Intake/Exhaust Gasket replacement?

[Chewievette]

The exhaust side of my gasket is shot and I assume this also means there's damage to the intake side, resulting in exhaust gas ingestion by the motor and one of the contributing factors to the poor performance of my car. I have the new gasket already but I was wondering how much it takes to replace it? Do I acctually have to entirely remove the intake and exhaust manifolds or will I be able to just unbolt and pull them away from the head enough to take out the old one and slip in the new one? Basically I'd like to know if this is a one hour job or an all day job?

Thanks in advance.

btw: I have a '79 280zx.

[beandip]

If this is your transportation car , I recommend at least save it for a weekend. You could be lucky and be able to do as you said. However remember the car is 30yrs old and you could have some trouble removing all the bolts . If you snap one ,the one day job just got much longer. If the PO has replaced the bolts with studs this is in your favor, use lots of PB Blaster on the rusted nuts . my2c

[Ed]

I'm not sure on a 79'. But I would think that you would only be able to move everything back 1-2 inches without removing stuff. Then the studs would get in the way of "sliding out the old, and sliping in the new". Not to mention that you wouldn't be able to properly clean the mating surface. Personally I think it would be a pain in the donkey to try and slip it in & out. I might be wrong, I've only disassembled the FI intakes. Plan for all day, I say.

[Chewievette]

No, it is not my primary transportation. I bought the car as my project and I figure that replacing the gasket is a good first step. Not to mention much less noisy... But from what your telling me it sounds like I should just mark off a whole day on the calender to do it good and proper. I guess I'll be reading up on taking the manifolds off. If you've got any tips for this process I'd surely appreciate them.

Thanks.

[Ed]

I'd suggest getting some PB blaster and soaking the manifold bolts, exhaust flange bolts and any other bolts that you think you might have to take a wrench to. Put the front end up on jack stands just enough so that your not bent over all the way and enough where you can lay under the engine and get to those hard to reach bolts under the exhaust manifold.

[beandip]

Sorry I blew it . I dident see that you are driving a injected Z . Ed is right . To do a proper job it is best to pull the manifolds. Do by all means buy some PB Blaster for all the nuts and bolts. Let the stuff soak over night if you can and give it some more just before you start wrenching on it . It stinks to high heaven but you won't be sorry. Dont over tinghten the manifold when you reassemble everything. Manifold nuts torque to 8 lbs. One thing to do is to label the wireing and sensers as you remove the wires. Number them is a good way and be aware of the bolts lengths as they may not all be the same length. Important when reassembly. Also I use anti-seiz on all the bolts and nuts when reassembling. things go so much easier in the future if you need to remove something. Be careful not to scratch the aluminum head when cleaning the old gasket off and start tightning from the middle and work to the ends. Other than that , it's simple.