bluefury361
Old Man with a Hat
Can't wait to see that baby cleaned up.
New to me 78 NYB on its way but please Don't tell my wife
- Thread starter 73 T&C
- Start date
Pulled the engine to give it a good look see...
And what I found wasn’t pretty.
towed her in because the oil pressure warning light went off. Oil level and movement of oil at the top looked fine but still... just in case. Oil pressure sender turned out to be bad.
Chipped piston head... interesting but not immediately fatal.
As suspected from the head coolant leak on the outside, the head gasket was toast. Engine looks like it was overheated badly too .... and some devils brew of head sealer may have been used judging by the looks of things.
Looks like rebuild time has come. With only 106k miles a little too soon. Will check bearings and cylinders next. But it’s only out of forensic curiosity. Strip, hot dip, machine and rebuild here we come. Yay!!!!! Finally. A good base to have to keep her and will live up to the excellent body of car. More pictures to follow of the engine ****.....
ps.... yes, that’s my wagon in the background.... in for some rust repairs. Gas tank out and flushed... due to some nearby welding....it was pretty clean. Almost done. I don’t usually have two cars “under the knife” at the same time but this couldn’t be helped.
And what I found wasn’t pretty.
towed her in because the oil pressure warning light went off. Oil level and movement of oil at the top looked fine but still... just in case. Oil pressure sender turned out to be bad.
Chipped piston head... interesting but not immediately fatal.
As suspected from the head coolant leak on the outside, the head gasket was toast. Engine looks like it was overheated badly too .... and some devils brew of head sealer may have been used judging by the looks of things.
Looks like rebuild time has come. With only 106k miles a little too soon. Will check bearings and cylinders next. But it’s only out of forensic curiosity. Strip, hot dip, machine and rebuild here we come. Yay!!!!! Finally. A good base to have to keep her and will live up to the excellent body of car. More pictures to follow of the engine ****.....
ps.... yes, that’s my wagon in the background.... in for some rust repairs. Gas tank out and flushed... due to some nearby welding....it was pretty clean. Almost done. I don’t usually have two cars “under the knife” at the same time but this couldn’t be helped.
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FarCanal
Member
Uh Huh ..... So they don't have "Depressed'' Pistons (although that one does look a little sad) lol
SO ..... Gentlemen ..... WHERE did all the Compression go from the High Hp, Torque Monsters of the Muscle Car era ??? Huge cc'd heads or what ???
Please reply
Cheers, Big Jim from DownUnder
P.S. As I just purchased a "Built" Motor, from an engine builder who lost his business in the US = See pic ..... Imported it and put that in !
SO ..... Gentlemen ..... WHERE did all the Compression go from the High Hp, Torque Monsters of the Muscle Car era ??? Huge cc'd heads or what ???
Please reply
Cheers, Big Jim from DownUnder
P.S. As I just purchased a "Built" Motor, from an engine builder who lost his business in the US = See pic ..... Imported it and put that in !
Looks like we were getting coolant in the engine too. This must have been a recent development as I had just changed the oil not long before and there wasn’t any evidence of water in the oil.
commando1
Old Man with a Hat
Damn, that is one worn engine. Previous owner(s) obviously did their engine maintenance and repairs at AutoZone.
Get some Keith Black Hyper-whaterthefukyoucallit Domed pistons with valve reliefs and that will put you right at 10.1:1 CR.
Get some Keith Black Hyper-whaterthefukyoucallit Domed pistons with valve reliefs and that will put you right at 10.1:1 CR.
Thinking about that right now. Higher lift cam??? Or should I just stay all stock? Would love a little more oomph but not looking to beat everyone on the quarter mile.
want it to be smooth not lumpy.
want it to be smooth not lumpy.
commando1
Old Man with a Hat
I don't know if it's still available but the Purple Cam has the same specs as the 1969 440 HP (375/385hp).
I found a NOS 440 HP cam and I loved it.
More engine ****....
Original cam sprocket with nylon cover. Intact at over 110k miles but still going in the trash. Timing chain had at least 1/2” of play as well.
Table o parts. Heads off to the machine shop for new valve seats, guides and machine work.
That is a big heavy block. Being stripped for the hot tank and then just going to hone it. Less than 1 mil wear in the cylinders and almost negligible ridge at the top. Surprising. You can still se traces of the original honing. Just for kicks, I pulled a rod cap to measure the bearing wear. Plastiguaged it and found the clearance to be 15 thousandths. .0015. Really not too bad at all. Bottom bearings still god with only the lightest wear but I’m changing them all regardless. New bearing caps will be enough. Crank.... I’ll just polish a bit.
Turns out those weren’t chips on the piston crown... just the orienting marks. Only one piston had it that I could see initially. When I decarboned the rest, there they all were.
Original cam sprocket with nylon cover. Intact at over 110k miles but still going in the trash. Timing chain had at least 1/2” of play as well.
Table o parts. Heads off to the machine shop for new valve seats, guides and machine work.
That is a big heavy block. Being stripped for the hot tank and then just going to hone it. Less than 1 mil wear in the cylinders and almost negligible ridge at the top. Surprising. You can still se traces of the original honing. Just for kicks, I pulled a rod cap to measure the bearing wear. Plastiguaged it and found the clearance to be 15 thousandths. .0015. Really not too bad at all. Bottom bearings still god with only the lightest wear but I’m changing them all regardless. New bearing caps will be enough. Crank.... I’ll just polish a bit.
Turns out those weren’t chips on the piston crown... just the orienting marks. Only one piston had it that I could see initially. When I decarboned the rest, there they all were.
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commando1
Old Man with a Hat
Nothing like keeping all the parts sorted, bagged, and tagged... 
Jav, you missed a great lunch at Tattoos and Pie yesterday. Jeff picked up the tab..
Jav, you missed a great lunch at Tattoos and Pie yesterday. Jeff picked up the tab..
More.....
Same table different view
Lonely engine bay.... changing out power steering hoses, major hoses and redoing radiator again because... already hear.
Same table different view
Lonely engine bay.... changing out power steering hoses, major hoses and redoing radiator again because... already hear.
Nothing like keeping all the parts sorted, bagged, and tagged...
Jav, you missed a great lunch at Tattoos and Pie yesterday. Jeff picked up the tab..
damn! Would have brought the 73 RoadRunner.... it was my in between covid project to get her fully commissioned after a two year hiatus. New limited slip rear end and some minor body work. Just repaired the ammeter on her and rehabbed the full rally dash gauge package.... she came out sweet too!
Rally guages all cleaned and the lenses polished. Note new decal on (fully manual) A/C controls.... looks killer new.
Install was slow and steady. The cause was not. Intermittent short from the ammeter and loose fusible link were working together to drive me crazy with weird cut out of the ignition system. When I found the fusible link fault and fixed it... it immediately fused the short in the dash and burned up... thereby doing it’s job. Had to run down the short with my power probe tester (if you don’t have one you need one) fixing little problems along the way like sorting a lot of loose connectors and replacing the main power lead to the fuse panel with a new red 10ga wire.
Found the fault at the ammeter and brazed the studs on to it following some advice I got on the B body sister site. Alternator was also week so I went with a 90 amp unit because.... This is America damn it!
Now she runs sweet, charges right up after start and no amount of accessories perturb the system or dim the lights at idle.
Dash in and lit up... yes I changed all the bulbs.
New stripe kit with the touch up paint work on the fenders, trunk and rear window.
Clean engine bay for a driver ... All my cars a drivers.
Cool new alternator from PowerMaster.
Yeah... I know.. it’s chrome. Place needed a little bling.
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Just ordered purple shaft and new hydraulic lifter kit from summit.272/272 with almost .5 inch lift at the valve. Limited overlap should help keep vacuum up. Let’s see how she moves with that one in her gut.
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commando1
Old Man with a Hat
Mr C
Senior Member
The compression went away because the smog era engine pistons at the top of travel still sit down in the block. The heads and everything else are still great pieces. The secret to waking up a Mopar smogger is to replace the pistons (as mentioned already) and get the compression back up.
Your question was about CR, but power was also down also due to smogger cam grinds too.
70bigblockdodge
Old Man with a Hat
Those are non OEM head gaskets. Big block Chrysler all had steel shim gaskets. Those look like old Victor or Mr gasket, head gaskets.
Sunday thinking ....... bumping up the pistons.
need to do some math to see what the CR would be.
need to do some math to see what the CR would be.
70bigblockdodge
Old Man with a Hat
Summit has a great calculator. Look up a piston for your engine and the calculator will show up at the bottom. Plug in numbers to see where you are, or where you would like to be.
Here is zero deck, flat top, with no valve reliefs. I would not go that high with such a small cam, but it gives you a idea.
Here is zero deck, flat top, with no valve reliefs. I would not go that high with such a small cam, but it gives you a idea.
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78Brougham
"Chump"
Your Road Runner looks awesome!
But those titties really need to go.
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