Unknown engine
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6th Gear
Joined: Aug 2024
Posts: 6
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Unknown engine
Need some help identifying an engine
Casting # 1 GM 3970010 Mexico?
FWD pass head N5626793 MF028(0P)(0W)?
No where i look explains why the 00 at the end has PW inside the 0's.
From what i can look up it may be a 327 or 350?
Files attached as PDF's couldn't get jpegs to attach for some reason.
Casting # 1 GM 3970010 Mexico?
FWD pass head N5626793 MF028(0P)(0W)?
No where i look explains why the 00 at the end has PW inside the 0's.
From what i can look up it may be a 327 or 350?
Files attached as PDF's couldn't get jpegs to attach for some reason.
Race Director
Joined: Nov 2006
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From: Sunshine Coast, Queensland, Australia
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And you purchased this engine where? And you installed it in what car, when??
Melting Slicks
Joined: Nov 2006
Posts: 3,410
Likes: 1,821
From: Apple Valley, MN
The 3970010 block was used in many applications beyond the Corvette. Blocks cast in Mexico have the “made in Mexico” cast above the number.
The “head casting picture” is not of a head, but the front pad of the block. The MF code is not associated with a Corvette.
Nothing special about it.
The “head casting picture” is not of a head, but the front pad of the block. The MF code is not associated with a Corvette.
Nothing special about it.
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Joined: Oct 2000
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From: Shamong, NJ
It sounds like it might be a late 70's GM Targetmaster 350. I forget how to decode them and I don't have an 80's parts book nearby but I think the "M" was Mexico engine plant, "F" was June and "02" was the second of the month. They are always identifiable by the "Hecko en Mexico" cast into the rear of the block. I think the number "86" is often found cast into the back of the block too.
The Targetmaster 350 crate engine was released by Chevrolet in the late 70's. They were brand new engines based on the L-48 350, and made in Mexico that sold for $1000 or less. The Targetmaster was a complete engine less water pump, intake, carb, and distributor, with 4 bolt mains, 2 piece rear main seal, a compression ratio of about 8.5, and the L-48 cam and 76CC combustion chamber heads. It was originally released as a cheap replacement engine for commercial applications (light trucks), but quickly became popular as a replacement engine for just about anything that had a small block in it. In the late 80's it was replaced by the nearly identical Goodwrench 350 crate engine.
The Targetmaster 350 crate engine was released by Chevrolet in the late 70's. They were brand new engines based on the L-48 350, and made in Mexico that sold for $1000 or less. The Targetmaster was a complete engine less water pump, intake, carb, and distributor, with 4 bolt mains, 2 piece rear main seal, a compression ratio of about 8.5, and the L-48 cam and 76CC combustion chamber heads. It was originally released as a cheap replacement engine for commercial applications (light trucks), but quickly became popular as a replacement engine for just about anything that had a small block in it. In the late 80's it was replaced by the nearly identical Goodwrench 350 crate engine.