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While primarily intended for the
Chevrolet Vega, the H platform was not developed by the Chevrolet Division itself, but became the first vehicle architecture developed by a centralized GM design and engineering team. Replacing two subcompact cars separately in development by Chevrolet and Pontiac,
530:
For 1975, the introduction of the
Chevrolet Monza saw the introduction of V8 engines to H platform (not offered in the Vega and Astre). In 1975, the H-platform also adopted a Buick-designed 231 cubic-inch V6. For 1978, the 140 cubic-inch inline-4 was replaced by a Pontiac-designed 151 cubic-inch
507:
For 1975, the
Chevrolet Monza was introduced as a three-door hatchback, alongside the Buick Skyhawk, and Oldsmobile Starfire; a two-door notchback coupe was introduced during the model year. For 1976, the Pontiac Sunbird was introduced, sharing the body of the Monza notchback coupe; a Sunbird
466:
development of the H-body began in 1968. In slightly over two years, GM sought to develop its first subcompact with a sub-2000 pound curb weight, an all-aluminum engine, and priced at or less than the
Volkswagen Beetle; assembly of the vehicle was to be primarily automated.
500:
For 1971, the
Chevrolet Vega was introduced in four body styles, including a two-door sedan, a three-door hatchback and a three-door station wagon and panel delivery. For 1973, the front bumper was relocated forward; for 1974, both front bumpers were redesigned.
484:
The unibody H-platform is rear-wheel drive, using a 97-inch wheelbase. Scaling down the design of larger GM platforms, the H platform uses unequal-length A-arm front suspension; the rear suspension is a coil-spring solid rear axle.
538:
In addition to the
Cosworth Vega engine, the H platform served in the development of several advanced GM engine designs. In 1972, a prototype Vega powered by a 302 cubic-inch aluminum-block V8 (derived from
519:
The
Chevrolet Vega was introduced with a Chevrolet-designed 140 cubic-inch inline-4 engine; while using an aluminum engine block, the cylinder head was of cast-iron construction. The later
547:
was intended to be a key feature of the
Chevrolet Monza hatchback and its counterparts; following its 1974 cancellation, the GMRCA was replaced by 262 and 305 cubic-inch Chevrolet V8s.
504:
The
Pontiac Astre was introduced for 1973, styled with a different front grille from the Vega. Initially exclusive to Canada, Pontiac released the Astre in the United States for 1975.
896:
725:
511:
For 1978, the Vega and Astre were discontinued, with the station wagon body style rebadged as a Monza and
Sunbird wagon; the station wagon was dropped for 1980.
917:
450:
compacts to front-wheel drive, the H platform ended production for the 1980 model year. For 1982, the H-body vehicles were replaced by the front-wheel drive
544:
457:
From 1986 to 1999, the H platform designation was revived for front-wheel drive full-size sedans of the Buick, Oldsmobile, and Pontiac divisions.
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from the 1971 to 1980 model years. The first subcompact car design developed by GM, the rear-wheel drive H platform initially underpinned the
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used dual overhead camshafts, 4 valves per cylinder, and electronic fuel injection; in total, 5000 engines were assembled for 1975.
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personal luxury), GM moved to redesign the rest of its major model lines. Following the 1980 shift of the
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hatchback was introduced during 1976 (the Skyhawk and Starfire were only offered as hatchbacks).
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was fitted with a 122 cubic-inch all-aluminum inline-4. An advanced design for the time, the
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427:(later sold alongside it), the H-platform was sold nearly exclusively in North America.
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726:"Did the Chevrolet Vega develop out of stalled plans for a third-generation Corvair?"
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counterpart. For 1975, the H platform was expanded from entry-level vehicles to
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754:"Chevrolet Vega: A Terrible Car That Shouldn't Have Been Terrible"
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The fourth character in the Vehicle Identification Number
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818:Chevrolet Cosworth Vega press release-March 1975
830:The Standard Catalog of American Cars 1946–1975
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8:
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784:Huffman, John Pearley (October 19, 2010).
52:
43:
809:Vega Shop Manual-Chevrolet Motor Division
554:
716:
423:In contrast to the globally-developed
307:350 cu in (5.7 L) OHV
302:305 cu in (5.0 L) OHV
297:262 cu in (4.3 L) OHV
292:231 cu in (3.8 L) OHV
287:196 cu in (3.2 L) OHV
7:
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870:H-body.se - Swedish H-Body registry
786:"The Car That Nearly Destroyed GM"
25:
279:151 cu in (2.5 L)
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478:H platform component arrangement
339:Turbo-Hydramatic 3 spd.automatic
724:Strohl, Daniel (May 26, 2021).
332:Torque-Drive clutchless manual
1:
531:inline-4 (later known as the
434:of its larger car lines (the
355:97.0 in (2,464 mm)
828:Gunnell, John, ed. (1987).
583:97.0 in (2464 mm)
335:Powerglide 2 spd. automatic
1483:
852:Hot Rod magazine-July 1972
492:for an H-body car is "H".
72:General Motors Corporation
34:
26:
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924:
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369:General Motors J platform
51:
1467:General Motors platforms
681:Chevrolet Cosworth Vega
521:Chevrolet Cosworth Vega
114:Sainte-Thérèse Assembly
832:. Kraus Publications.
481:
120:Ramos Arizpe, Coahuila
100:South Gate, California
41:Motor vehicle platform
477:
168:2-door fastback coupe
946:Delta (D2XX/PATAC K)
760:. September 18, 2020
525:Cosworth Vega engine
29:List of GM platforms
966:Epsilon (E2XX/P2XX)
706:Oldsmobile Starfire
658:Oldsmobile Starfire
414:Oldsmobile Starfire
386:automobile platform
376:The General Motors
215:Oldsmobile Starfire
104:South Gate Assembly
18:GM H platform (RWD)
567:Previous platform
533:"Iron Duke" engine
515:Powertrain details
482:
95:Lordstown Assembly
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790:Popular Mechanics
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327:5-speed manual w/
16:(Redirected from
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126:Body and chassis
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696:Pontiac Sunbird
691:Chevrolet Monza
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624:Pontiac Sunbird
610:Chevrolet Monza
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470:Design overview
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418:Pontiac Sunbird
406:Chevrolet Monza
390:subcompact cars
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316:Transmission(s)
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220:Pontiac Sunbird
205:Chevrolet Monza
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91:Lordstown, Ohio
89:United States:
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859:External links
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676:Chevrolet Vega
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579:Chevrolet Vega
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570:Next platform
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442:intermediate,
430:Following the
402:sport compacts
394:Chevrolet Vega
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325:4-speed manual
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195:Chevrolet Vega
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182:panel delivery
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110:Quebec, Canada
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35:Main article:
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927:In production
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839:0-87341-096-3
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701:Buick Skyhawk
699:
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686:Pontiac Astre
684:
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648:GM J platform
646:
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641:Buick Skyhawk
639:
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631:GM J platform
629:
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596:Pontiac Astre
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410:Buick Skyhawk
407:
404:, adding the
403:
399:
398:Pontiac Astre
395:
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210:Buick Skyhawk
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200:Pontiac Astre
198:
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186:
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159:
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156:Body style(s)
153:
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38:
37:GM H platform
33:
30:
19:
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1035:
926:
848:
829:
823:
814:
805:
793:. Retrieved
789:
762:. Retrieved
757:
733:. Retrieved
729:
719:
537:
529:
518:
510:
506:
503:
499:
487:
483:
464:
456:
429:
422:
381:
377:
375:
67:Manufacturer
32:
1396:Trucks/SUVs
1299:Trucks/SUVs
990:Trucks/SUVs
496:Body design
461:Development
438:full-size,
78:Also called
1306:C/K Series
865:H-Body.Org
758:MotorTrend
712:References
564:Wheelbase
480:Vega Sedan
432:downsizing
425:T platform
378:H platform
360:Chronology
345:Dimensions
229:Powertrain
137:Subcompact
47:H-platform
27:See also:
909:platforms
654:1975–1980
637:1975–1980
620:1976–1980
606:1975–1980
592:1973–1977
575:1971–1977
365:Successor
351:Wheelbase
329:overdrive
267:2.0 Liter
255:2.3 Liter
241:2.3 Liter
235:Engine(s)
172:hatchback
162:notchback
149:FR layout
1461:Category
1426:Category
795:July 19,
764:July 19,
735:July 19,
730:Hemmings
670:See also
396:and its
388:used by
384:) is an
320:3-speed
265:122 CID
253:140 CID
239:140 CID
188:Vehicles
180:3- door
175:3- door
118:Mexico:
108:Canada:
86:Assembly
61:Overview
1436:Commons
1335:530/560
1319:345/745
1315:325/330
1208:Premium
1036:Retired
918:Marques
545:(GMRCA)
170:3-door
160:2-door
1373:Future
1357:Lambda
1122:GM4200
1117:GM2900
836:
561:Model
558:Years
551:Models
541:CERV I
452:J-body
448:X-body
444:E-body
440:A-body
436:B-body
416:, and
382:H-body
322:manual
144:Layout
81:H-body
1408:VSS-T
1403:VSS-S
1387:VSS-R
1362:Theta
1228:Sigma
1165:Kappa
976:Omega
971:Alpha
961:VSS-F
941:Gamma
490:(VIN)
177:wagon
165:coupe
132:Class
1446:List
1380:Cars
1351:K2XX
1290:Zeta
1223:SCCS
1069:BEV2
1043:Cars
1019:T1XX
1011:31XX
1002:C1XX
951:BEV3
934:Cars
834:ISBN
797:2021
766:2021
737:2021
380:(or
270:DOHC
259:2bbl
257:OHC
247:1bbl
1347:900
1343:800
1339:600
1331:400
1327:360
1323:355
1311:GMT
1274:RWD
1270:FWD
1255:RWD
1251:FWD
1241:RWD
1237:FWD
1202:FWD
1198:RWD
1183:RWD
1179:FWD
1159:RWD
1155:FWD
1135:RWD
1131:FWD
1111:RWD
1107:FWD
1082:RWD
1078:FWD
1058:RWD
1054:FWD
1015:610
1007:GMT
997:BT1
956:GEM
535:).
281:OHV
273:EFI
244:OHC
1463::
1349:,
1345:,
1341:,
1337:,
1333:,
1329:,
1325:,
1321:,
1317:,
1272:,
1253:,
1239:,
1200:,
1181:,
1157:,
1141:HQ
1133:,
1109:,
1080:,
1056:,
1017:,
1013:,
788:.
774:^
756:.
745:^
728:.
420:.
412:,
408:,
309:V8
304:V8
299:V8
294:V6
289:V6
284:I4
276:I4
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1285:Z
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1175:M
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1103:G
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