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Discussion Starter #1
ok so my car is a late march 67 with a c code 289. did the 67 c codes come with flat top pistons or dished pistons. my car has flat tops with valve clearance indents and they are just below the top of the hole on tdc. is this normal or was it some kind of special order option. it was rebuilt but it was rebuilt with identical parts to what came out. it is exactly as it left the factory engine wise. i have noticed that the engine seems to have fairly high compression to the point that if you push start it it just locks the tires before it spins the engine. i dont know if thats normal or not. anyway i was just wondering if you guys knew what pistons they used in the c codes
 

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All C codes had dish tops with valve relief. What you describe could also be a weak battery or starter, or initial timing is advanced too much.
 

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Discussion Starter #3 (Edited)
i said it has flat tops not dished pistons. i had it apart and i saw them and my dad verified that it came from the factory with them. it is a factory c code engine. the timing is set at 10 degrees before tdc. the battery is fine. so this is a weird engine that it came with flat tops but was a c code. i wonder if since it was a model year end car they just cobbled together whatever they had laying around
 

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He said it has flat top pistons with valve relief. bbp I was repeating what you said.
 

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Discussion Starter #5
so can any one tell me anything else about this could it have been a factory mistake or special ordered with the flat top pistons
 

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Very unlikely to be special ordered with flattop pistons. No one at the dealership at new car delivery time frame would tear down an existing engine, nor build a special engine just for the insertion of factory flattops. The only way THAT could be done was to specify an A code 225 hp engine in 1967, just a few dollars more on the order form than the dished piston C code.
The OP's engine must have been rebuilt with the flattops, or the original C code replaced under warranty with a flat top A code engine, and then had that engine subsequently rebuilt down the road, earlier in its life.
 

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A lot can happen in 44 years.
 

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Discussion Starter #8
what i am wondering is if they ran out of c code pistons and just stuck a code ones in it or if they screwed up and put a C code intake on an A code engine. that car is completely stock and nothing has been changed in at least 38 years. when it was rebuilt what came out got identical replacements. it stayed exactly as it was.
 

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Answer: NO.
Something else occurred. No 2V's came with flat tops from the factory. Very easy for someone to swap pistons at rebuild because face it, who would know? Besides, it was a popular mod at rebuild in anticipation of adding other goodies. It did give the engine a bit more spunk. It's a nice dream, but alas, that is all it is. Sorry my friend.
 

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Discussion Starter #10
it wasnt rebuilt though it had never been touched before it was opened. it doesnt have any other goodies its otherwise stock. when it was rebuilt it had the original bore
 

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That's nice. But you are predicating your argument on the honesty of someone you do not know. Picture this: rebuilder orders the wrong thing (say it isn't so!). Hmmm. Does he send it back, lengthen the time line and PO the customer, or just rock on with what is available? A lot can happen in 44 years. I can come up with more 'why it's not right' than why it might be. Run out of 2V piston's? The most ordered 289? Really man? I seriously think this would have been heard of - in the last 44 years. Just sayin'. Again, I'm sorry this does not fit your view. The truth often sucks, and does not care one bit about it.
 

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it wasnt rebuilt though it had never been touched before it was opened. it doesnt have any other goodies its otherwise stock. when it was rebuilt it had the original bore

Has this car been in your family it's entire life? Were you there during the rebuild? How could you possibly know if the EXACT same parts were used? If you want check the head casting numbers. That will tell you if it's maybe an a code engine or if it's just a c code with flattops.

People already gave you the correct answer and you still wanna argue with them. Besides, is this going to be a concourse restore? If not then why does it matter? Sorry if my post came off harsh. But seems like your fishing for someone to agree with you.
 

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Heads are no different between A and C 289's until 68 when there were no
A 289's. The only difference in the 68 289 head was a larger combustion chamber.
 

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" my car has flat tops with valve clearance indents and they are just below the top of the hole on tdc. is this normal or was it some kind of special order option."


Quote


Based on your description,it sounds like your motor has stock C code pistons. If you could take a picture of the pitons and post it we can I.D. Them for you no problem.
 

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Terminology

All C codes had dish tops with valve relief. What you describe could also be a weak battery or starter, or initial timing is advanced too much.
I'm betting he has STOCK C-Code pistons. He may be getting "dished" confused with "domed." My 66 engine had the factory (and stock P/N) pistons in it when I rebuilt it a few weeks ago. Now I realize these pistons are of the "dished" variety.

I didn't even realize they were dished because I never really looked into the different categories of pistons. I did notice quickly that they had the valve reliefs.

Here's what they looked like.


Some 289's had these below, but I don't have my Mannel book at work and I don't remember which ones.
 

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I'm betting he has STOCK C-Code pistons. He may be getting "dished" confused with "domed." My 66 engine had the factory (and stock P/N) pistons in it when I rebuilt it a few weeks ago. Now I realize these pistons are of the "dished" variety.

I didn't even realize they were dished because I never really looked into the different categories of pistons. I did notice quickly that they had the valve reliefs.

Here's what they looked like.


Some 289's had these below, but I don't have my Mannel book at work and I don't remember which ones.

Yup,
The upper photo is a stock C code variety whereas the lower piston is an A code piston.Which looking at the two would explain the compression difference between A and C code engines.
 
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