Author Topic: I could use some help with an engine decode.  (Read 2092 times)

Offline DanMcG

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I could use some help with an engine decode.
« on: March 12, 2020, 11:47:13 AM »
I just picked up a 400 ci 3951509 basket case and I'm have a problem decoding the numbers on the right front of the block.

The numbers are F0317T space S
and T77518541  Is the T77 for truck and the rest the vin number?

Can anyone help me out here? Thanks

« Last Edit: March 12, 2020, 11:50:44 AM by DanMcG »

Offline zieg85

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Re: I could use some help with an engine decode.
« Reply #1 on: March 12, 2020, 12:31:51 PM »
Here is 2 possibilities...TLS   1977   400   conv.cab                   R LF4   175   4   K-10 to 2500
                                 TLS   1979   400   con. cab, a/t, Cal   R LF4   170   4   K-10 to 2500
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline zieg85

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Re: I could use some help with an engine decode.
« Reply #2 on: March 12, 2020, 12:33:45 PM »
Those are the only 2 I could find looking for engine code T_S and 400 CID
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/

Offline DanMcG

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Re: I could use some help with an engine decode.
« Reply #3 on: March 12, 2020, 12:56:48 PM »
Thanks zieg85 , but it's a 2 bolt main. 
Edit: or does the"4" you listed stand for four barrel?


« Last Edit: March 12, 2020, 01:09:34 PM by DanMcG »

Offline zieg85

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Re: I could use some help with an engine decode.
« Reply #4 on: March 12, 2020, 02:45:03 PM »
Thanks zieg85 , but it's a 2 bolt main. 
Edit: or does the"4" you listed stand for four barrel?

4bbl carbination
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/

Offline DanMcG

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Re: I could use some help with an engine decode.
« Reply #5 on: March 13, 2020, 05:15:39 AM »
Can anyone explain the T77.... number? I'm been searching the net and it doesn't make sense to me. It has 9 digits and everything I read about has 8.

Offline Poppy 87

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Re: I could use some help with an engine decode.
« Reply #6 on: March 14, 2020, 07:07:59 PM »
Could one of those character be a "Z" instead of a 7?

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Offline MIKE S

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Re: I could use some help with an engine decode.
« Reply #7 on: March 14, 2020, 07:53:28 PM »
I think T is for Tonawanda engine plant

Offline DanMcG

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Re: I could use some help with an engine decode.
« Reply #8 on: March 15, 2020, 11:02:41 AM »
So what I have been told is that if the second 7 is a Z then it would be K= GMC, 7=1977 and Z =Fremont Ca plant.
And as far as it being a 77 or 79, the casting date is October 18, 76 so 77 would have to be the build date.

Thanks for the input everyone!
« Last Edit: March 15, 2020, 11:05:44 AM by DanMcG »

Offline Poppy 87

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Re: I could use some help with an engine decode.
« Reply #9 on: March 15, 2020, 12:39:40 PM »
So what I have been told is that if the second 7 is a Z then it would be K= GMC, 7=1977 and Z =Fremont Ca plant.
And as far as it being a 77 or 79, the casting date is October 18, 76 so 77 would have to be the build date.

Thanks for the input everyone!
Glad to see that you found it!

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Offline JohnnyPopper

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Re: I could use some help with an engine decode.
« Reply #10 on: March 15, 2020, 03:11:13 PM »
Just a question: why is the ancestry of motor parts important?

I mean, is there a quest to make a project 'correct'?

My question is not to knock anyone who might be a purist, I just haven't noticed this as a trend.

Now if you're talking VW, those purists are in a rare stratus, just ask them! 
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction