1969 Authenticity
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Instructor
Joined: Jan 2006
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From: Okanagan BC
1969 Authenticity
Hello all....I've recently purchased a 1969 4-speed roadster with a 427/390, and I was wondering how I can tell the car was truly a 427/390 car from the factory, other than numbers. I want to learn more about my car. What should I look for? Can anyone help? I'm also curious of the differences between the 390 and 400 horse 427 cars, other than the tri-carb setup. Any help is greatly appreciated.
Former Vendor
Joined: Oct 2007
Posts: 2,092
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From: walpole ma
the yellow line on your tach will start at 5400 and the redline will start at 5600.that is for 390 and 400 hp cars. the 435 cars have a redline close to 6500.Your rear end has different end caps than the small block cars.Your car should have a rear sway bar as well.
Thread Starter
Instructor
Joined: Jan 2006
Posts: 116
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From: Okanagan BC
the yellow line on your tach will start at 5400 and the redline will start at 5600.that is for 390 and 400 hp cars. the 435 cars have a redline close to 6500.Your rear end has different end caps than the small block cars.Your car should have a rear sway bar as well.
Pro
Joined: Sep 2007
Posts: 735
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From: Harleysville PA
the yellow line on your tach will start at 5400 and the redline will start at 5600.that is for 390 and 400 hp cars. the 435 cars have a redline close to 6500.Your rear end has different end caps than the small block cars.Your car should have a rear sway bar as well.
....and you should check the radiator and shroud - these are specific to BB cars. The front coil springs are also different on BB cars. On the engine, one difference is that the 400 and 435 hp engines have 4 bolt mains - the 390 hp engine has a 2 bolt main even though the block is otherwise the same. The 390 has the same heads as the 400 hp engine.I just purchased a 427/400 roadster with a/c and just started to put it back together. I have been asking the same questions and doing research and it is really not possible to definitively tell if the car came from the factory with a BB engine (except the matching VIN on the engine pad) unless you have authentic paperwork. You should also check every piece of the drivetrain to verify that it was cast and/or assembled before the build date of the car.
I am planning to get an NCRS judge out to look at my car before i assemble it to check everything over and give me an expert opinion - this is the best that you can get without documentation (so they tell me). Let me know if you need anymore help. Dan
Thread Starter
Instructor
Joined: Jan 2006
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From: Okanagan BC
Pro
Joined: Sep 2007
Posts: 735
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From: Harleysville PA
my car came from Tennessee 3 weeks ago and i've just finished POR-15ing the frame and am ready to bolt the rear crossmember and differential on this week (the frame was already sandblasted
). just placed a $3K order with corvette central last night and i told my wife that this will last me for a year
you can take advantage of the great exchange rate and get some good deals
lets stay in touch.
). just placed a $3K order with corvette central last night and i told my wife that this will last me for a year you can take advantage of the great exchange rate and get some good deals lets stay in touch.
Thread Starter
Instructor
Joined: Jan 2006
Posts: 116
Likes: 0
From: Okanagan BC
my car came from Tennessee 3 weeks ago and i've just finished POR-15ing the frame and am ready to bolt the rear crossmember and differential on this week (the frame was already sandblasted ). just placed a $3K order with corvette central last night and i told my wife that this will last me for a year you can take advantage of the great exchange rate and get some good deals lets stay in touch.
). just placed a $3K order with corvette central last night and i told my wife that this will last me for a year you can take advantage of the great exchange rate and get some good deals lets stay in touch.
Instructor
Joined: Dec 2004
Posts: 236
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From: Clearwater Florida
Go the NCRS web site and then to their book store or library. Buy the Technical Infomation Manual for your year car. It will have the definitive answer on how BB cars differed from SB cars.
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Instructor
Joined: Sep 2007
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From: Memphis TN
BB cars have a 27 inch radiator. The passenger side upper bracket is offset one inch to the right from a 26 inch radiator. Measure the core between the tanks. If it has A/C, it will use a special smaller brass overflow tank and have a bag for the washer fluid instead of a washer fluid jar.
The only difference on a C3 that I am aware of with the fuel line is that Holley equipped cars did not have a vapor return line next to the fuel supply line on the passenger side. A 390 would have 2 lines, but others would have 1.
The only difference on a C3 that I am aware of with the fuel line is that Holley equipped cars did not have a vapor return line next to the fuel supply line on the passenger side. A 390 would have 2 lines, but others would have 1.