1970 Chevelle SS Engine Codes and Production Numbers
April 22nd, 2011 by Road Test TV
Engine Code Cu. In. & RPO Transmission
CKO 402-4 375-L78 4 speed manual
CKP 402-4 375-L78 (w/L89) TH-400
CKQ 402-4 375-L78 Manual-3/4 HD Clutch
CKT 402-4 375-L78 (w/L89) Manual-3/4 speed
CKU 402-4 375-L78 (w/L89) Manual-3/4 HD Clutch
CTW 402-4 350-L34 TH-400
CTX 402-4 350-L34 Manual-3/4 speed
CTY 402-4 375-L78 TH-400
CTZ 402-4 350-L34 Manual-3/4 speed HD Clutch
CRQ 454-4 360-LS5 TH-400
CRR 454-4 450-LS6 TH-400
CRS (1) 454-4 450-LS6(w/L89) TH-400
CRT 454-4 360-LS5 4 speed manual M22
CRU 454-4 360-LS5 4 speed manual M22 Heavy Duty Clutch
CRV 454-4 450-LS6 4 speed manual M22
CRX 454-4 450-LS6 4 speed manual M22/HD Clutch
CRY (1) 454-4 450-LS6(w/L89) 4 speed M22/HD Clutch
L89 – designates Aluminum Head Option
(1) In 1970 there is a dispute as to whether any 454 LS6s where equipped with aluminum heads. A respected source contends that no 454 were built with aluminum heads according Tonawanda records. According to said source, Tonawanda records indicate the L89 (aluminum head) option was cancelled and not replaced at the end of L78 production in November of 1969.
However, some have reported that the CRS (aluminum head) code has appeared on engine blocks. It is also reported that one individual has a warranty protect-o-plate card showing the CRY code.
These figures are for the U.S. production of Chevelles only (unless otherwise indicated) and does not include the Monte Carlo.
A total of 39,207 6-cyl engines were installed; 29,791 in U.S. built Chevelles and 10,416 imported from Canada.
A total of 413,255 8-cyl engines were installed; 198,285 307cid, 150,745 350cid, and 64,225 402/454cid engines.
GM of Canada documents establish that 3,306 Z25 (SS396) and 299 Z15 (SS454 – LS5 only) optioned Chevelle Sport Coupes were exported for sale to the U.S.
Total 1970 Chevelle SuperSport Production numbers:
53,599 – Z25 SS396 options ordered (51,455 base L34 plus 2,144 optional RPO L78)
8,773 – Z15 SS454 options ordered (4,298 base LS5 plus 4,475 optional RPO LS6)
Chevrolet only reports 442,046 engines and transmissions on the Accumulative Production Report of August 31, 1970. This number is only for U.S. built Chevelles. There is no breakdown of engines or transmissions imported from Canada.