What is a Gran Sport/G.S./Stage 1?

By Darwin Falk, ROA #2077 & Ray Knott ROA #1

This article is re-printed from, "The Riview", published by the Riviera Owners Association


Many of the questions received by our Technical Advisors and here at our ROA office is what constitutes a Gran Sport/G.S./Stage 1? The questions usually revolve around how can I verify the authenticity of the option and what is included in the package? We publish this article with some hesitancy, as we don't want to make it easier for the unscrupulous to create G.S. clones. It is our hope that this article will assist those who are looking to purchase one and to give you the tools to make an educated decision. In the March/April 1991 issue of the Riview we published an article on how to verify a 65 Gran Sport.. This new feature article will cover all of the years when a Gran Sport, G.S. or Stage 1 was offered. We would also encourage you to contact the ROA office or the Technical Advisor, who covers that year for additional advise before shelling out large sums of money for a G.S.

Keep in mind that the Gran Sport was not a separate model, but an option, therefore the option was not reflected in the Vin#, except in 1972-1974. The G.S. option was first offered on the Riviera in 1965 and continued through 1975. A dual 4-barrel engine option was available in 1964 with an engine code of "KX" however; these 64 Rivieras were not identified as Gran Sports and did not have any GS emblems. Buick installed this engine option in only 2,122 Rivieras in 1964. The G.S. option was not always an engine option it varied from year to year. In some years it included a modified engine, while in other years it was only a handling package.

1965 Gran Sport
The subject of the 1965 Gran Sport has been extensively researched by several ROA members including Technical Advisor Leonard Scott, ROA 125, and the late John Hirsch ROA #47. The supportive data and references are too extensive to include in this article, but are in the ROA library if there are specific questions.

The Gran Sport option (A-9) listed for $306.38 and included the 360 hp Super Wildcat dual 4 bbl engine, modified exhaust and transmission, positive traction differential with a 3.42 rear axle, ornamentation and wheel covers. A separate Ride and Handling package (H-2) with 15-1 steering ratio and heavy-duty suspension was available for an additional $37.63. The Gran Sport option did not include the chrome wheels, upgrade interior, ribbed rocker panel or any other accessory. The engine was a 425 ci (code LX) with two AFB carburetors (front #3645, rear #3925) and distributor (#1111058) with a different throttle curve.. The engine package included a large fully chromed twin snorkel air cleaner, with a metal monogram that read "Super Wildcat," finned aluminum valve covers with "BUICK" in raised letters. The package also required a different upper AC bracket (#1367411) to fit over the taller valve covers. The exhaust pipes were increased from 2" to 2 ¼ "inside diameter and had less turns to reduce backpressure. The modified transmission had a "BS" code on its ID plate. The 3.42 positive transmission was standard but other ratios from 2.78 up to 4.45 could be special ordered.

'65 GS Front Fender Logo

The red letter and black background "Gran Sport" emblems were initially small 3" x1 ½." In mid December 1964 the emblems were changed to a larger 5 ¾" x1 5/16" size. The front emblems were mounted with studs onto the front fenders below the Riviera script. The rear emblem was mounted on the right side of the rear deck, below the Riviera script. When the larger emblem was used it was mounted on the left side of the rear deck. It should be noted that the 1965 was the only year in which Gran Sport was spelled out and the only one to use rear emblems.

The glove box emblem also included "Gran Sport" next to the typical Riviera script. The wheel covers that came with the package were the standard cap with a large spinner attached to the center. The medallion used in the center of all 65 wheel covers and chrome wheels was black with silver "R"

65 GS Dash

The Ride and Handling package was commonly used on the Gran Sport, but was a separate option. The modified steering improved the turning ratio from the standard 17 ½:1 (approximately 3 ¼ turns) to a 15:1 ratio ( approximately 2 ½ turns). The springs were stiffer and caused the car to sit an inch lower. The shocks were firmer, causing different weight distribution. Although it has been suspected that the front and rear stabilizer bars and bushings may have been stiffer, this cannot be confirmed. Since most cars have by now received new springs and shocks the handling is based on the replacement parts.

In 1965 Buick built 34,586 Rivierias, of these: 28,467 were equipped with the standard 401 ci engine (LT), 2,311 with the optional 425 ci (LW) and 3,808 with the Super Wildcat 425 dual 4 bbl (LX). There were 3,354 Gran Sports built in 65. The remaining 454 dual four engines were installed in standard Rivieras as an A-8 engine option. The A-8 option was also available on the, Wildcat and Electra 225. I do not have productions figures for the Wildcat or Electra 225 with the A-8 option.

 


Notice: BUICK and RIVIERA are trademarks of GENERAL MOTORS CORPORATION used with permission. The Riviera Owners Association is independent and not affiliated with GENERAL MOTORS CORPORATION or its BUICK MOTORS DIVISION    —Copyright 2007 Riviera Owners Association—