1966 pontiac 421 engine specs 1966 pontiac 421 engine specs

A larger 4in (101.6mm) ram air flex duct to the air cleaner from the left-hand fender, specific carburettor calibration for the Rochester Quadrajet, a "T/A 4.9" callout on the shaker, 60 psi oil pump, and cam similar in grind to the 220hp (164kW) 400 from the 19781979 model year were also included. The engines feature a cast-iron block and head and two valves per cylinder. By comparison, the factory 421 H.O. Ellingson Motorcars (877) 638-7170. A 400 cubic inch ram air equipped V8, it was an option on the 1969-70 GTO and Firebird Formula. An example of data being processed may be a unique identifier stored in a cookie. Car and Driver magazine, which had showcased the infamous Pontiac GTO vs. Ferrari's GTO comparison in 1964, organized another bout between the . All Rights Reserved. Lobe separation angle: 112-deg All 428 cylinder heads received the 14 degree valve angle, closed chamber only in 67 and open chamber 68 and up. Headers: Hooker Super Comp (for dyno test) Engine displacement is a function of bore and stroke. Pontiac Engine Torque Specs Pontiac Engine Torque Specs. The 400 remained in production through the 1978 model year, with 1979 cars receiving engines produced the previous year. Despite their work, the division's conservative management saw no immediate need to replace the Pontiac Straight-8 until later in the 1950s. The SD-389 was limited to a single 4-barrel while the SD-421 used dual 4-barrels. With higher compression and dual exhaust it produced 280hp (209kW) for 19631964, and 285hp (213kW) for 1965 through 1967, its final year. Regarding Crower's upgrade suggestions for its camshaft, Jim pretty much has it covered. Rings: LPC (Liberty Performance Components) premium moly, standard tension As a result, peak horsepower dropped from 310 to 290, though torque increased from 390 to 395lb. The 1979 W72/WS6 equipped Trans Am was considered to be one of the overall best performing cars of the decade due to having a powerplant that produced more power than any other competitor on the market at the time with handling equipment to supplement the performance.[12]. Like the 421, the 428 used a large-journal crankshaft, but externally it was the same size as all Pontiac V-8s of that era (the later 301 used a shorter deck height). Email Email. The 1955-up Pontiac V8 that finally reached the public was an overhead valve engine with cast iron cylinder heads and block and wedge-shaped combustion chambers. 1963 Pontiac V8 Engine Specs. [19], Parts for Ram Air V engines are not readily available. The 389 would remain the standard Pontiac V8 engine through 1966, offered in a bewildering variety of outputs ranging from 215 to 368hp (160 to 274kW). Pontiac V8 Engine Codes and Specifications. A period-correct battery cranks the high-compression 469-cubic-inch Pontiac engine. The 400 HO was offered as an option for 1967-1970 for GTO and 1968-1970 for Firebird. Windage tray: Original PMD '70 455, fabricate fit, no bosses at cap #2 The Ram Air IV also used a lightweight aluminum intake-manifold that produced a weight savings of 1015lb (4.56.8kg). The new-for-1965 "Venturi" body shape and curved side glass were carried over with updates front and rear. Whether all were installed in GTOs is unknown. Factory heavy-duty high-pressure oil pump and eight-quart sump, four-bolt main bearing caps with Moraine aluminum bearings, and #1110976 dual-point distributor without vacuum advance. There are no manual transmission equipped Trans Ams that came factory with the standard L78 400 motor in 1977-79. [2] This was the engine installed in the Pontiac Executive line of large cars[3] and its largest station wagon, the Pontiac Safari. See Consumer Guide Automotive's New-Car Reviews, Prices, and Information. Information and specs for the Pontiac 421 V8 engine. Cam choice is always extremely important, and Jim decided to go with an aggressive Crower mechanical flat-tappet stick with 247/252-degrees duration at 0.050 and 0.515/0.525 lift (0.495/0.505 with 0.020 lash) with 1.6:1 rockers. Intake: 218 cfm at 0.500-in The Pontiac V8 engine is a family of overhead valve 90 V8 engines manufactured by the Pontiac Division of General Motors Corporation between 1955 and 1981. Length: 8.750-inCAM The results showed Pontiac that an L-head simply couldn't compete with an overhead valve engine. Various Pontiac sources have emphatically stated that NO 310hp (231kW) versions of the SD-455 were installed in regular production cars. Reductions in reciprocating weight free up horsepower. Pontiac V8 Engine Tune Up Specifications. It requires a compression ratio of at least 10.25:1. 1965 Pontiac LeMans GTO Mecum. However, the 1959 389 engines had the generator in front of the heads with reverse flow cooling still in use. In 1968, a 320hp (239kW) HO option was offered in the Tempest and Firebird. Along with a cam swap it boosted horsepower from 325 hp with the four-barrel carb to 348 hp in '64. [5] It was rated at 360hp (268kW), but the Grand Prix with the same specifications was rated at 370hp (276kW).[6]. Mods: Built to factory specifications/ adapt '64 choke to '66 center carburetor Collector size: 3.00-inGASKETS This included the ESC (Electronic Spark Control) distributor and controller borrowed from the 301 Turbo, which allowed for higher timing without the penalty of engine damaging pinging or preignition. Total Timing: 36-deg BTDC Still, it was the strongest American engine offered that year. [8] All of these improvements provided the W72 with a power rating of 200hp (203PS; 149kW) at 3600 rpm and 325lbft (441Nm) of torque at 2400 rpm, while the standard L78 400 only produced 180hp (182PS; 134kW) at 3600 rpm and 325lbft (441Nm) of torque at 1600 rpm. 1967 - 400 Ram Air or 428 Code 670. The Ram Air IV used the Ram Air II's camshaft but lift in the Ram Air IV was increased to 0.52in (13mm) thanks to the use of 1.65 ratio rocker arms (vs 1.50). Made with a provision for dry sump oiling, it truly was a racing engine, detuned for use in passenger cars. According to the June 2019 issue of Muscle car Review magazine, during dyno testing performed during that era, the National Hot Rod Association (NHRA) rated this Pontiac W72 400 T/A 6.6 engine at 260 to 280 net horsepower instead of the 220-hp rating published by Pontiac. Valve lift stayed at just over 0.400-inch with 1.5:1-ratio rocker arms. For the 1978 model year, Pontiac re-incorporated the earlier thicker cast cast engine block denoted by the cast number 418988 and a "XX" cast into the side of the block. 3.75. Primary tube length: approximately 31.00 inches Along with proper parts selection, accurate machining and assembly are also important Year: CU IN: Casting # 1967: 326. Diameter: 516-in Free local pickup. Kits for Pontiac applications. In 1968 the 326 was replaced by the similarly 389-derived 350, which used a 3+78in (98.4mm) bore and 3+34in (95.3mm) stroke for a total displacement of 353.8cuin (5,798cc). Two four-barrel carburetors, 10.5:1 compression, 285hp (213kW) @ 5100rpm, 330lbft (447Nm) @ 2600rpm. By 1979, Pontiac was no longer allowed to produce the 400 engine as emissions further tightened. Bore/Stroke: 4.150/4.00-in The most famous S/D of them all. Keepers: Comp Cams race locks The inlets were all well within the boundary layer that exists close to the surface, so all of these systems would more accurately be described as "outside air induction" systems, benefiting from the intake of cooler, and thus denser, outside air versus the comparatively hotter and less dense air under the car's hood. Model Number: Body/Style Number: Body Type & Seating: Factory Price: . In 1967, the Pontiac 2+2 became an option on the . Two tri-power 421s were optional, one with 356 bhp, the other with 376. Not long before the model year introduction, Pontiac management decided that the entire line would be V8-powered. From 1969 though 1970, the Ram Air IV was available in both A-Body (GTO, including Judge) and F-body (Firebird, including Trans Am) form. Preparation: File-fit for end gap if needed, wash The last was the 421 HO and included a high-output camshaft and valve train. The camshaft was the HO cam with 288/301 duration. Released in 1961, the 421 was a bored and stroked 389 which sported a bore of 4.094 and a stroke of 4.00. Distributor: '61 Delco cast-iron with direct oiling It shared the 4.121in (104.7mm) bore of the 400, but with a 2.84in (72.1mm) stroke for a displacement of 303cuin (5.0L). It was rated 180hp (134kW) @ 4600rpm and 264lbft (358Nm) @ 2400rpm with a two-barrel carburetor, 200hp (149kW) @ 4600rpm and 278lbft (377Nm) @ 2800rpm with the four-barrel carburetor. The code consists of 3 or 4 digits. ENGINE TYPE Water-cooled V-8, cast iron block and head Displacement 428 in 3, 7015 cm 3 Power 390 hp @ 5200 rpm On premium fuel, it was rated at 207 hp at 5200 rpm and . To view the purposes they believe they have legitimate interest for, or to object to this data processing use the vendor list link below. The 4-barrel version was available from 1978 to 1981 and the Turbo version was limited to the 1980 and 1981 model year, however, it was originally intended to be available for the 3rd generation Firebird before its cancellation by GM. 1966 Pontiac Catalina Specifications and Production. in. If you've been thinking about cruising the local boulevard in a classy convertible, but find yourself longing for the power under the hood that only a muscle car provides, perhaps it's time to take another long look at Pontiac's restyled 1965 Bonneville convertible. ][citation needed] T, While the exact total number of Ram Air V engines produced is not positively known, only about 25 303cuin (5.0L) engines were produced and about a dozen 428s and 366s. Only 157 Ram Air IV Firebirds, including 55 Trans Ams, were built for 1969. Pontiac introduced the OHC 6 in two flavors for '66: a base engine with a one-barrel carburetor that developed 165 hp at 4700 rpm, and a sportier version with a 10.5:1 compression ratio, a high-lift cam, a split exhaust manifold, and GM's new four-barrel Quadrajet carburetor (below). Bore and stroke were 4.121in 2.84in (104.7mm 72.1mm) 303.63cuin (4,976cc). - P.B. Preparation: Wash after balance for assembly Manage Settings 1967 was the last year for closed-chambered heads. Based in part on designs for the "short deck" 303cuin (5.0L) engine designed for the 1970 racing season, it had a shorter deck than the big V8, and used thin-wall castings to reduce weight. Initial advance: 18-deg To learn everything you need to know about car engines, see. Oil pump: . . Most Pontiac engines like total timing (rev engine past 3000 or so until the mechanical advance stops moving/advancing, vacuum advance disconnected to check total timing) somewhere between 32 and 36 degrees. Math, not gasoline, makes horsepower under the hood of a Pontiac. Where else will the extra 100 horses come from? For those who may not be familiar with the equation, here it is again: The 338-bhp four-barrel was the base engine. Casting No. By comparison, the factory 421 H.O. Centerline: 110-deg Casting number: 97770716, '64 date Two different cylinder-head castings were used for the 1962 model year, both with a combustion chamber volume of 68cc (4.15cuin) to produce an 11.0:1 compression ratio. Engine block and cylinder heads were cast at Saginaw Metal Casting Operations then assembled at Tonawanda Engine before delivery to Pontiac Assembly for installation. Primary tube diameter: 1.75-in An HO version could be ordered in the GTO, as GM had lifted its restrictions on offering engines larger than 400cuin (6.6L) in mid-sized cars (resulting in the 454 (7.44) Chevrolet Chevelle, / 8.3 mpg (U.S.) / 3.5 km/l, more data: 1966 Pontiac Bonneville Convertible . in. The rod weighs 751 grams versus the stock rod at 958 grams. The 389 V8 was first introduced by Pontiac in 1959. Unfortunately, there were no improvements in the casting number "01" small-valve high-velocity heads, which would have yielded greater improvements in power. The stroke increased to 4.21-inch (106.9mm). This 356hp monster is backed by a 4-speed manual transmission, while the Pontiac also features power steering and power brakes. It could only be ordered with a TH200 automatic transmission and a 2bbl configuration. The 421 engine is available only with related heavy-duty driveline components. Royal Pontiac developed the prototype of the package on their 1965 GTO drag car and Pontiac picked up the idea and in August 1965 Pontiac offered the new Fresh Air package to dealers consisting of the parts and instructions needed to make the hood scoop functional, including the metal tub to mount to the carburetors and rubber gasket to seal it to the underside of the hood. However, the engine used in these Trans Ams was the same regular production 455 taken from the big body cars Pontiac was producing, and output 200 HP with a torque rating of 330lbft at 2,000 rpm.[13]. Engine Year Info Spark Plug Plug Gap Point Gap Dwell Angle Timing (BTDC) Idel RPM Manual Tran. Maximum flow at 28 inches of water This had extra-rich "DX" secondary metering rods and a remote vacuum source for the primary metering rod enrichment circuit to allow the Power Enrichment Vacuum Regulator (PEVR) to release the primary metering rods to move to the up position (enrichment) anytime during boosted conditions. Based on the same short-deck as the 301, the "LS5" 265.1cuin (4.3L) was offered only in 1980 and 1981. The L75 455 engine continued as an option into the 1976 model year for the Trans Am, however, Pontiac opted to drop the "H.O." The 2+2 reverted to option status for '67, then died, a proud relic of a time when big cars, Pontiacs in particular, ruled the streets. and so the 326 bore size was reduced to 3.72in (94.5mm), giving a true 326.06cuin (5.3L). Rods: Howard's billet 4340 certified steel, stock 6.625-in, floating pins The basic package included the heavy-duty suspension, with even stiffer springs and shocks available. Open pressure: 282 pounds at 1.100-in in., again available only in the GTO and Firebird. A Pontiac SD 421 came with forged steel rods and crankshafts for extra durability. The engines feature a cast-iron block and head and two valves per cylinder. It also sports the four-speed manual, limited . The 389 was the standard engine on the GTO up to 1966. On the invoicing for the 1979 model year Firebirds, they had the option listed as L78, however, every 1979 400 equipped car received a W72 engine. The 301T block was significantly more durable than the standard 301 block and received a thicker bottom end. This was the beginning of factory supplied performance items such as 4 bolt main bearings and windage trays to reduce friction from crankcase oil. Cam was a #541596 McKellar No. Some production test cars ran considerably slower and yielded 14-mile (402m) times in the 14.5 second/98mph (158km/h) range in showroom tune (uncited sources)- results that are quite consistent for a car with a curb weight of 3,850 pounds (1,746kg) and the rated 290hp (216kW) SAE NET figure that some sources suggest was "under-rated." Along with being cheaper to build, this allowed more consistent valve action with less weight than a conventional shaft. Power output ranged from 135hp (101kW) to 170hp (127kW). For the 1967 GTO the engine was rated at 360bhp (268kW; 365PS) and had the cast-iron headers. It used a declutching fan, special exhaust manifolds, and chrome low-restriction air cleaners; rocker covers and oil-filler cap also were chrome. 455 (7.5) Buick Gran Sport, and 455 (7.5) Oldsmobile 442). RamAir 4 Motor Price $15500.00. Crower identifies this cam as a Level 4, which means it provides strong midrange and top-end power for heavily modified engines. 1962 Pontiac Catalina, Royal Bobcat Super Duty 421. To learn about it, read. In the early '60s, the engine program at the Pontiac division of General Motors was a wide-open operation that bustled with innovation. The 1971 Pontiac 455 HO was Pontiac's first engine to receive a special 800cuft/min (23m3/min) Rochester Quadra-jet carburetor with specific jetting. It is probably best known for it's Tri-power option, which was optional on GTO's from 1964 through 1966.. A higher-output four-barrel carburetor version was offered, called the 326 HO (High Output). The 1966 Pontiac Ventura doesn't necessarily come up when speaking of 60's muscle cars, but the type of V-8's offered with the Ventura meant plenty of power. Next time we will cover the induction system and the dyno testing to see if Jim meets his goal. In 1977 the 400-cubic-inch (6.6L) T/A 6.6, (RPO code W72) was created to fulfil the performance engine gap in the Pontiac line-up. Also added was the #48 casting number heads with a 68cc (4.15cuin) chamber for higher compression, along with larger 2.11 and 1.77in (54 and 45mm) valves. This was the last run for the 455 (7.5 L) motor from Pontiac, and production ceased on the 455 this year as it could no longer meet the emissions requirements any longer. Most likely prompted by its development of the Pontiac OHC six, the GM division built three different experimental SOHC 421 CID V8 engines in the early 1960s. Crank: Original '64 421 Duration at .050: 247/252-deg Preparation: Disassemble, check ball seat for width, spring tension, plate clearanceHEADS In 1969 the 350 HO was upgraded again with the addition of the 400 HO cam, commonly referred to by enthusiasts as the 068 cam. 1966: 421: 9782611 (late) 1967-1969. . Specifications listing with the performance factory . The 303 had shorter connecting rods, smaller 2.5in (64mm) journals and a solid lifter version of the Ram Air IV camshaft. Valve seals: U.S. Seal The GTO's new hood scoop design, with the inlets centrally located and mounted above the carburetor, provided the opportunity for experimentation. A total of 1,808 Ram Air IV production cars were built over its 2-year production. The 326 subsequently became the optional V8 engine for Tempests, and later the Pontiac Firebird, through 1967 and maintained the 17 degree cylinder head valve angle for its entire production run. Calling into play enormous power and a decent 55/45 weight distribution, the 2+2 could be launched with little tire spin and guided through corners with alarming efficiency. aluminum V8 it had offered in the Tempest and replaced it with a small-bore version of the standard 389cuin (6.4L) Pontiac V8. The SD-455 used round-port cylinder heads similar to those used on the 1971 and 1972 455 HO, with specific "LS-2" intake and cast-iron exhaust header manifolds. Head mods: Port, cook, magnaflux, glass bead, convert to screw-in studs For the truly obsessed, 16 Grand Prixs were built with Pontiac's 421 Super Duty engines, rated at a staggering 370 bhp. Located at the back of the engine near the Distributor. Forged steel 6.625in (168.3mm) rods (Ram Air V style), Large-valve heads (valve diameter): 2.4in (61mm) intake, 2in (51mm) exhaust, Small-valve high-RPM head (valve diameter) 2.19in (56mm) intake, 2in (51mm) exhaust. Coil: GM The valve angle was reduced from 17 degrees to 14 degrees for better breathing. (imp.) One of the key modifications over the standard 301 4-barrel was the 301 Turbo block. It included a new camshaft with duration increased from 288/302 (No. The most valuable Pontiac GTO is the 1969 Judge convertible with the 370-hp Ram Air IV engine. However, a few dealers would offer them in the GTO or Firebird and do their own installations, such as Royal Pontiac who offered the "Bobcat" conversion. Not where most enthusiasts go first. Today, they have an average value of $430,000 in #3 (Good) condition, while the best in the world is worth about $550,000. 068) to 301/313 (No. Standard in the Firebird Trans Am, it was still a rare engine. These same heads were also used on the 1964 GTO 389 tri-power engines. (imp.) / 8.3 mpg (U.S.) / 3.6 km/l, more data: 1966 Pontiac Catalina 2 . Optional power was the 421/356 with Tri-Power or the 421 HO putting out 376 horses with Tri-Power. The company says engines running this cam benefit from headers, cylinder-head port work, a large-cfm carb, and an ignition upgrade. Preparation: Magnaflux, check for equal stroke and index, grind, polish 0.010-in For 1967 only Pontiac called this engine the Quadra-Power 428. of torque at 3,800 RPM in the GTO, and 340 HORSEPOWER at 5,300 RPM and 430-lb.ft. The 301 Turbo was unique since it had a beefier block than the 197779 versions (which carried on in the non-turbo versions in 1980 and 1981), a very mild camshaft with 0.35in (8.9mm) lift and 250 degrees gross duration, a 60psi (4.1bar) oil pump to ensure adequate oil to the oil-cooled Garrett TBO-305 Turbocharger, a rolled fillet crankshaft, a fully baffled oil pan, and a specific 800cuft/min (23m3/min) Quadrajet carburetor. gasoline (petrol) engine with displacement: 6902 cm3 / 421.2 cui, advertised power: 252 kW / 338 hp / 343 PS ( SAE gross . The compression ratio will be 10.6:1. Seat pressure: 110 pounds at 1.600-in The external dimensions of all their V8s, from 326455cuin (5.37.5L) were the same. All 196869 #9792506 Ram Air 400 blocks have 4-bolt caps. Tri Power engine however was optional. These are general guidelines. 544127 with larger 2.02/1.76-inch (51/45mm) valves entered production. In 1969, Pontiac also used a revised crankshaft out of a Pearlitic malleable-iron, although it still used the "N" casting letter. Even more powerful were the 421 Super Duty V8s that could produce up to 410 horsepower. Splayed main caps, head bolts tie into main caps. Pontiac went to open-chambered heads in some 1967 models and all 68 and up to improve power, engine breathing and reduce emissions. The engine build will be discussed in two parts. Ultimately Pontiac produced only 295 1973 SD-455 Firebirds (252 Trans Am, 43 Formula). Installed position: 110-deg As Stock drag racing heated up at the dawn of the Sixties, the factories were serving up a constant stream of engines, transmissions and lightweight body par. For 1974 another 1,001 (943 Trans Am, 58 Formula) were built, after which the SD-455 was discontinued. There was also the addition of dual exhaust, and for vehicles equipped with a manual transmission, a slightly more aggressive camshaft. Both Chevy and Ford had 427 cu in performance engines, so Pontiac simply referred to its 427 as a 428 to one-up them. A mere five were built, all with a four-speed transmission. Specs datasheet with technical data and performance data plus an analysis of the direct market competition of Pontiac Catalina Vista 421HO Trophy V-8 Tri-Power 4-speed in 1964 the model with 4-door hardtop sedan body and V-8 6902 cm3 / 421.2 cui, 276 kW / 375 PS / 370 hp (max) offered since October 1963 for North America U.S. special version. . Low-performance and two-barrel applications, the standard engine in full-sized Pontiacs, got 1.96in (49.8mm) intake and 1.66in (42.2mm) exhaust valves and pressed in rocker arm studs. Only 630 Bonnevilles were produced for 1957, all of them fuel-injected. Known as GM's performance-oriented division, Pontiac lived up to the hype by creating the first Muscle Car and kicking off the Muscle Car era. moniker from the shaker due to the disappointing public approval as the motor was not deemed to be "High Output". An evolution of the RA IV and H.O. After the 1974 SD455 was dropped the 1975 Firebird's top performance engine was an 'L78' Pontiac 400cuin (6.6L). SPECIFICATIONS. By 1949 work on a 287cuin (4.7L) OHV V8 had begun, but moved along slowly. Block/Crank combo: '64 four-bolt 421 / '64 OE 4.00-in stroke "Armasteel" was a trademark of pearlitic malleable iron developed by GM's Saginaw Metal Casting Operations around 1936, which was referred to as "locking ball" cast-iron, as opposed to the "flaking" type found in other engines. A big chunk of the appeal of the 1965 and '66 2+2 was the fact that you got a standard 421 under the hood: The 338hp, four-barrel 421-cu.in. Late in the model year the Ram Air 455 HO was made an available option for those GTOs with the optional "The Judge" package. Fuel pump: Will use 110-gph Carter It was rated at 376bhp in 1967 and 390bhp in 1968 and 1969. This new material had stronger alloys in the iron. The short deck engine weighed about 40lb (18kg) less than the other variants and had an 8000 rpm redline. The goal of making a Pontiac Hemi succeeded but the engine was never produced. It was renamed 428 HO for 1968. The 421 also marked the end of the option for a forged-steel crankshaft. There were a few 1962 Grand Prix models that came with a 421 SD from the factory so if someone is lucky enough to have one today then they have a car that is probably worth some decent money simply because of the rarity of these models.if(typeof ez_ad_units != 'undefined'){ez_ad_units.push([[580,400],'enginefacts_com-medrectangle-3','ezslot_2',115,'0','0'])};__ez_fad_position('div-gpt-ad-enginefacts_com-medrectangle-3-0'); Engine Facts 2023. The 1981 301 Turbo gained the electronic controls with an O2 sensor, feedback ECM and E4ME Quadrajet providing a slight reduction in output to 205hp (153kW) and 340lbft (461Nm).The 301 Turbo was limited to Trans Am and Formula Firebird production only. An innovative design feature was mounting the rocker arms on ball pivots on studs set into the cylinder head, rather than using a separate rocker shaft. This is it! 1966 Pontiac GTO. Pontiac ignited the classic muscle car era with a stroke of marketing genius. The first of the "big journal" Pontiac V8s, it had a bore and stroke of 4+332in 4in (104.0mm 101.6mm) and came with dual four-barrel carburetors. True Pontiac engines were designed and built in Detroitnot on a computer, but often by GI-bill-educated engineers who grew up working with their hands and now had a slide rule in their pocket instead of a greasy rag. Muscle Cars. The 421 SD Tri . 1963 - 389 SD Code 543797. The valve size increased as well, to 2.11in (53.6mm) intake and 1.77in (45.0mm) exhaust valves on high-performance heads. Simply put, what good is the power if the engine does not last? The premier SD 421 cylinder head was the late 1962-early 1963 casting #9771980 aka "980", featuring a larger 11.3cuin (185cc) intake port volume, flowing 230cuft/min (6.5m3/min) @ 28in (710mm). Wires: NAPA Belden 7 mm Also bowing in 1967 was the new Firebird, which had the . Type Size Carb Horse Power Tourqe; Tri-Power: 389ci: 3x2bbl: 360 hp @ 5200 rpm: 424 lb-ft @ 3600 rpm: Base 8 . Lift: 0.515/0.525 with 1.6:1 rockers Along with proper parts selection, accurate machining and assembly are also important. street engine. In 1967, Pontiac moved on to a technologically simpler nodular cast iron (invented in late 1940s) crankshaft, which they used until 1975. Instead, they were substituted with the L80 Oldsmobile 403, or the L37 Pontiac 301 if they still requested a 4-speed transmission. So large are the intake ports that the pushrods run through the center of each port via pressed-in tubes, in addition to streamlined airfoils over the tubes themselves to improve port shape, and increase flow velocity. In 1968, there was also a 350 "HO" which had increased power with the addition of higher compression #18 heads (#17 and #46 were the most common 2-barrel heads), a four-barrel carburettor and matching intake that was also used on the 400 and 428 engines. The manuals had Hurst shifters. It was called the Ram Air IV due to the planned use of four air inlets. The XS-code 389 was still rated at 360bhp at 5,200 rpm, same as the more common WS-coded Tri-Power 389, but performance was noticeably improved on acceleration runs. - P.Top - Correct Exterior/Interior. The 301 Turbo package mandated air conditioning, the THM350 (sometimes referred to as the CBC350 in various literature) non-lockup automatic transmission (THM350C lockup in 1981 Trans Ams), and 3.08 rear axle gearing. SELLER Glendale, Arizona 85305. Mechanical advance: 36-deg at 3,200 rpm The horsepower ratings of this era were often dubious, with engines rated higher or lower in output for advertising, political, or insurance purposes. However, the RA II was limited to a 1.50:1 rocker ratio, while the RA IV used a 1.65:1 ratio, which yielded significantly greater total lift and, therefore, superior flow and power. All 1977-1978 Trans Ams ordered with the 4-speed Borg Warner Super T-10 manual transmission received the W72 T/A 6.6 engine. Apparently at least one of these engines survives under the hood of an engineer's personal Pontiac.