I have what I believe to be a '68 Z28 long block. Pad #'s were decked off.

Block casting # 3914678
Block date I 23 7
Head casting 3917291
Head dates O 20 7, O 22 7
Crank (forged) stamped 3279
Piston id # 3927176
Balancer stamped 7173

Any opinions on what the motor is worth?

Since the numbers are decked off, the motor is worth the sum of it's parts. Block will not be worth anymore than a 350 block.

Thanks for the opinion.

Just to clarify, any / all motors (no matter how rare or valuable) that have been decked and the #s are gone is worth the parts?

Yes. Aside from the actual condition of the blcok (bore, cracks, etc.) it's the numbers which have been stamped on them which really make them valuable.

The sum of the parts = a 302 therefore it is worth more than a 350 but not as much as it would be if it had a MO stamp on it.The only part you have that isnt easy to find is the crank.JMO

A 68 with a DZ stamp is worth the same as a decked block. (actually might be worth less)

be nice guys.....

a 1968 302 should not have a "DZ" stamp at all...

it shall be "MO"

The problem, Brian, is that there is no definitive ID to say what it is or was. Someone would have to take your word it is an original 1968 302 engine.

I thought a 3914678 was a '68 only block for everything including 302. 327, and the 350....and what made the motors different were the guts.

This motor (which has been crated and stored the past 20+ years) has a 3279 stamped crank (MO 302) with 11:1 (68 Z28) piston, date correct / casting correct 3917291 heads. This motor by definition is a '68 302.....all the correct GM parts...the only thing missing is the pad stamp.

My bad MO it is.I will go back and correct myself.

I thought a 3914678 was a '68 only block for everything including 302. 327, and the 350....and what made the motors different were the guts.

This motor (which has been crated and stored the past 20+ years) has a 3279 stamped crank (MO 302) with 11:1 (68 Z28) piston, date correct / casting correct 3917291 heads. This motor by definition is a '68 302.....all the correct GM parts...the only thing missing is the pad stamp.

You are correct and it is more valuable than a 327 or 350 but not as much as if it had the MO stamp.Everything you have could be found seperately and put together to make a 302.Not saying it was but it could be done.Not having the stamp decreases the value.

I guess I need to qualify my question........let me restate it. For anyone with a documented '68 Z28 with the wrong motor.................

I have what I believe to be a '68 Z28 long block. Pad #'s were decked off.

Block casting # 3914678
Block date I 23 7
Head casting 3917291
Head dates O 20 7, O 22 7
Crank (forged) stamped 3279
Piston id # 3927176
Balancer stamped 7173

Any opinions on what the motor is worth?

I will bite. If I was putting together a NOM Z/28 I guess it might be worth $1000. If I was unscrupulous and a scumbag wanting to re stamp it to make a clone to sell maybe $2000. A '68 Z/28 w/o the original motor is a hard sell as a real Z/28. If I had one that needed an MO motor I would be happy to get it and be truthful about it.

I will bite. If I was putting together a NOM Z/28 I guess it might be worth $1000. If I was unscrupulous and a scumbag wanting to re stamp it to make a clone to sell maybe $2000. A '68 Z/28 w/o the original motor is a hard sell as a real Z/28. If I had one that needed an MO motor I would be happy to get it and be truthful about it.

Wow! Unscrupulous, scumbag.......for a re stamp?? Even the NCRS guys allow for a re stamp if the casting numbers, dates, and componets are "ALL" correct. I wasn't there when this motor came off the assembly line and I can't say for sure it was born a MO 302 without the stamp but I was told it came out of a Z and all the numbers, age, over all condition look to support the story.

Naturally if everything checks out 95% you would be ok to prove a z but without the stamping to many people throw up the red flag which is a shame in a way but there are so many scammers anymore i dont blame them. Its crazy how much the value goes down which sort of makes sence but doesnt. However, i feel an honest persons word should be enough to still give a hell of a value on a z-28 for which else the car does have the rest of the goodies. Its like this one guy who i know said " A z can be just another camaro without all the stuff but a proven z can fill my beer fridge for life"... .. i had to add that quote there haha

any other possible stamp location on this block...besides the pad?

top of this block...flat deck, at the rear of the block there is what appears to be a tiny "z" stamp.....mean anything to anyone?

I'll try to post a pic tomorrow.

I guess I need to qualify my question........let me restate it. For anyone with a documented '68 Z28 with the wrong motor.................

I have what I believe to be a '68 Z28 long block. Pad #'s were decked off.

Block casting # 3914678
Block date I 23 7
Head casting 3917291
Head dates O 20 7, O 22 7
Crank (forged) stamped 3279
Piston id # 3927176
Balancer stamped 7173

Any opinions on what the motor is worth?

it's still the "wrong motor". you're answer will be the same. ultimately, it's worth what someone is willing to pay. to ask the question again makes it sound like you're fishing for something. you asked for answers, and we, collectively, are trying to give you one in good faith. i would love to tell you it's worth a million, but i wouldn't buy it if i had a million to spare. anyone else?

Assuming it is a real Z motor, it is worth "the moon" to the original car it came with. Since the pad numbers have been decked off, it obviously can never be reunited with its original car. Therefore, it can only ever be a motor "built to 302 specs" and is worth only the price of building one from scratch using correct parts and a correct casting block.

Sad, but true. I'm sure no one ever gave any thought back in the day about decking off the numbers. Who would have ever thought it would be a big deal today?

Assuming it is a real Z motor, it is worth "the moon" to the original car it came with. Since the pad numbers have been decked off, it obviously can never be reunited with its original car. Therefore, it can only ever be a motor "built to 302 specs" and is worth only the price of building one from scratch using correct parts and a correct casting block.

Sad, but true. I'm sure no one ever gave any thought back in the day about decking off the numbers. Who would have ever thought it would be a big deal today?


Andy is correct - it's like finding a perfect 1969 Z/28 Camaro without a docs, Title, VIN plate, or partial body stamps. You know it is a true Z/28, but you will never be able to put it back on the road as an original Z/28.

Wow! Unscrupulous, scumbag.......for a re stamp?? Even the NCRS guys allow for a re stamp if the casting numbers, dates, and componets are "ALL" correct. I wasn't there when this motor came off the assembly line and I can't say for sure it was born a MO 302 without the stamp but I was told it came out of a Z and all the numbers, age, over all condition look to support the story.

Come on. Understand what I am saying. NCRS does not condone retamping etc. for deceit. Scumbags do it for deceit.

Wow! Unscrupulous, scumbag.......for a re stamp?? Even the NCRS guys allow for a re stamp if the casting numbers, ...

yuup, i agree, sounds about right to me ... :)

regardless if the queen allows it, it isn't right and will only be used to deceive down the road

Come on. Understand what I am saying. NCRS does not condone retamping etc. for deceit. Scumbags do it for deceit.

darn fine line there IMHO