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Bumping up the 318 a bit

Got a 24" breaker bar. Much nicer to work with but the mail took forever. Anyway, head bolts are out and one head is off. The pistons appear to have plenty of carbon on them - I've never been into an engine this far before, but I'm guessing that's what it is. I was hoping to see some cross hatching on the cylinder walls, but none is apparent.

View attachment 1610768

View attachment 1610769

I'm having trouble getting the driver's side head off. I watched a Slantfish video on Youtube and he had the same problem with the driver's side head. He worked a drywall putty knife under the head until it loosened up. I haven't had any luck with that yet.
just a thought, if the spark plugs are in head and the rocker train removed, if you turned the engine with a socket and breaker bar would the compression break the seal ? but make sure all the bolts are out first!! i’ve never tried this but seems reasonable?!?!
 
Got it off - turns out there were still a couple of head bolts in. I blame the world's worst shop dog, who wouldn't leave me alone until I chased her around the garage for a while.

The other cylinders look like the one I posted a picture of. I don't see any damage. No cross hatching either though.

Now that I've got it apart this far, I feel the terrible urge to keep going. Those heads are so heavy, putting the weight back on the car makes me feel dirty. I'm going to have to think this over for a while.
 
I'm digging through my parts finding what I want to sell and what are keepers for the Roadrunner. That includes a lot of small block parts, mostly NOS and older performance parts. If you have a list of things you're looking for let me know and I'll keep an eye out for them.

Thanks,
Jim
 
I'll keep it in mind. Right now I'm wondering if it is worth tearing the motor down further. The factory bottom end is supposed to be pretty stout, isn't it? I'm a little concerned about the piston rings, although there was no sign of them being bad twenty years ago. But so far everything looks good, except for being carboned up or caked with old dried oil.

The transmission was rebuilt around 96 and only has a few thousand miles on it. I'm assuming the rear main seal would have been replaced when the transmission was rebuilt, so the rear main seal is "only" 28 years old and lightly used. I've got no idea what that seal is like, do they dry rot?

I've seen an opinion that transmissions tend to go after sitting this long, which was rough to hear since my rebuild has so few miles on it. Maybe I should wait on the rear main seal until I see how the transmission does?

Are there any other seals in the short block I need to worry about?
 
Question about power, I'm seeing 230 hp/340 tq for early 318's and 150ish HP/260 tq somewhere in the 70's. Which one will my 72 have? I'm guessing the latter but I don't have any smog control stuff, so I don't know why the power would be down.
 
Cylinders have a noticeable ridge at the top. I saw Lunar Outlaw on YouTube check for it, and it sounds like a bad thing, and that's as much as I know about it so far.
 
Question about power, I'm seeing 230 hp/340 tq for early 318's and 150ish HP/260 tq somewhere in the 70's. Which one will my 72 have? I'm guessing the latter but I don't have any smog control stuff, so I don't know why the power would be down.
the test methods for rating engine power and torque changed in 1972 and the ratings dropped.
They also dropped as compressio ratio and "smog era" controls were added.
It really comes down to how far down the piston is in the hole.
Everything above that can easily be changed and/or replaced for better performance fairly easily.
 
If you have a smog era Teen and want to bump the compression you can use closed chamber heads. 273 heads before 68 are closed chamber and have the same port sizes as the 318 heads. The aluminum heads are closed chamber as well. You will get around a halp point increase by switching from open to closed chamber but
(But) the original head gaskets were steel shim and very thin. Those gaskets aren't available any more so you need to use the thinnest composite gasket or MLS gasket you can find. Mr Gasket #1121G is a .028 thickness composite and Cometic has a #C5633-027 that is a MLS (multilayer steel) gasket that is .027 compressed thickness. THat's about as thin as you can get. The best way to build compression is with pistons. Zero deck with a closed chamber work well and will get you up to 9.5/1 or better with the correct head gasket.
 
So, how bad is this ridge at the top of the cylinder? It seems like that would be a problem if switching to a piston that is higher in the hole, or zero deck.

Anyway, bear with me if there is not immediate progress on this. I'm trying to get parts back on the car so I have room to work on the engine.
 
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