351 engine tear down

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73 Ford Mustang Mach 1 351 CJ all matching numbers, under restoration.
73 Ford Mustang Sprint from Mexico.
Today I started to look at the next step, which is the rings cut. On the original pistons, the first ring is marked with a dot for the assembly.
I looked at the new rings, with +0.030" because the block has been re-bored, and the mark is on the compression ring. There is no mark on the first ring, how come?

I come back to the cut, if I have the right information, as the block has been re-bored to +0.030", I must file the rings:
0.004 x 4.030 = 0.016"

Do I have to file all the rings as well including the wipers?
I need to get a fine file for this.
 

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Last edited:
Joined
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1972 Mach 1
1971 Ranchero
There should have been some instructions with your rings. That's a good place to start. Marks generally indicate which side goes up. No mark usually means it doesn't matter. It has to do with the ring's cross section and position (top, 2nd). You want to check the gap on all of the rings (including oil control wipers). The gap will differ depending of piston material, application, and "power adders" (turbo, supercharger, nitrous). In general, the 2nd ring should have slightly more gap than the top. This has to do with not trapping pressure between the rings.
 
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1971 M-Code Mach 1 w/408C stroker
At the rate I'm going, the engine should be reassembled within a decade, by which time we'll be running on what, hydrogen?
Well, the crankshaft is fitted, I've coated the journals well with Red Lube, and won't forget to put Permatex Supra Black on the rear bearing to prevent any oil leaks. A little progress next week, if I think about it, if I have time, if I want to...
Keep at it. Rome was not built in one day.;)
 
Joined
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73 Ford Mustang Mach 1 351 CJ all matching numbers, under restoration.
73 Ford Mustang Sprint from Mexico.
Well, I just have to file, it's a patient game. I did a test on the first ring that will go to cylinder number 1, I have to go slowly, I almost exceeded the maximum tolerance.

Rome is a beautiful city, we know why :)
 

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Paul M

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73 loaded Q code car w/a 351 4v C6 it came with 2 cars in parts.
Experimentation I would say as I never been so far in a restoration.

A lot of crap wason the heads, and under the pan valley, surely caused by a very poor maintenance. When I opened the engine last evening, the smell remind me some location with H2S, but no I was not on a job.

I have a few push rods bented.

Any suggestions are welcome, I need to refer to books and documentation I have to continue the job, and of course the help of this site ::thumb::

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Yep soak the distributer, then work it back n forth. The lifters are prob. slightly mushroomed, I switched from a lifter puller to vice grips on mine & tossed 'em. Cam, lifters, bearings, pistons, timing chain n gears are junk. You'll end up going .030 on the bore. No domed pistons for your build. A good quality forged flat top will bump up your comp a bit. I went with these pro tru street pistons from Wlseco. at 500 they're the best bang for the buck. Don't be surprised to get your big end resized on your rods, the guides may be worn (don't bother knurling, it's a temp fix) If your oil pan is baffled to match that pick up it's a Cobra jet pan. These are expensive motors to build, invest some $ in it and you'll be happy. My Cleveland cost me more money to build than my 440 Mopar. Don't be surprised to wait for parts longer than usual. You may want to make sure they have them in stock.
 

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Joined
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My all time favorite vehicle is our 1969 Shelby GT500
There should have been some instructions with your rings. That's a good place to start. Marks generally indicate which side goes up. No mark usually means it doesn't matter. It has to do with the ring's cross section and position (top, 2nd). You want to check the gap on all of the rings (including oil control wipers). The gap will differ depending of piston material, application, and "power adders" (turbo, supercharger, nitrous). In general, the 2nd ring should have slightly more gap than the top. This has to do with not trapping pressure between the rings.
I am certain the maker of the tings wants you do install and break the new rings in properly. I would reach out to them and get directions from them.
 

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