1991 Pontiac Grand Prix: The Twin-Cam 3.4 GTP Arrives

This record's own dek states that the twin-cam 3.4 V6 GTP arrives for 1991 at 210 hp. This record's own overview states that MuscleCarClub, crediting the Standard Catalog of Pontiac, gives 1991 Grand Prix production as 114,718 across LE, SE, STE, GT and GTP without a split by trim or engine, and that the compiled engine tables list a 3.1-liter V6 at 140 hp and 185 lb-ft, a 2.3-liter I4 at 160 hp and 155 lb-ft, and the 3.4-liter V6 at 210 hp and 215 lb-ft, all SAE net as compiled with no rpm given. This record's own keyFacts section restates that the compiled tables list the GTP among the 1991 models with that same 210-hp, 215-lb-ft 3.4-liter V6.¹

This record's own production section carries a single total row of 114,718, with a note that the bodystyle column is printed by the source as LE/SE/STE/GT/GTP and that the Standard Catalog states it as Grand Prix series production in its own Note 5; a second note states that no published trim, engine or transmission split of 1991 production was reached, and that two forum-quoted GT coupe figures disagree with each other and are held to unpublished leads only. This record's own prices section is empty for the year.^1,2

This record's own unpublishedLeads section carries both of those disputed counts: a Pontiac Customer Assistance Center reply quoted by forum members giving 2,546 Grand Prix GT two-door coupes for 1991, split into 244 with the 3.4-liter V6 and manual and 964 with the 3.4-liter and automatic, held back as an unverifiable forum reproduction of a manufacturer e-mail; and a VIN-decoding service quoted on the same forum giving 3,789 GT coupes, 2,464 with the B4U package, 2,008 with the DOHC engine and 1,781 with the LH0 engine, plus a separate post citing 327 manual-transmission GT/B4U cars, held back as a third-party database of unknown method that disagrees with the manufacturer-reply figure.¹

This record's own engines section carries the three entries matching the overview, with the 3.4-liter V6, RPO code LQ1, specifically noted as dual overhead cam with 24 valves, standard in the GTP and, per Consumer Guide, available across the 1991 line as GM's first 24-valve V6. This record's own transmissions section lists a three-speed automatic EPA-listed with the 2.3-liter four, a four-speed automatic EPA-listed with the 3.1- and 3.4-liter V6, and a five-speed manual EPA-listed only with the 3.4-liter V6, which Consumer Guide describes as standard with the 3.4 while the other engines were automatic only.^1,3,4,5

This record's own paint, performance and identification sections remain empty for the year: the 1991 Pontiac Full Line Prestige catalog, read on the page that carries the Grand Prix equipment table, prints no paint names or codes, no prices and no series or body-style codes, so nothing was entered for those sections rather than filled from another year or model. This record's own unpublishedLeads section still holds the two disputed GT-coupe counts described above. The GTP's arrival is therefore documented in this record through its engine and, now, through the catalog's own statement of what the Level III car was offered with, not through any measured or built-car evidence.

Pontiac's own 1991 Full Line Prestige catalog, a marketing document that shows what was offered rather than what was built, lays the Grand Prix out in five columns: LE sedan, SE coupe, SE sedan, GT coupe and STE. The 2.3-liter Quad 4 is standard on the LE and SE, the 3.1-liter V6 is optional there and standard on GT and STE, and the 3.4-liter Twin Dual Cam is optional on the SE, GT and STE. Fabrics named are Metrix cloth and Pallex cloth. Option Groups 1SA through 1SE bundle power and convenience items, and the Value Option Packages R6A and R6B combine Custom trim with gauges, radios, sport bucket seats or a head-up display depending on the model.

The catalog's Vital Specs box gives a curb weight of 3,214 to 3,434 pounds, a 16.5-gallon tank, and a 15.2 cubic-foot coupe trunk against 15.5 for the sedan, with a 7.5-second 0-60 time quoted for a GT with the 3.4-liter, 5-speed and 3.67 axle. It prints the 3.4-liter at 210 hp and 215 lb-ft, with 200 hp footnoted for the 4-speed automatic, which this record's conflicts section sets against the compiled 210 hp figure. Tires step from P205/70R15 touring on Level I to P215/60R16 Eagle GT+4 on Level II and P245/50ZR16 Eagle Gatorback on the GTP, and the interior tables give coupe and sedan head, leg, shoulder and hip room in inches.¹