me, those two long ones in the 2/3 and 4/5 exhaust manifold ports are always a problem.

Just wondering why you heated the ends of the studs? Wouldn't that heat expand the OD of the studs, and make it harder to pull the manifolds off of them?

The studs that came out were the two on the rear exhaust fitting and one on the front intake.

I was heading the studs and letting them cool so it might loosen any rust and they might draw in the PB blaster.

Got it. That makes sense.

If the PB Blaster doesn't work, I've had good results using Aerokroil. I have a can of each, but the Aerokroil seems to work where the PB Blaster sometimes doesn't.

I am down to one stud that is not loose. Its one of the long ones under the exhaust manifold in the front middle.

I have been whacking on the headers with the shot filled rubber hammer, heating and then letting it cool and spraying it with PB Blaster then a mixture of ATF and Acetone. That one stud is being a pain. All the other suds are moving in their holes when I pry on the header.

My next plan is to try and weld a bolt to the end of the stud and back out the stud.

I took a break and ate supper then went back at it. Earlier I had been using a slide hammer with a short piece of chain around the exhaust manifold. It was not budging anything.

When I got back at it I was using the slide hammer. I noticed the manifold was pulling off of that last stud just a little. So I kept at it and it finally came off. I uploaded two pictures. On the second one you can really see on the right the long stud how it was rusted to the manifold.

Congrats on getting those manifolds off.

Assuming that you're going to remove and replace those studs, apply generous amounts of penetrant to the threads at the block, and allow plenty of time for it to work. You'll probably also need to apply some heat to the block area around the stubborn studs. A good quality collet-style stud remover (like a Snap-On CG500 set) will help avoid breaking off a stud. I know, those stud remover sets are not cheap, even used, but a stud broken off in the block is no fun. I've gotten a lot of use out of my set, and have never broken a stud with it.

You probably know this already, but VPW sells a set of new stainless studs along with the brass washers and cups.
Was well worth it in my opinion!

Pulling the studs was a nail biter...