Block ID
Melting Slicks
Joined: May 2002
Posts: 2,476
Likes: 756
From: Laporte, IN
Suffix code CHC was used in a Corvette in 1975,76 and 1980 not in a 1978.
1978 codes were:
CHW
CLR
CLM
CLS
CMR
CMS
CUT
VIN should be 18S4XXXXX or 18S9XXXXX
Total 1978 production was 46,776 units. Your block VIN is 81222 unit number
1978 codes were:
CHW
CLR
CLM
CLS
CMR
CMS
CUT
VIN should be 18S4XXXXX or 18S9XXXXX
Total 1978 production was 46,776 units. Your block VIN is 81222 unit number
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,391
From: At my Bar drinking and wrenching in Lafayette Colorado
CHC engines were used and designated as follows:
- 1973 307 (115 hp) Chevelle & Nova, 2-barrel, California emissions, automatic
- 1975 350 (205 hp) Corvette 4-barrel, 4-speed
- 1976 350 (210 hp) Corvette 4-barrel, 4-speed
- 1978 350 (170 hp) Camaro 4-barrel, Turbo 350 automatic
- 1988 305 (220 hp) Camaro Automatic transmission, Tuned Port Injection
Lars
Last edited by lars; May 22, 2021 at 11:59 AM.
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Le Mans Master
Joined: Mar 2004
Posts: 7,502
Likes: 1,509
From: Little Rock AR
You know it is a 350. You know it is not a 305 or 400.
It probably does not have pushrod guideplates on the heads so it is not an L-82 so......it is a base 350. You could look inside the oil pan with an endoscope to see if it has 4 bolt mains or a windage tray but my money is on 2 bolt mains, cast iron crank and no windage tray. Crankshaft should be visible at back of block so you can see the casting parting line. They all have the same cam and small valve heads. Not much else is in there.
It probably does not have pushrod guideplates on the heads so it is not an L-82 so......it is a base 350. You could look inside the oil pan with an endoscope to see if it has 4 bolt mains or a windage tray but my money is on 2 bolt mains, cast iron crank and no windage tray. Crankshaft should be visible at back of block so you can see the casting parting line. They all have the same cam and small valve heads. Not much else is in there.
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,482
From: Southbound
Cruise-In II Veteran