Strange numbers and codes

[Peter1962]

Hi everybody,

Since saterday I have purchase a corvette 1970.
Now people are telling me that I have a LT-1 block in it.
They don't know for sure if it's a real original LT-1 or not.
Many things are strange in this corvette. My tacho goes to 5500rpm and I have airco. Here the numbers I found:

Block number: 3970010 V0325XCD
Also on the block 3927184 conv4 F39
carb. 7029207
A/C 03210
heads 3991492
Exhaust 3846559 3989036

We put the fueltank down, but there was no sticker / form on the fueltank.
Please help.

Thanks,

Peter

 

[MR Sixpack]

Hi Peter,

try this webadress www.stingray.nu and then click on tech tips.
Good luck.
Best Corvetteregards



Svempa

 

[Tweek]

I found the "3970010" in my book for engine blocks, here is what it says...This block was a completely new design for small block engine cases. It came into production sometime in late April or May of 1969 and was used through 1975. It was produced in 2- and 4- bolt main configurations and these applications varied greatly from year to year....Your F39 I believe is a date code which would be "F" for June, "3" for the third day, and "9" for 1969. I can't find your head casting numbers in model years 1970 to 1975, maybe someone with other books can come along and find them. Carb number doesn't come up in that modle year either. Exhaust manifold # 3846559 should be the left hand side and used in 1970 and 1971 Corvettes, # 3989036 was used on the right hand side in years 71, 72, and 75, and on the left on years 74, and 75. How about your VIN # what is that?

Ron

 

[Peter1962]

Thanks, but that facts I knew.
My problem is: Is it an LT-1 or not?
And de Code XCD on the engine. Some people told me that it is the original block. In 1969 GM produced many blocks and the blocks who where not placed that year in a corvette 1969 where used in a 1970 corvette. Because it was the wrong code for a 1970, GM gave it the code XCD. Others told me that it was a replacement block, proberly the buyer had from the start problems with the original block and GM replaced it with the 1969 block.

What is the true story about XCD and do I have a real LT-1?

Peter

 

[Peter1962]

3991492....Year 70......350 ci..........LT1,Camel hump,accessory holes,64cc, straight plug

My vin is 194370S411240

I know the block, carburetor and the intake are from 1969.
The exhaust, heads and airco from 1970.

Thanks Ron and swempa for the quick reply.

Peter

 

[71LS5]

Peter, The original LT1 engines carried a code that followed the engine number and was found on the engine stamp pad. LT1s had a code of CTK, CTR or CTU. A/C was not available on original LT1s in 1970. Also, the Tach for an LT1 should have a red line of 6500(I think). I can't find anything that would have an XCD. The '69 codes use 2 letters. It could be a replacement block, Maybe someone with more knowledge than me can help.

 

[Tweek]

Peter, I know somewhere sometime I read an article in Chevy High Preformance, or maybe not even a article, but in the front of the magazine there is a section where people write in and ask questions, and I remember one about "X" code engine blocks. I've been through all my back issues and can't find it anywhere, and I might add it's really bugging me, but I would go to there web site and do a search, or even E-mail them your code and see if the can help. I will keep looking, cuz I KNOW I seen it somewhere!

Ron

 

[rainman]

I vote for no, not an LT-1.

 

[Robert N]

My tacho goes to 5500rpm and I have airco.

All 70 Lt-1s had a 6500 tach and no A/C.

Robert

 

[Peter1962]

Oke, I found out that it's not a Orginal LT1. One of the previous owner rebuild it to an LT1 and now I don't know if the seller of this Corvette has ripped me of, because he sold it as an LT1. I have paid 25500 dollar for this corvette and the handbrake wasn't working, some fiber-optics doesn't work, the windshieldcover doesn't work and I have to paint the hood again. I can't say that I was looking for a real LT1, but because I thought it was an LT1, I found it not expensive. Am I ripped off?

Peter

 

[Vettehead Mikey]

Did the seller put in writing that the car was an original LT1? If not, there's not much you can do. 25.5 would be expensive in N.Am for this car, but I have lost touch with Euro Corvette prices.