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Discussion Starter #1
Thought someone hear would know info or where to look.
Friend's uncle has one for sale. Going off what friend has told me. It.s a convertable with the 421 tri power engine. Not sure right now about type of trans. He said it had a shifter in floor. Underneath and frame and floors are done. Has all the pieces to complete. Engine has been checked or rebuilt? New top. Friend told me what it needs is bottom of rear quarters and both doors. Is there any place i should look for rust or bad spots for these cars?
Value?
 

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Pics please.

Hard to say what it's worth... if it's numbers matching, and all OE motor/drivetrain, then it's probably worth something. But if it's cobbled together, it's probably worth $3000-4000 at best in the condition you're describing. Ask me how I know...
 

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Discussion Starter #7 (Edited)
1965 engine usage 389 ci

Can a 1965 389 be used in any pontiac car. I am not sure how coding works. Is it specific to the car it came out of, date coding also? YG code
 

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Discussion Starter #8
Just found this thread back. Talked to guy last night and he gave me the codes off engine. YG and then a string of numbers. I don't no what the numbers mean but i looked up the YG and comes back as 389 tri with auto trans. He said there were numbers on the timing chain cover. My friend said that he was not clear on 389/421 size. He had not talked to his uncle for about a year and thats why i told him to go back and look at car in shop. He said it had a auto trans with a gauge next to shifter. Black interior and said it appeared to be blue at one time. He told his uncle that him and i would stop out some time and look.
 

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If it's a '65 YG, the engine is a 389 tri with a 4 speed. All YG's had 4 speeds except for '71. They didn't make any YG 421's. You can check the date code by the distributor to verify the year.... Ex. D225.
 

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Discussion Starter #11 (Edited)
I looked in my Hollinder book and it showed code only for 1965 and for auto trans. There were 2 engine desinations for the 338 HP. 1 for manual and 1 for auto. The 1 for the auto was the correct one and did not continue into 1966. Numbers are written on paper at home . Will have friend look at date code when he gets a chance for block. Noticed link from other member and looks like there is a misprint and my memory was right. YG should be Auto trans
 

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Discussion Starter #12
I believe there is a misprint. The link says the Y code is for auto. But when you look up my code it shows a 4 speed. The car it is currently in is a 65 389 auto with tri power intake. and looks all stock. My hollinder at home shows it to be a 338 HP engine with tripower and auto trans. Also this code was not used until later years, just like my hollinder shows.
 

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Here's a summary of all the YG codes:

YG A-body 73 400 230 4-speed L-78 T 1x4 481988 2
YG B-body 71 455 280 Turbo 400 L-75 1x4 485428 2
YG B-body 65 389 338 4-speed 3x2 9778789 4
YG F-body 73 400 230 4-speed L-78 T 1x4 481988 2
 

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Do you know the block cast code? Should be above or under the engine code YG.
Actually, the number above the engine code would be the unit number. The block casting code would be located on the distributor pad ('64 - '66). In '67 - on, it was located behind the #8 cylinder. If it's a '65 389, the block casting code should be 9778789.:)
 

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Discussion Starter #16
Will call guy to get that and will post. My buddy's uncle has had car for long time and told him last night that it has all the original drive train. I think there is even a vacumme guage by shifter. Buddy told me that the engine is all there but the carbs are removed and holes are covered over. Said there is shelves and tubs of parts lineing garage. He did tell my buddy that everthing is there a couple of times thought. Sounds like his uncle idemized things. He hasn't really asked alot of questions about car till i get with him to look at and have more knowledge of what we are looking at before we think of price.
Trying to get info about things before we go. I want to find out about the trans and rearend ratio.
 

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Discussion Starter #19 (Edited)
I am in southern ohio. So is my hollinder book wrong about the auto. Did they make any 338 HP with auto trans? i just noticed it should be a 4 bolt if 1965?
 

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I merged your threads since you're talking about the same motor in both places.

Here's all the '65 auto 389's. None had 338hp. A YH 421 auto had 338hp. The only tri-power with an auto was a YR 360hp and it came on a GTO. This is according to the documentation I have........... 4 bolt mains were used in a 421..

XC B-body 65 389 325 Turbo 400 1x4 9778789 2 low comp
YA B-body 65 389 256 Turbo 400 1x2 9778789 2 AC
YB B-body 65 389 256 Turbo 400 1x2 9778789 2 AC
YC B-body 65 389 290 Turbo 400 1x2 9778789 2 AC
YD B-body 65 389 290 Turbo 400 1x2 9778789 2 AC
YE B-body 65 389 325 Turbo 400 1x4 9778789 2
YF B-body 65 389 325 Turbo 400 1x4 9778789 2
YH B-body 65 421 338 Turbo 400 1x4 9778791 4
YR A-body 65 389 360 Powerglide 3x2 9778789 2 GTO
YS A-body 65 389 335 Powerglide 1x4 9778789 2 GTO
 
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