Engine ID question
Thread Starter
Le Mans Master
Joined: May 2004
Posts: 5,866
Likes: 60
From: Hellinois
Finalist 2020 C4 of the Year - Modified
Engine ID question
I don't have a MOTOR manual any more so I am wondering if anyone can tell me what the ID is that's stamped on the pad on the front of the engine block. I'm pulling the engine tomorrow and I have doubts as to it being the original engine. This would be for an 85. Years ago it was two or three letters, that's the only part I need. Thanks.
Burning Brakes
Joined: May 2006
Posts: 857
Likes: 1
From: Morrisonville Illinios
I have a 87 FM and it starts at
H-1987
J-1988
K-1989
L-1990
M-1991
I can't believe that it doesn't go back but maybe you can work the letters back? If you give the pad # i am sure some of the gang can deceipher it out. Good Luck
wro87
H-1987
J-1988
K-1989
L-1990
M-1991
I can't believe that it doesn't go back but maybe you can work the letters back? If you give the pad # i am sure some of the gang can deceipher it out. Good Luck
wro87
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by wro87
I have a 87 FM and it starts at
H-1987
J-1988
K-1989
L-1990
M-1991
H-1987
J-1988
K-1989
L-1990
M-1991
RACE ON!!!
Thread Starter
Le Mans Master
Joined: May 2004
Posts: 5,866
Likes: 60
From: Hellinois
Finalist 2020 C4 of the Year - Modified
Thanks CFI-EFI yes my engine is the original, it ends in ZJJ. Do you remember a few weeks ago we were discussing the fact that my pistons had the four eyebrows instead of one big relief? You felt they weren't original so I got to wondering if my engine was in fact the original or not, well it is the original and I do have the 4 eyebrow pistons, forged, and it is a standard bore so it's highly unlikely they are not the original pistons. Another GM mystery it looks like. Just thought I'd let you know.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
The ZJJ only indicates that the block came from a 1985 Corvette. Does the VIN match? Even though standard, are you sure those four eyebrow pistons are forged, and even if so, original? The parts book only shows one part number per size for 1984/85 pistons. I guess there could have been a style change.
RACE ON!!!
RACE ON!!!
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
pistons
I have taken 3 85 motors apart, and all 3 had 4 eyebrow pistons, so did the two 86 motors, and two 89 motors
none of them were forged, but one 85 motor had wierd smoothed reliefs that look cast in not machined
none of them were forged, but one 85 motor had wierd smoothed reliefs that look cast in not machined
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
The 1986 and 1989 come as no surprise. They are supposed to be cast pistons. Maybe my Genuine Chevrolet Corvette Parts Book is wrong. It shows the 1984 and 1985 as using the same pistons. In fact, the only difference I could find between an '84 and an '85 engine, was the camshaft.
RACE ON!!!
RACE ON!!!
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