Was a 3965577 intake manifold on any late 69's?

[Guest]

My wife's 69, with a build date of 12/15/1969, was judged in Houston today. The judge took major deduction points because it has a 3965577 intake manifold, and the judging manual says it should be a 3927184. The previous owner had the car judged in Waco, Texas in November, 2002, and a very well known and respected judge took off only two points for an incorrect gasket.

I believe both the judge today and the previous judge to be two of the best, and I am just trying to find out what is correct. If it is incorrect I will change it, but if late 69's had the 3965577, I don't want to change it.

Thanks,
Allen and Lou Ann

[Guest]

Re: Was a 3965577 intake manifold on any late 69's

I forgot to mention that it is an L46 and the 3965577 is correct for a 1970 350 engine.

[Joe L.]

Re: Was a 3965577 intake manifold on any late 69's

Allen and Lou Ann-----

Although the GM casting #3965577 is not regarded or recognized as having been used for 1969 Corvettes, considering the build date of the car, I think that it's very possible that it's original to the car. The thing that would help verify this is the casting date found on the manifold. If the casting date is consistent with the engine's build date and precedes the car's build date, then I'd say it's a virtual certainty that the manifold is original to the car.

The GM #3965577 manifold casting was being used well prior to the end of 1969 on 1970 models for other Chevrolet models besides Corvette and Camaro (since the 1970 models for those were not released until after 1/1/70). So, it's a certainty that there would have been manifolds produced with a casting date correct for your car, but originally installed on another Chevrolet. However, the chance that such a "correctly dated" but "incorrect casting number" manifold could have been later installed on your car is extremely remote, at best. So, if the casting date is right for the car, I'd say that the manifold is, without a doubt, original to the car. If the casting date is later than the engine build date, then it's very likely that the manifold is NOT original to the car. I would think that the judges would have used the casting date as a "clue" to the originality of the manifold considering the build date of the car.

The primary difference bewteen the 3927184 manifold and the 3665577 is the carburetor heat groove. The former manifold has one and the later manifold does not. However, I think that it's very possible that this later manifold could have been used with a 1969 carburetor. It should have required engineering approval, but I would think that such approval could have been obtained.

Out of curiousity, what is the assembly date of the engine, the casting date of the block and the casting date of the manifold?

[Guest]

Re: Was a 3965577 intake manifold on any late 69's

Joe,

Thanks for your response. I am at home, but the car is still at the show until Sunday evening. I will get the assembly date of the engine, the casting date of the block and the casting date of the maniflod, and post them Sunday night or Monday morning.

Thanks again,
Allen and Lou Ann

[Tom S.]

Re: Was a 3965577 intake manifold on any late 69's

Alan
I have a 69 l-46 also. I don't find any numbers on mine except the firing order cast #s and abig W with a decoration around it. C an I safely assume that this is not he correct intake?Where exactly are the numbers? If mine is in fact not correct I do want to bet the correct one. But after your dilema I will wait to hear more on this.

Thanks Tom

[Guest]

Re: Was a 3965577 intake manifold on any late 69's

Tom,

The standard intake manifold for a 69 L46 is a 3927184. You should find the number behind the carburetor. My car is a very late 69 and has a 3965577 on it. I cannot verify that this is the original intake manifold.

I would be interested to know your engine assembly date, intake manifold number and intake manifold date.

Thanks,
Allen

[Tom S.]

Re: Was a 3965577 intake manifold on any late 69's

Alan
The build date for my car was feb I think 11th. But when I get a chance I will look further for the # AND THE DATE AND WILL LET YOU KNOW. Is the date stamped near the part # or is it cast. Stamped I would imagine.

Tom

[Guest]

Re: Was a 3965577 intake manifold on any late 69's

Tom,

The date code is cast close to the part number code. It will be a letter followed by 2 or 3 numbers. Such as A129 which would be January 12, 1969.

Allen

[Tom S.]

Re: Was a 3965577 intake manifold on any late 69's

Alan
I found the part # 3890490 on my intake. There is a flat spot below it where I assume the date code should be, but I can't read it. The previous owner put a bi holley on it and it is right over that spot. I know I need to change out the carb, and possibly the intake.

Tom