So, what is my engine...
Thread Starter
Pro
Joined: Jun 2007
Posts: 634
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From: Hastings MN
So, what is my engine...
18D180990 TO603HN
Do those codes make sense? I was in a dark garage using a flashlight, so I might have mixed up a number or two... but the HN is definitely correct.
Can anyone tell me what this engine is from?
Thanks...
Do those codes make sense? I was in a dark garage using a flashlight, so I might have mixed up a number or two... but the HN is definitely correct.
Can anyone tell me what this engine is from?
Thanks...
Instructor
Joined: May 2006
Posts: 221
Likes: 1
From: Albuquerque New Mexico
Look for the casting number. It is found on the bellhousing flange at the rear of the block. You will see large letters GM and below this will be the casting numbers. with this number it would be easy to tell what you have.
The numbers you provided I guess are most likely from the milled pad at the front of the deck surface, extending just past the cylinder head. these numbers can be changed or faked easily.
The numbers you provided I guess are most likely from the milled pad at the front of the deck surface, extending just past the cylinder head. these numbers can be changed or faked easily.
Last edited by Jc3vette; Jul 3, 2007 at 09:51 PM.
Account disabled by user request 5 Jan 09
Joined: Jan 2005
Posts: 261
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18D180990 = 1968 Atlanta Assembly Plant-Passenger Car-VIN:80,990
T0603HN = Tonawanda, June 3, 1968
HN codes were the following ....
1965 327 Corvette375 L-84 4-spd FI Rochester, HP solid cam
1968 327 Impala 250 L-73 Power glide 4-Brl Hyd Cam
1969 350 Impala 300 L-48 TH 350 4-Brl Hyd Cam
So it looks like a 1968 Impala 327, serial number 80,990, June 3 engine build date in Tonawanda ....
Per ...
Chevrolet by the Numbers, 1965-69, Alan Colvin ... and
http://www.chevymania.com/partsid/su...fm?block=Small
You can confirm this by posting the block casting number and casting date as found on the rear driver and passenger side ...
Last edited by FrankVincent; Jul 3, 2007 at 10:57 PM.
Le Mans Master
Joined: Jan 2003
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From: Tuttle OK
Cruise-In VIII Veteran
more seriously, it's a small block 350. with enough dough and some time you can make some serious HP out of it.
Le Mans Master
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From: Omaha NE
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Heel & Toe
Joined: Jun 2005
Posts: 15
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From: St. Boni MN
Glad I found this thread!
Can anyone tell me where the "J" assembly plant is?
18J302353
Looks like some bastard pulled out our 350hp motor in our 1969 and put in this 327 for an impala in instead...
Can anyone tell me where the "J" assembly plant is?
18J302353
Looks like some bastard pulled out our 350hp motor in our 1969 and put in this 327 for an impala in instead...
Le Mans Master
Joined: Mar 2004
Posts: 7,493
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From: Little Rock AR
Probably a "660" or a "678" block. Large journal 327 block. There isn't anything notable about it. It is just a 2-bolt main 4" bore base engine that is not original to your car. Similar to what was in your car when it was new except the crank has a shorter stroke so you have less displacement and less torque potential.
You can keep it as a 327 or make a 350 or even a 383 with it if you want.
A torquey 383 would proably be my choice for the current application. Your '76 would LOVE it. 
-Mark.
You can keep it as a 327 or make a 350 or even a 383 with it if you want.
A torquey 383 would proably be my choice for the current application. Your '76 would LOVE it. -Mark.
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Joined: May 2005
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From: Millington Illinois
St. Jude Donor '08-'09
Probably a "660" or a "678" block. Large journal 327 block. There isn't anything notable about it. It is just a 2-bolt main 4" bore base engine that is not original to your car. Similar to what was in your car when it was new except the crank has a shorter stroke so you have less displacement and less torque potential.
You can keep it as a 327 or make a 350 or even a 383 with it if you want. A torquey 383 would proably be my choice for the current application. Your '76 would LOVE it.
-Mark.
You can keep it as a 327 or make a 350 or even a 383 with it if you want.
A torquey 383 would proably be my choice for the current application. Your '76 would LOVE it. -Mark.
Built a 383 for my vette too. But a solid lifter 327 or even 302 is a lot of fun. Had a solid lifter 302 that started really pulling at 4000. It was still pulling good at 8000 rpm and felt like there was more RPM capability there.
Heel & Toe
Joined: Jun 2005
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From: St. Boni MN
