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Old Jul 6, 2003 | 08:58 PM
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Default Engine Numbers Question

I am in the process of purchasing a 68 Big Block 1200 miles away and a question on the numbers has come up. It is a 400hp car that was built in the July / August time frame of 1968.... torwards the end of production. The gentlemen sent me the numbers that reflect 1969 casting numbers for the head and the block. He says the stamp pad appears correct and those numbers match and the engine assembly date jives with assembly date of the car. I told him where to check for the casting date for the block. My question is this, has there been cases where 1969 casting numbers have shown up in late 1968 cars? If he comes back with a June/July cast date, someone went through an awful lot of trouble to forge a 400hp car. It is a documented 3 owner survivor, and the current owner has had the car since 1991. Any facts or opinions would be greatly appreciated.
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Old Jul 6, 2003 | 09:28 PM
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Default Re: Engine Numbers Question (mac383)

I believe the only casting number for 400HP block that was used in BOTH 68 & 69 is 3935439. the correct head casting number should be 3917215 for 68 and 3931063 for 69

What numbers have you got??

Best regards,
Joe
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Old Jul 6, 2003 | 10:41 PM
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Default Re: Engine Numbers Question (jyounane)

Iam referring toa black book thats states in 1968 block casting numbers were as follows:
3916321 427ci., 390hp, 400hp, 430hp, 435hp.
3935439 427ci., 430hp, 435hp.
The heads on the car reflect 1969 casting numbers.
Where did you get the information that indicates that casting #3935439 was used for 400hp cars in 1968?
Thanks for your help. :banghead:

John
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Old Jul 6, 2003 | 10:51 PM
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Default Re: Engine Numbers Question (mac383)

I'm using the "Vette Vues Fact Book of the 1968-1972 Stingray" by M. F. Dobbins. I can fax you the pages if you like. It clearly shows 3935439 as a 68 400Hp block. What head numbers do you have?

My early 69 390 HP has one late 68 head and one 69 head, and they were definitely original.

Have fun!
Joe

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Old Jul 6, 2003 | 11:12 PM
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Default Re: Engine Numbers Question (jyounane)

you should also check out www.mortec.com and though this is not a Corvette specific site, shows that the 3935439 block was used in 68 & 69.

It also shows the 3931063 heads were used in 68. The Vette Vues book shows the 3931063 heads used on the 390HP in 68.....some could have made it onto 400HP motors ???

Joe
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Old Jul 6, 2003 | 11:14 PM
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Default Re: Engine Numbers Question (jyounane)

The car's block casting is 3935439 and the heads are both 3931063. All 1968 built July 12 1968. That would be great if you could fax it to me. The number is 734-327-6246. Thanks for the help.

:thumbs:

John
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Old Jul 6, 2003 | 11:24 PM
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Default Re: Engine Numbers Question (jyounane)

My reference shows 3935439 used only for 430hp and 435hp motors in 1968 and mentions nothing about using 3931063 ona any motor in 1968. Could I trouble you to fax the head information also?

Thanks,

John
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Old Jul 6, 2003 | 11:25 PM
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Default Re: Engine Numbers Question (mac383)

You have FAX :)
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Old Jul 6, 2003 | 11:33 PM
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Default Re: Engine Numbers Question (jyounane)

Thanks, it will be morning before I retrieve the fax, who would have thought a gent from Austraila would bailout a Detroit boy on a car question!!
Thanks again :hurray:

John
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Old Jul 6, 2003 | 11:44 PM
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Default Re: Engine Numbers Question (mac383)

John,

There is a lot of information available on this forum, and I've had a lot of help from members. Pleased I could help you on this. I'm a little surprised that more members haven't chimed in to confirm the numbers question. Perhaps they are all in July 4 mode?

I bought all the books I could in 1990 when I was living in Ca. and finally bought my 69 coupe in Texas after a lot of research. I know what you're going through. In the end I was 99% sure of the car and panicked when another buyer got interested and bought the car sight unseen. After countless $ & hours I'm still happy.

Good luck,
Joe
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