Engine code question

73GTO · 08-25-2007, 06:24 PM

Can anyone tell me if the 1973 GTO Engine code "ZC" is exclusive to only that year and model vehicle, I have found no other reference after searching for over 4 years of the "ZC" engine being installed in any other Pontiac model. If anyone thinks it is not an exclusive engine to only the 1973 Pontiac GTO please offer up the proof for investigation by myself.

Thanks ,,, Please help me solve this mystery

abright52 · 08-25-2007, 06:53 PM

Also used on V6, Manual Firebirds:

http://www.mprime.com/ProjectFirebird/FB11-specs.htm

73GTO · 08-25-2007, 07:09 PM

OK, This is a 73, 455 engine, Looking for info applying to the 455 only. i'm trying to find out if the "ZC" 455 was used in any other models. I have found no evidence that it was. Thanks

05GTO · 08-25-2007, 07:41 PM

I am not finding any info on the letter code ZC for any pontiac engine including those 455's used in 73,

73GTO · 08-25-2007, 07:50 PM

I have one. Here's some GTO info from GTO Alley
http://www.gtoalley.com/engcodens.html

Year CID Casting Number
1973 455 485428

1973 Letter Code CID HP Trans
ZC 455 250 Auto

All these number match on my engine

73GTO · 09-05-2007, 02:47 PM

What do you think?

05GTO · 09-05-2007, 05:35 PM

That is a beautiful 67 Grand Prix,

GTO JUDGE · 09-05-2007, 06:05 PM

Quote:

Originally Posted by 73GTO

What do you think?

Absolutely GORGEOUS.... Been a long time since I seen a pic of one let alone in person.

73GTO · 09-07-2007, 05:38 PM

Thanks for the compliments. There are three things I dig about this car (1) it has a complete GTO drive-train (2) The hide-away headlights which we all know was on the GTO as well (3) the tailights look like the GTO back-end. The car screams muscle just looking and listening to it.

You know, Maybe I should get a GTO - My brother-in-law will have his 69 convertable, #'s matching goat back this weekend from the paint shop, the engine was done last year. I"ll post some pics when I see it, I'm calling him now.

I still haven't found anymore information on the engine code though, Another little thing is there is no VIN# stamped by the timing cover like there should be. From everything I've read over the years there should be one there correct?

05GTO · 09-07-2007, 07:58 PM

You could look on the back of the block behind the #8 cylinder (passenger side) for the casting number, also there should be a 455 on the block by the fuel pump. The casting number for 455's in 73 was 485428 and 490132.