Grand Sport Twin Plug Heads

[Invetterate]

A long shot, but does anybody have any information on the specification, manufacture, photos or anything else to do with the twin plug heads [and ignition system] that were originally an option for the 1963 racing Grand Sports?

I can't seem to really find anything much on the net [although I might have missed something], so any help appreciated.

They were apparently designed and built to increase the output of the already formidable all-alloy 377ci Duntov race engine. It was decided not to risk the extra complexity for the Nassau Speed Week, but I believe they increased the power from c485hp to c550hp. Given the Grand Sports weighed in at just under a ton, you can imagine how even more potent these heads would have made the car and all in 1963!

Thanks.

Mark

 

[Steven Smith]

I have had a good search using several different browsers and can only find the below:
Corvette Grand Sport Twin Plugs
The Grand Sport Corvette, a limited-production model, was introduced in 1963 as a racing variant. The twin plug heads, an optional feature, were part of the car’s high-performance package. Although not widely documented, it’s believed that only a few Grand Sport Corvettes were equipped with twin plug heads, making them rare and highly sought after by collectors.

Specifications and Manufacture
The twin plug heads were designed to increase power output, reportedly boosting horsepower from around 485 to 550. This upgrade was likely intended for the Grand Sport’s racing endeavors, particularly the Nassau Speed Week. However, it’s unclear whether this modification was ever implemented on a production car or solely used for racing purposes.

Photographic Evidence
Unfortunately, there are no known photographs of a production Grand Sport Corvette with twin plug heads. The rarity of this configuration and the limited documentation make it challenging to find visual evidence.

Legacy and Collectibility
Today, the Grand Sport Corvette, including any potential twin plug head variants, is highly prized by collectors. The rarity and historical significance of these engines make them extremely valuable, with prices ranging from hundreds of thousands to millions of dollars depending on the car’s condition and provenance.

In Summary
The Grand Sport Corvette twin plug heads are a rare and elusive topic, with limited documentation and no known photographic evidence. However, it’s believed that a few Grand Sport Corvettes were equipped with this high-performance feature, making them highly sought after by collectors and enthusiasts.

 

[Invetterate]

I have had a good search using several different browsers and can only find the below:
Corvette Grand Sport Twin Plugs
The Grand Sport Corvette, a limited-production model, was introduced in 1963 as a racing variant. The twin plug heads, an optional feature, were part of the car’s high-performance package. Although not widely documented, it’s believed that only a few Grand Sport Corvettes were equipped with twin plug heads, making them rare and highly sought after by collectors.

Specifications and Manufacture
The twin plug heads were designed to increase power output, reportedly boosting horsepower from around 485 to 550. This upgrade was likely intended for the Grand Sport’s racing endeavors, particularly the Nassau Speed Week. However, it’s unclear whether this modification was ever implemented on a production car or solely used for racing purposes.

Photographic Evidence
Unfortunately, there are no known photographs of a production Grand Sport Corvette with twin plug heads. The rarity of this configuration and the limited documentation make it challenging to find visual evidence.

Legacy and Collectibility
Today, the Grand Sport Corvette, including any potential twin plug head variants, is highly prized by collectors. The rarity and historical significance of these engines make them extremely valuable, with prices ranging from hundreds of thousands to millions of dollars depending on the car’s condition and provenance.

In Summary
The Grand Sport Corvette twin plug heads are a rare and elusive topic, with limited documentation and no known photographic evidence. However, it’s believed that a few Grand Sport Corvettes were equipped with this high-performance feature, making them highly sought after by collectors and enthusiasts.

Thanks, Steve - appreciate your time on this.

Unfortunately, this accords with my own findings! Bother!

I have one other lead courtesy of Chris Sale - I'll keep you updated!

Cheers,

Mark

 

[Roscobbc]

Its interesting that in the 'high octane' multi million dollar world of rare of 'desireable' muscle, performance and race Corvettes there are still unknown to most people, and even knowledgeable enthusiasts rarer options and prototypes to be discovered.........