great job John. Your video's are very informative and helpful. Your attention to detail is wonderful. I'm guessing your day job is in engineering. I have a 1969 roadster that I did a body off on 26 years ago and I wish I had UA-cam back then. I'm now going back through the car and leaning towards a complete restoration again utilizing an LS motor this time.
Actually, I work for the railroad. LOL. But I did used to work at a Corvette restoration shop for a while and had my own body shop many years ago. But thank you for the compliment.
I’ve had this car for 30 years and have well over 180k invested since I bought it. This last restomod project cost me about 50k and took me 16 years. I did all the labor except seat upholstery and rear diff rebuild. But family came first and my two sons cars came before mine.
John, you did an excellent job on both car and videos. Your series of posts may well be the most educational I've ever seen. I'm nearing the end (finally!) of my 1981 C3 restomod with LS3/T-56. One question: My Vintage Air Front Runner came with an angled thermostat housing that swivels. Maybe I missed it, but did you use the angled/swivel housing? To me it looks like a straight housing would be better, but I'm wondering if the lower radiator hose from BRP Hotrods fits the straight housing or the angled/swivel housing? Again, super job! Would be interesting to trade notes on our builds. Thanks!
I did use the swivel housing. The lower radiator from BRP works well with it. It is tight and it rests on the frame cross member, but BRP supplies it with a plastic protective cover. I haven’t had any problems with it. I will say thought that my engine does not flex with the poly mounts I used, so the lower hose has no movement. Hope that helps.
Do you run cylinder head temperature? ( Usually a ring type sensor which attaches under the spark plugs) How about exhaust gas temperatures also. I expect the ECU monitors both. Also I have heard of special coolant used that will not flash steam at air pockets voids. Don't giggle but the super charged and turbocharged Miata have an issue with air bubbles collecting at the top of the cylinder water jacket and flash steaming they say is something they guard against. Would not want to break your rubber band.. ok giggle.
All the gauges are stock and the temps are from the ECU. I understand all about air pockets. They can destroy an engine. When GM designed the LS engine they really improved the cooling over the older generation. We just stay on top of regular maintenance and do what we can to keep temps down.
The first thing you need to do is check that the main components of your system are working. Start with the thermostat, you can replace it or boil it in water to make sure it is functioning properly, opening and closing. Check that the water pump spins freely and it’s no weeping out the hole in the bottom of the shaft. I always upgrade to a high flow aluminum water pump. Check that your coolant is good. Just because it is green (or what ever color) doesn’t mean it’s still good. Begin with a cold engine. Remove the radiator cap and start the engine. Set your digital multimeter to DC volts at 20 volts or less. When the engine reaches operating temperature, insert the positive probe directly into the coolant. Rev the engine to 2,000 rpm and place the negative probe on the negative battery terminal. If the digital meter reads .4 volts or less, your coolant is in good condition. If it’s greater than .4 volts, the electrolysis additives are exhausted, and you may be in the market for a new radiator, a water pump or a heater core in the future. All of those are far more expensive than a simple coolant change. Next, if you have a mechanical fan, make sure the clutch is good. It should spin freely when cold and tighten up when hot. Clutches are replaceable and you can keep your blades. If you have a mechanical fan, you should also have a shroud. These are critical to cooling and should be intact. The biggest culprit is the radiator. Don’t be afraid to change it, or have it boiled out. If it’s original or really old, now would be a good time to upgrade to bigger AND aluminum! Now if all of that is fine check to see if the foam seals around ALL 4 sides of your radiator are intact! Including the one on top of the core support to the hood! That on is VERY important! If it’s missing, the air will run right over the top of the road and into the engine compartment. Another thing to consider is that your gauge is inaccurate. Very common. I used to have a water filled temp gauge literally screwed into the side of the head or top of the intake to verify water temp. That’s why I use Dakota digital gauges. But if yours is physically overheating, after all of this, you may want to consider a larger aluminum radiator with dual fans. I ALWAYS ran big block aluminum rads with small blocks C3 just because of the overheating issues. Fiberglass does not exchange heat like steel does and will keep under hood temps high. If you end up swapping rads, buy a new seal kit and install it. As a tip, buy an oil cooler that sandwiches between your block and filter that has a 180 degree valve that opens and closes as the oil temp changes. By keeping the oil cool, the coolant system doesn’t work as hard and cooler oil means longer engine life!!! Check out Improved Racing products for an oil cooler. Hope all this helps!!
@@C3Mods thanks so much!!! Where can I buy the Aluminum radiator with the dual fans for this vehicle? Is there a specific model you recommend, if so can you share the link
@@SamQuintani Well, I’m using a radiator specifically for an LS swap, so mine wouldn’t do you any good. These things aren’t cheap, so don’t be shocked by the prices! Check out DeWitts, I believe they are set the benchmark. Griffin is also very good, but really cater to race cars!! BE Cool is another good one and I believe they manufacture their own product. Any vendor such as MidAmerica Motorworks, Eckler’s, Zip, etc also offer swap kits but check the manufacturer and prices. If they source through DeWitt, for example, it may be cheaper to just go through them. Before you do anything Google aluminum radiator for C3 Corvette, and do your research. Again, not cheap, but better than not driving it. I smoked one of my first engines from overheating and every cylinder was oval! Turned that engine into a boat anchor. If you replace the rad, please think about replacing the water pump while everything is apart. Water pump technology has come a long way in terms of flow. The impellers are conical and vaned instead of a stamped steel prop to flow coolant. I’m NOT and ‘originality’ guy so that stuff doesn’t bother me. Just saying.
Also, purchase a rad/fan combo that has the fans in their own shroud and attached to the radiator with brackets at the top and bottom. Don’t attach fans to the rad using plastic straps that go through the cooling fins. All this does is put stress on the coolant tubes and eventually with crack them and then everything you did will be pointless.
Well built.
Thank you
great job John. Your video's are very informative and helpful. Your attention to detail is wonderful. I'm guessing your day job is in engineering. I have a 1969 roadster that I did a body off on 26 years ago and I wish I had UA-cam back then. I'm now going back through the car and leaning towards a complete restoration again utilizing an LS motor this time.
Actually, I work for the railroad. LOL. But I did used to work at a Corvette restoration shop for a while and had my own body shop many years ago. But thank you for the compliment.
very intricate work . How long did this project take from your time and at what cost if you may.
I’ve had this car for 30 years and have well over 180k invested since I bought it. This last restomod project cost me about 50k and took me 16 years. I did all the labor except seat upholstery and rear diff rebuild. But family came first and my two sons cars came before mine.
1,000,000 % humidity may be an understatement.
True, I was trying to understate it! LOL
John, you did an excellent job on both car and videos. Your series of posts may well be the most educational I've ever seen. I'm nearing the end (finally!) of my 1981 C3 restomod with LS3/T-56. One question: My Vintage Air Front Runner came with an angled thermostat housing that swivels. Maybe I missed it, but did you use the angled/swivel housing? To me it looks like a straight housing would be better, but I'm wondering if the lower radiator hose from BRP Hotrods fits the straight housing or the angled/swivel housing? Again, super job! Would be interesting to trade notes on our builds. Thanks!
I did use the swivel housing. The lower radiator from BRP works well with it. It is tight and it rests on the frame cross member, but BRP supplies it with a plastic protective cover. I haven’t had any problems with it. I will say thought that my engine does not flex with the poly mounts I used, so the lower hose has no movement. Hope that helps.
Do you run cylinder head temperature? ( Usually a ring type sensor which attaches under the spark plugs) How about exhaust gas temperatures also. I expect the ECU monitors both. Also I have heard of special coolant used that will not flash steam at air pockets voids. Don't giggle but the super charged and turbocharged Miata have an issue with air bubbles collecting at the top of the cylinder water jacket and flash steaming they say is something they guard against. Would not want to break your rubber band.. ok giggle.
All the gauges are stock and the temps are from the ECU. I understand all about air pockets. They can destroy an engine. When GM designed the LS engine they really improved the cooling over the older generation. We just stay on top of regular maintenance and do what we can to keep temps down.
My engine is overheating, what should I do? It’s a 1974 corvette small block 350
The first thing you need to do is check that the main components of your system are working. Start with the thermostat, you can replace it or boil it in water to make sure it is functioning properly, opening and closing. Check that the water pump spins freely and it’s no weeping out the hole in the bottom of the shaft. I always upgrade to a high flow aluminum water pump. Check that your coolant is good. Just because it is green (or what ever color) doesn’t mean it’s still good. Begin with a cold engine. Remove the radiator cap and start the engine. Set your digital multimeter to DC volts at 20 volts or less. When the engine reaches operating temperature, insert the positive probe directly into the coolant. Rev the engine to 2,000 rpm and place the negative probe on the negative battery terminal. If the digital meter reads .4 volts or less, your coolant is in good condition. If it’s greater than .4 volts, the electrolysis additives are exhausted, and you may be in the market for a new radiator, a water pump or a heater core in the future. All of those are far more expensive than a simple coolant change. Next, if you have a mechanical fan, make sure the clutch is good. It should spin freely when cold and tighten up when hot. Clutches are replaceable and you can keep your blades. If you have a mechanical fan, you should also have a shroud. These are critical to cooling and should be intact. The biggest culprit is the radiator. Don’t be afraid to change it, or have it boiled out. If it’s original or really old, now would be a good time to upgrade to bigger AND aluminum! Now if all of that is fine check to see if the foam seals around ALL 4 sides of your radiator are intact! Including the one on top of the core support to the hood! That on is VERY important! If it’s missing, the air will run right over the top of the road and into the engine compartment. Another thing to consider is that your gauge is inaccurate. Very common. I used to have a water filled temp gauge literally screwed into the side of the head or top of the intake to verify water temp. That’s why I use Dakota digital gauges. But if yours is physically overheating, after all of this, you may want to consider a larger aluminum radiator with dual fans. I ALWAYS ran big block aluminum rads with small blocks C3 just because of the overheating issues. Fiberglass does not exchange heat like steel does and will keep under hood temps high. If you end up swapping rads, buy a new seal kit and install it. As a tip, buy an oil cooler that sandwiches between your block and filter that has a 180 degree valve that opens and closes as the oil temp changes. By keeping the oil cool, the coolant system doesn’t work as hard and cooler oil means longer engine life!!! Check out Improved Racing products for an oil cooler. Hope all this helps!!
@@C3Mods thanks so much!!! Where can I buy the Aluminum radiator with the dual fans for this vehicle? Is there a specific model you recommend, if so can you share the link
@@SamQuintani Well, I’m using a radiator specifically for an LS swap, so mine wouldn’t do you any good. These things aren’t cheap, so don’t be shocked by the prices! Check out DeWitts, I believe they are set the benchmark. Griffin is also very good, but really cater to race cars!! BE Cool is another good one and I believe they manufacture their own product. Any vendor such as MidAmerica Motorworks, Eckler’s, Zip, etc also offer swap kits but check the manufacturer and prices. If they source through DeWitt, for example, it may be cheaper to just go through them. Before you do anything Google aluminum radiator for C3 Corvette, and do your research. Again, not cheap, but better than not driving it. I smoked one of my first engines from overheating and every cylinder was oval! Turned that engine into a boat anchor. If you replace the rad, please think about replacing the water pump while everything is apart. Water pump technology has come a long way in terms of flow. The impellers are conical and vaned instead of a stamped steel prop to flow coolant. I’m NOT and ‘originality’ guy so that stuff doesn’t bother me. Just saying.
Also, purchase a rad/fan combo that has the fans in their own shroud and attached to the radiator with brackets at the top and bottom. Don’t attach fans to the rad using plastic straps that go through the cooling fins. All this does is put stress on the coolant tubes and eventually with crack them and then everything you did will be pointless.
DeWitts.com