Rebuilding fathers Corvette. Engine Lunged... questions!
12-09-2013, 05:17 PM
#1
Advanced
Thread Starter
Rebuilding fathers Corvette. Engine Lunged... questions!
Hey everyone,
I posted over in general about getting my fathers 1968 Chevy Corvette up and going again. Lots of great response there, thanks guys. A lot of it was over my head as far as technical comprehension goes but... everything changed up.
One thing that was a sticky point with the engine is not knowing what was done to it. My father had one story of the engine, and the dyno told a different story. So, I decided to have the shop that did the dyno tuning for me pull one head,get measurements of everything so we'd know exactly what we're dealing with.
During the initial work they did on the engine for me before the dyno, I had them do a compression check on the engine. We had pretty good numbers all around (210psi) but one cylinder was "low" at 194 PSI. I had them pull the head from that side incase it was a gasket leak or something and when bolting it all together we resoled the issue.
Unfortunately, the issue was much larger. The end gap of the rings wasn't proper when the engine was assembled, and it crunched together and blew a chunk of the piston off, or so they suspects. It's honestly splitting hairs determining the issue though since when I pulled the plugs on the corvette two of them had the ceramic blown out... so who knows the specifics but the piston walls are scarred to all hell and I'm amazed it ran at all. It probably wasn't far from failing miserably.
So here's my situation and I really appreciate your help:
A new engine is required it would appear. Redoing the current engine would be a chore that I'm not prepare for space wise, time wise, skill wise, or tool wise.
My father had two extra engines laying around the garage to go with the Corvette. I'm thinking this may be a good idea...
One engine, is the original but NOT number matching 327 engine. My father bought the Corvette wrecked and got a new frame for it. Supposedly this engine has under 10k miles on it, so it should be in bearable shape. It hasn't turned over for as long as I am capable of remember of, so 25 years or so at LEAST since it's spun a single rotation.
The other engine is unknown in size or anything, but my father got from a junkyard from a blazer I believe he was saying and he thought it would bolt right up. Unknown size or specs or anything. He was intending to replace the current engine with this so he could get off of having to using an engine requiring race gas (the current lunged engine in the corvette).
What would you do in this situation?
Things to know to be in my shoes:
-You've got $3k.
-You only have limited time on weekends because you're still helping your mom prep the property for sale in your father passing., maybe 6-10 hours a weekend.
-You've got one friend with engine knowledge and availability in the whole state for help.
-You've only ever worked on Motorcycle engines. You've torn apart countless carbs on 4 cylinder sport bikes and dyno tuned a few bikes. You've redone pistons on single cylinder dirt bikes... but you've never split the cases on a bike and you've not done very much with cars at all.
My idea:
Take the 327. It's nothing special it would seem since it's not number matching. Check compression, hopefully get good results. Pull heads to replace with nicer aftermarket ones ($600?) and inspect pistons and walls while at it. If it all checks out proceed. Slap the brand new holley 650 CFM quad barrel double pump carb on the new intake manifold. Bolt up old exhaust since it should all still work.
Hopefully be able to do it all for under 3 grand, including beer and pizza for my good friend to help me out.
What do you guys think?
I posted over in general about getting my fathers 1968 Chevy Corvette up and going again. Lots of great response there, thanks guys. A lot of it was over my head as far as technical comprehension goes but... everything changed up.
One thing that was a sticky point with the engine is not knowing what was done to it. My father had one story of the engine, and the dyno told a different story. So, I decided to have the shop that did the dyno tuning for me pull one head,get measurements of everything so we'd know exactly what we're dealing with.
During the initial work they did on the engine for me before the dyno, I had them do a compression check on the engine. We had pretty good numbers all around (210psi) but one cylinder was "low" at 194 PSI. I had them pull the head from that side incase it was a gasket leak or something and when bolting it all together we resoled the issue.
Unfortunately, the issue was much larger. The end gap of the rings wasn't proper when the engine was assembled, and it crunched together and blew a chunk of the piston off, or so they suspects. It's honestly splitting hairs determining the issue though since when I pulled the plugs on the corvette two of them had the ceramic blown out... so who knows the specifics but the piston walls are scarred to all hell and I'm amazed it ran at all. It probably wasn't far from failing miserably.
So here's my situation and I really appreciate your help:
A new engine is required it would appear. Redoing the current engine would be a chore that I'm not prepare for space wise, time wise, skill wise, or tool wise.
My father had two extra engines laying around the garage to go with the Corvette. I'm thinking this may be a good idea...
One engine, is the original but NOT number matching 327 engine. My father bought the Corvette wrecked and got a new frame for it. Supposedly this engine has under 10k miles on it, so it should be in bearable shape. It hasn't turned over for as long as I am capable of remember of, so 25 years or so at LEAST since it's spun a single rotation.
The other engine is unknown in size or anything, but my father got from a junkyard from a blazer I believe he was saying and he thought it would bolt right up. Unknown size or specs or anything. He was intending to replace the current engine with this so he could get off of having to using an engine requiring race gas (the current lunged engine in the corvette).
What would you do in this situation?
Things to know to be in my shoes:
-You've got $3k.
-You only have limited time on weekends because you're still helping your mom prep the property for sale in your father passing., maybe 6-10 hours a weekend.
-You've got one friend with engine knowledge and availability in the whole state for help.
-You've only ever worked on Motorcycle engines. You've torn apart countless carbs on 4 cylinder sport bikes and dyno tuned a few bikes. You've redone pistons on single cylinder dirt bikes... but you've never split the cases on a bike and you've not done very much with cars at all.
My idea:
Take the 327. It's nothing special it would seem since it's not number matching. Check compression, hopefully get good results. Pull heads to replace with nicer aftermarket ones ($600?) and inspect pistons and walls while at it. If it all checks out proceed. Slap the brand new holley 650 CFM quad barrel double pump carb on the new intake manifold. Bolt up old exhaust since it should all still work.
Hopefully be able to do it all for under 3 grand, including beer and pizza for my good friend to help me out.
What do you guys think?
Last edited by shredjesse; 12-09-2013 at 05:22 PM.
12-09-2013, 06:07 PM
#2
Le Mans Master
Hey everyone,
I posted over in general about getting my fathers 1968 Chevy Corvette up and going again. Lots of great response there, thanks guys. A lot of it was over my head as far as technical comprehension goes but... everything changed up.
One thing that was a sticky point with the engine is not knowing what was done to it. My father had one story of the engine, and the dyno told a different story. So, I decided to have the shop that did the dyno tuning for me pull one head,get measurements of everything so we'd know exactly what we're dealing with.
During the initial work they did on the engine for me before the dyno, I had them do a compression check on the engine. We had pretty good numbers all around (210psi) but one cylinder was "low" at 194 PSI. I had them pull the head from that side incase it was a gasket leak or something and when bolting it all together we resoled the issue.
Unfortunately, the issue was much larger. The end gap of the rings wasn't proper when the engine was assembled, and it crunched together and blew a chunk of the piston off, or so they suspects. It's honestly splitting hairs determining the issue though since when I pulled the plugs on the corvette two of them had the ceramic blown out... so who knows the specifics but the piston walls are scarred to all hell and I'm amazed it ran at all. It probably wasn't far from failing miserably.
So here's my situation and I really appreciate your help:
A new engine is required it would appear. Redoing the current engine would be a chore that I'm not prepare for space wise, time wise, skill wise, or tool wise.
My father had two extra engines laying around the garage to go with the Corvette. I'm thinking this may be a good idea...
One engine, is the original but NOT number matching 327 engine. My father bought the Corvette wrecked and got a new frame for it. Supposedly this engine has under 10k miles on it, so it should be in bearable shape. It hasn't turned over for as long as I am capable of remember of, so 25 years or so at LEAST since it's spun a single rotation.
The other engine is unknown in size or anything, but my father got from a junkyard from a blazer I believe he was saying and he thought it would bolt right up. Unknown size or specs or anything. He was intending to replace the current engine with this so he could get off of having to using an engine requiring race gas (the current lunged engine in the corvette).
What would you do in this situation?
Things to know to be in my shoes:
-You've got $3k.
-You only have limited time on weekends because you're still helping your mom prep the property for sale in your father passing., maybe 6-10 hours a weekend.
-You've got one friend with engine knowledge and availability in the whole state for help.
-You've only ever worked on Motorcycle engines. You've torn apart countless carbs on 4 cylinder sport bikes and dyno tuned a few bikes. You've redone pistons on single cylinder dirt bikes... but you've never split the cases on a bike and you've not done very much with cars at all.
My idea:
Take the 327. It's nothing special it would seem since it's not number matching. Check compression, hopefully get good results. Pull heads to replace with nicer aftermarket ones ($600?) and inspect pistons and walls while at it. If it all checks out proceed. Slap the brand new holley 650 CFM quad barrel double pump carb on the new intake manifold. Bolt up old exhaust since it should all still work.
Hopefully be able to do it all for under 3 grand, including beer and pizza for my good friend to help me out.
What do you guys think?
I posted over in general about getting my fathers 1968 Chevy Corvette up and going again. Lots of great response there, thanks guys. A lot of it was over my head as far as technical comprehension goes but... everything changed up.
One thing that was a sticky point with the engine is not knowing what was done to it. My father had one story of the engine, and the dyno told a different story. So, I decided to have the shop that did the dyno tuning for me pull one head,get measurements of everything so we'd know exactly what we're dealing with.
During the initial work they did on the engine for me before the dyno, I had them do a compression check on the engine. We had pretty good numbers all around (210psi) but one cylinder was "low" at 194 PSI. I had them pull the head from that side incase it was a gasket leak or something and when bolting it all together we resoled the issue.
Unfortunately, the issue was much larger. The end gap of the rings wasn't proper when the engine was assembled, and it crunched together and blew a chunk of the piston off, or so they suspects. It's honestly splitting hairs determining the issue though since when I pulled the plugs on the corvette two of them had the ceramic blown out... so who knows the specifics but the piston walls are scarred to all hell and I'm amazed it ran at all. It probably wasn't far from failing miserably.
So here's my situation and I really appreciate your help:
A new engine is required it would appear. Redoing the current engine would be a chore that I'm not prepare for space wise, time wise, skill wise, or tool wise.
My father had two extra engines laying around the garage to go with the Corvette. I'm thinking this may be a good idea...
One engine, is the original but NOT number matching 327 engine. My father bought the Corvette wrecked and got a new frame for it. Supposedly this engine has under 10k miles on it, so it should be in bearable shape. It hasn't turned over for as long as I am capable of remember of, so 25 years or so at LEAST since it's spun a single rotation.
The other engine is unknown in size or anything, but my father got from a junkyard from a blazer I believe he was saying and he thought it would bolt right up. Unknown size or specs or anything. He was intending to replace the current engine with this so he could get off of having to using an engine requiring race gas (the current lunged engine in the corvette).
What would you do in this situation?
Things to know to be in my shoes:
-You've got $3k.
-You only have limited time on weekends because you're still helping your mom prep the property for sale in your father passing., maybe 6-10 hours a weekend.
-You've got one friend with engine knowledge and availability in the whole state for help.
-You've only ever worked on Motorcycle engines. You've torn apart countless carbs on 4 cylinder sport bikes and dyno tuned a few bikes. You've redone pistons on single cylinder dirt bikes... but you've never split the cases on a bike and you've not done very much with cars at all.
My idea:
Take the 327. It's nothing special it would seem since it's not number matching. Check compression, hopefully get good results. Pull heads to replace with nicer aftermarket ones ($600?) and inspect pistons and walls while at it. If it all checks out proceed. Slap the brand new holley 650 CFM quad barrel double pump carb on the new intake manifold. Bolt up old exhaust since it should all still work.
Hopefully be able to do it all for under 3 grand, including beer and pizza for my good friend to help me out.
What do you guys think?
Please keep us posted.
12-09-2013, 06:13 PM
#3
Team Owner
Member Since: Oct 2004
Location: altered state
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St. Jude Donor '05
Id pull heads and make sure the bores arent rusted/rings stuck
Pull the pan check bearings. One at a time its not difficult at all. Then order parts as needed. Bet it costs you a few hundred (under $500) if it needed a quick ball hone, rings bearings gaskets basics.
Or,
If the motor turns over Ok by hand go to Oreillys spend $30 on a cheap borescope. Stick it down the spark plug hole and you can see inside the cyl that way also.
Replacing valve springs/seals wouldnt be a bad idea they are cheap.
If you really wanted it nice 3k is plenty to have a shop do a basic rebuild, upgrade a cam/springs maybe even a little bowl work and have money left over.
Pull the pan check bearings. One at a time its not difficult at all. Then order parts as needed. Bet it costs you a few hundred (under $500) if it needed a quick ball hone, rings bearings gaskets basics.
Or,
If the motor turns over Ok by hand go to Oreillys spend $30 on a cheap borescope. Stick it down the spark plug hole and you can see inside the cyl that way also.
Replacing valve springs/seals wouldnt be a bad idea they are cheap.
If you really wanted it nice 3k is plenty to have a shop do a basic rebuild, upgrade a cam/springs maybe even a little bowl work and have money left over.
Last edited by cv67; 12-09-2013 at 06:15 PM.
12-09-2013, 06:27 PM
#5
Advanced
Thread Starter
I'll try and give you a ring Richard. I'm not off most days until after 7pm or so though (EST) so I doubt you'd be around?
So with the 327:
First, pull the plugs and try and turn it over by hand... if it goes, proceed to check the bore for... rust? Knicks/damage? Not entirely sure what I am looking for. I imagine it's worth just digging into the puppy and pulling the heads, since it's not worth much if the bore is munged anyways, and I imagine there's a decent amount of power to unlock in this puppy by going with different heads?
So with the 327:
First, pull the plugs and try and turn it over by hand... if it goes, proceed to check the bore for... rust? Knicks/damage? Not entirely sure what I am looking for. I imagine it's worth just digging into the puppy and pulling the heads, since it's not worth much if the bore is munged anyways, and I imagine there's a decent amount of power to unlock in this puppy by going with different heads?
12-09-2013, 09:51 PM
#6
Drifting
I suggest deciding what you want to do with the car and go from there. I have spent tons of money kinda aimlessly. These cars are money pits; spend your hard earned cash wisely. Whether it's the 327 or 350, make sure it is ready and done right.
12-09-2013, 10:27 PM
#7
Le Mans Master
At a $3K budget you could do a very simple but quality overhaul of the 327 and be *sure* it's a good engine. No major upgrades - just a good performance overhaul making about 325 HP or so. Unless something is broken, you should easily be able to make that number if you're smart and careful. I wouldn't spend any money on new heads or other stuff at this point or trust me - your budget will go right out the window.
Some casting numbers here would be good - block and heads.
Some casting numbers here would be good - block and heads.
12-09-2013, 10:56 PM
#8
Advanced
Thread Starter
I'd like to see around 325hp on the thing and a good street able amount of power. I don't want it doggy, and at 250hp on the dyno to the rear wheel it was just a bit lack luster... but I'm spoiled by my last GSXR 750 track bike that was 136hp on the dyno and 400lbs!
So it sounds like this would be a good weekend plan to do and then report back:
1- Pull spark plugs, see if engine turns over.
2- If it turns over, pull intake manifold and heads, inspect cylinder
3- Come back with casting numbers. Just incase come back with casting numbers on both engines.
Seem sensible enough?
I'd be willing to up the budget to $4k if new headers would make a difference. Reviewing the cost of good headers it seems like $650-900 a set for complete headers does the trick. This combination of vortec iron headers and intake manifold has also been highly advised to me:
https://sdparts.com/details/scoggin-...nter/sd8060kit
So it sounds like this would be a good weekend plan to do and then report back:
1- Pull spark plugs, see if engine turns over.
2- If it turns over, pull intake manifold and heads, inspect cylinder
3- Come back with casting numbers. Just incase come back with casting numbers on both engines.
Seem sensible enough?
I'd be willing to up the budget to $4k if new headers would make a difference. Reviewing the cost of good headers it seems like $650-900 a set for complete headers does the trick. This combination of vortec iron headers and intake manifold has also been highly advised to me:
https://sdparts.com/details/scoggin-...nter/sd8060kit
Last edited by shredjesse; 12-09-2013 at 11:00 PM.
12-10-2013, 07:47 AM
#9
Take the 4k, sell all three old engines for the most you can get for them. Put all the money together and buy a decent crate engine from a forum vendor and you are good to go. Reliable, warrantee, drivable, easy and clean. That would solve all the questions of what you really have and be ultimately drivable, what your father would have liked probably.
12-10-2013, 09:07 AM
#10
Drifting
Take the 4k, sell all three old engines for the most you can get for them. Put all the money together and buy a decent crate engine from a forum vendor and you are good to go. Reliable, warrantee, drivable, easy and clean. That would solve all the questions of what you really have and be ultimately drivable, what your father would have liked probably.
I like that idea the best.
12-10-2013, 09:44 AM
#12
Melting Slicks
Before I spent any money, I would check out the spare 327. Pull the plugs and spray a good amount of WD40 or Marvel Mystery Oil in each cylinder and let it sit for a few days. This will help loosen any rust and hopefully free up the rings. Then, with the plugs still out, try to turn the crankshaft using a big bolt in the snout and a suitable wrench. It will take some effort. If it is still stuck, repeat the oil and sitting process as before. Then try again. Hopefully it will break free and turn with the wrench. Once past that, turn the engine over and remove the pan. Note the two bolts at the front at either side of the front cover. Remove each bearing cap in order and check the bearings. Hopefully they are not worn into the base metal (probably brass) or badly scored. If they check out, apply some assembly lube from your favorite auto parts store and reassemble. Torque each as required. The rear cap will have a seal which I would replace now. Replace the pan with a fresh gasket, put a new filer on it, and turn the engine upright. Replace anything you had to remove or that the engine needs at this point. Be sure to prime the oil pump with a drill and primer tool to get lubricant to the bearings and lifters. I would hazard a guess that it will be ready to run at this point after it is reassembled and installed in the car. If not, you are out very little money plus whatever time it took.
12-10-2013, 10:20 AM
#13
Advanced
Thread Starter
That also sounds good to me. Any idea what bolt to go with so I can hit a hardware store and get the correct one?
I'm not entirely sure what I'm looking at for bearing wear, or what the snout is, or even what bearings you're referencing. Any chance you could toss me a few pictures?
Should I be concerned about the valves being stuck open or closed having sat for so long?
I'm not entirely sure what I'm looking at for bearing wear, or what the snout is, or even what bearings you're referencing. Any chance you could toss me a few pictures?
Should I be concerned about the valves being stuck open or closed having sat for so long?
12-10-2013, 11:27 AM
#14
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St. Jude Donor '05
The valvesprings are probably real weak which can kill power and reliability..they are cheap though the valve seals for sure are dried out. again cheap and easy to replace.
Stick a few long bolts in the balancer thread them in about an inch then stick a long bar screwdriver etc through them should be able to turn it over once the plugs are out. Or try it by the rear of the crank if the balancer doesnt use a center bolt
Stick a few long bolts in the balancer thread them in about an inch then stick a long bar screwdriver etc through them should be able to turn it over once the plugs are out. Or try it by the rear of the crank if the balancer doesnt use a center bolt
12-10-2013, 11:34 AM
#15
Advanced
Thread Starter
Interesting.
Would it be worth doing a compression test if the valve springs are weak and the seals are dried out, or would it not tell me anything?
This is where it seems worth while to me from a time and having some money perspective to slap on new heads, especially since it will help generate additional power output anyways.
I'll see about getting it to turn over and I'll check the bearings as best as i can tell and post pictures!
Would it be worth doing a compression test if the valve springs are weak and the seals are dried out, or would it not tell me anything?
This is where it seems worth while to me from a time and having some money perspective to slap on new heads, especially since it will help generate additional power output anyways.
I'll see about getting it to turn over and I'll check the bearings as best as i can tell and post pictures!