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1979 Ford Mustang - Cylinder heads

Hello,
This is a V6 engine 2.8 L (171cid).
in a 1979 Ford Mustang.
I need to replace both cylinder heads.
Some stores tell me both heads are the same, others that there is a slight difference.
I cannot find the right and left side together. I only have available 2 that are exactly the sane.
Since I have to buy by mail, I need to know in advance, if buying 2 igual heads is the right thing to do, and I would be able to install them and have the engine working allright.
Thank you ,
Best regards , Mario Bertotto

If it were me:
I would do both at the same time.
But I would take the current heads to a machine shop and have them rebuilt.

The listings I find do not show a left and a right head for the '79 2.8 engine. That means they are the same. To confirm, however, look for the casting numbers on the heads - usually found under the valve cover. If they are the same casting numbers, they are the same head.

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The castings will be identical. Any differences between the right and left side will be in what is bolted to them. It is possible that there could be machining differences too, but when they come out of the mold at the foundry, they are the same.

Edit: If you have aluminum heads, it is better to have them remachined. Aluminum seasons after awhile, 30k miles or so. After seasoning, they are a lot less likely to warp if overheated.

Can you please explain the reason for replacing both heads . . . ?

Are they cracked?

Do they just need a valve job?

Hello,

In first place , I do appreciate your interest and knoledge.

These heads are cracked , had been already repaired 3 times, and

the mechanic has told me that cannot have another repair because

they are barely holding together. All this caused by excesive overheating

from previous owner. This is the present condition of this heads.

Regards , Mario

If you have access to an auto parts recycler, they’ll have a computer database of what parts are compatible with what cars and engines. That’s probably where I’d start researching this problem. In my experience those folks are very happy to help. I guess they’re thinking with the info they provide you’ll soon be back and buying some parts from them. I’d also buy some of those classic Mustang restoration magazines I see in the bookstores, magazine stands, and look through the advertisers. Some of them will probably be selling heads, and they’ll have a lot of experience with this sort of thing, as they deal with it every day.

The AutoZone website shows one part number so this means the heads should be identical left and right.

However, there is a footnote regarding the VIN. The VIN must be provided to get the right heads.
This means there was a mid-year production change in the heads. What that change is I do not know.

Had them fixed by shop 3 times? Can they source heads for you?

Thank you . Very usefull your comment. The car was manufactured February 1979 so I Will

asume that the mid-year change you are writing about does not apply to these heads.

Mario B

Thank you for your interest and sugestions. I am sure I Will be making the

right decisión with them.

Mario B

Hello Keith,

Thank you for your answer . Very usefull.

          Mario B

Thanks for your answer , Mustangman.

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​I appreciate your advice. Regards Mario B

​Hello Cavell,

They fix the cracks screwing bolts side by side along the crack.

But now they are in the limit. Heads are now too week and narrow.

Cannot be machined again. I don’t beleive they got sourced.

Thanks for writing,

Mario B

The Ford part number for those cylinder heads is D7ZZ-C049A.

You can perform a search with that number, it fits 1977-1979, both left and right sides.

At this point, have you considered looking for a rebuilt/remanufacture long-block?

​Yes. A 305 cid or 350 cid V8 would be the options. The point is

how to match the higher power and rpm settings of the new long-block

with the existing C 3 automatic transmition that has already been

rebuilt. If the engine-wheal relation of the gears and the torque

convertor, as well as the parts resistance, will still be suitable with

the V8.

Let’s clear up something, please . . .

I just did some quick research, and you appear to have a 3rd gen Mustang, in other words a Fox-body, is that correct?

As such, I’m not seeing either a 305 or 350 as factory options, for what it’s worth

You’re planning on dropping in something that will easily fit, an engine that was originally a factory option, right?

If that is indeed what you want, how about dropping in a 5.0 crate motor, preferably one of the later “high output” versions . . . ? I’m sure it’s already been done by lots of guys. So motor mounts and wiring harnesses should be readily available, probably from aftermarket companies. The name painless wiring comes to mind

I meant a rebuilt 2.8. Please do not put a SBC in a Mustang.