Are these cracks??
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Instructor
Joined: Feb 2021
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I had something happen once while driving normally at highway speeds. I was near a Corvette shop so I limped there and left the car with them. Since I never really saw what they saw, I have to guess as to what happened. I think I let the lash on my solid lifter cam get too loose and for a brief moment the valve hit the piston. I did not have damage to the head nor to the piston and I drove it for some time afterwards without apparent problems. However, when I pulled the engine for a rebuild, I discovered the incident had bent the connecting rod fairly significantly. I mention this on;y to suggest that if no further work is required to the rotating parts, and you still have the head off, rotate the crank and double check that all four pistons in that bank achieve an equal top of stroke height. A bent connecting rod will leave the piston deeper in the hole and you'll lose compression in that cylinder. I did and never knew it.
At this point, I would pull the other head as well! I'd have that one checked and cleaned too....what kind of valve seals do you have? I'd make sure they all get get some good positive-lock seals installed if not already. The majority of the disassembly is done, I'd check both heads and clean all of the piston tops! Something to consider👍
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From: SW Florida.
valves too loose will not make a valve hit the piston. and there would be a clear mark in the valve relief where it did hit. and on the edge of the valve. if you have compression, fuel and timing anywhere close and it will pop. will even pop 180 degrees out. pop thru carb, but it will pop. HEI? buy a 30 buck ebay distributor. start it. then swap parts in yours until it runs.. then buy that part. module, pickup coil, whatever and have a whole spare distributor. try yours one more time with starting fluid after reassembly. timing light? does it flash while cranking? hand your wile a plug wire. crank it. does she get really mad at you? you have spark...
Thread Starter
Instructor
Joined: Feb 2021
Posts: 144
Likes: 17
valves too loose will not make a valve hit the piston. and there would be a clear mark in the valve relief where it did hit. and on the edge of the valve. if you have compression, fuel and timing anywhere close and it will pop. will even pop 180 degrees out. pop thru carb, but it will pop. HEI? buy a 30 buck ebay distributor. start it. then swap parts in yours until it runs.. then buy that part. module, pickup coil, whatever and have a whole spare distributor. try yours one more time with starting fluid after reassembly. timing light? does it flash while cranking? hand your wile a plug wire. crank it. does she get really mad at you? you have spark...
Race Director
Joined: Jul 2015
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From: SW Florida.
so, you snapped #8 connecting rod. anything can be repaired. we don't know anything about the block. numbers matching to the car and special? it is a 4 bolt. but a lot are. if the numbers natch, put it in the corner and decide later. if not get 10 cents a pound for it. now, go find a 96-02 chevy express van that popped the intake gasket and take that 4 bolt roller vortec block and start over. you may be able to re-ring it and go. my 01 gmc savana had a gallon of water in the pan when i bought it. put heads on it and have done 2 round trips from jersey to florida so far. you give GM engineers 40 years to improve an engine and they are gonna improve that engine... where is home for you? i am good at finding stuff.
Is my vette stock?? HAHA
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clean off the oil and take it to a machine shop and have it magnafluxed. If its severely cracked junk it or have it sleeved. THat area is below the rings so its not critical area. The machinist will give you an educated answer to different possibilities, not a bunch of keyboard hacks saying this or that. The only legitimate reason to save a severely cracked block is if its a rare big block or its a numbers matching block
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,155
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
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the rings are well above that chip unless there is a crack that runs up the cylinder bore
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Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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Race Director
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From: SW Florida.
new block? or better used block? boring it to these .030 pistons? or starting over with new stuff? did that rod break? if so, you need a crank too. so you may want to consider a fully balanced rotating assy. and in that case, 383 may make more sense...
Thread Starter
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Also no rods were broke. All the bearings were ate up though.
Race Director
Joined: Jul 2015
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From: SW Florida.
then what ate that lower corner of the #8 cylinder? and 383-388. balance is usually external. so a flywheel and balancer will need to be matched to the rotating assy. unless it will be neutral balanced. 6 inch rods should be looked into, but a bit harder with longer stroke. but also more needed with longer stroke. and now your inadequate stock heads just became more inadequate.
Thread Starter
Instructor
Joined: Feb 2021
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then what ate that lower corner of the #8 cylinder? and 383-388. balance is usually external. so a flywheel and balancer will need to be matched to the rotating assy. unless it will be neutral balanced. 6 inch rods should be looked into, but a bit harder with longer stroke. but also more needed with longer stroke. and now your inadequate stock heads just became more inadequate.