27.720 Corvettes were built in 1966. 9.958 Coupe and 17.762 Convertibles.
The Vehicle Identification Numbers, VIN were 194376S100001 through 194376S127720
For convertibles, fourth digit is a 6

Type Basic Basic Basic Basic
Cubic Inch 327 327 427  427
HP @ RPM 300 @ 5000 350 @ 5800 390 @ 5200 425 @ 5600
Torque  RPM 360 @ 3200 360 @ 3600 460 @ 3600 460 @ 4000
Comp. Ratio 10.5:1 11.0:1 10.25:1 11.0:1
Bore / Stroke 4.00 x 3.25 4.00 x 3.25 4.25 x 3.76 4.25 x 3.76
Carburator 4bbl Holley 4bbl Holley  4bbl Holley 4bbl Holley 
In Manifold N/A N/A N/A N/A
Valve Lifters N/A N/A N/A N/A
Exhaust N/A N/A N/A N/A
Oil Capacity2 4 Qt 4 Qt 5 QT 5 QT
Spark Plugs Type 44 Type 44 Type 43N Type 43N
2. Add 1 Qt if you put a new oil filter.

3858174 327 CID
3892657 327 CID - Late production
3869942 427 CID
3855961 427 CID - Early production

3782461 327 CID - 300 HP / 350 HP
3873858 427 CID - 425 HP / 450 HP
3872702 427 CID - 390 HP

327 Cubic Inch Engine CODE
350 HP - Manual transmission - Air injection HD
300 HP - Manual transmission HE
300 HP - Manual transmission - Air injection HH
300 HP - Automatic transmission HO
350 HP - Manual transmission - Power steering HP
300 HP - Automatic transmission - Air injection HR
350 HP - Manual transmission HT
350 HP - Manual transmission - Air injection - Air condition - Power steering KH
427 Cubic Inch Engine CODE
425 HP - Manual transmission IK
390 HP - Manual transmission IL
390 HP - Manual transmission - Air injection IM
425 HP / 450 HP - Manual transmission IP
390 HP - Automatic transmission IQ
390 HP - Automatic transmission - Air injection IR

Ratio and Type CODE
3.36 AK
3.08 Positraction AL
3.36 Positraction AM
3.55 Positraction AN
3.70 Positraction AO
4.11 Positraction AP
3.08 Positraction AR
3.70 with 4-speed AS
3.08 Positraction with 427 CID AT
3.36 Positraction with 427 CID AU
3.55 Positraction with 427 CID AZ
3.70 Positraction with 427 CID FA
4.11 Positraction with 427 CID FB
4.56 Positraction with 427 CID FC

Color CODE
Tuxedo Black 900
Ermine White 972
Rally Red 974
Nassau Blue 976
Laguna Blue 978
Trophy Blue 980
Mosport Green 982
Sunfire Yellow 984
Silver Pearl 986
Milano Maroon 988

Tommy Ledberg