Long Lead LT2 454 Corvette
Long Lead LT2 Corvette
This LT2 454 Corvette gave us a glimpse of a special high performance Corvette option for 1970 that was cancelled at the last minute.
Production of the 1970 Corvette began with an enlarged version of the 427 big block Chevrolet engine. Thanks to a longer throw crankshaft, Chevrolet’s largest engine for 1970 was four hundred and fifty four cubic inches. The successor to the 427 L-88 engine was to be called the 454 LS-7, and the replacement for the all-aluminum 427 ZL-1 engine was to be called the 454 LT-2 for this newest model year.
The Chevrolet engineers routinely hosted a “Press Preview Day” for the automobile journalists to view, photograph, and test the latest cars from the upcoming new model year. For many of the journalists in attendance, the 1970 Press Preview Day was one of the most memorable test days of their lives. This was all credited to a very special Monaco Orange 454 Corvette nicknamed the “Saturday Night Special” by the GM engineers who built it.
Although this particular orange Corvette may have been in 1969 exterior trim, but under the hood was all 1970, and it packed the biggest “punch” that these journalists would experience in their careers. This Monaco Orange Corvette was powered by the all-aluminum 454 LT-2 engine, which was mated to a heavy duty turbo hydramatic automatic transmission that transferred power to its independent rear end with low 4-series gears.
Simply placing the Corvette in “Drive” and punching the gas pedal resulted in low 11 second ¼ mile elapsed times. These time slips were the quickest runs that most, if not all of the journalists experienced in their lifetimes. Only a handful of drivers had the pleasure of running this LT-2 Corvette in the 10 second range. With the help of “neutral to drive drops” the LT-2 Corvette would run the ¼ mile in 10.6 seconds at 132 MPH.
This LT-2 Corvette shown here is owned by Dave Miller and is affectionately called the “Long Lead Corvette.” It’s as close to an exact replica of the original “Saturday Night Special” as possible. Its detailed recreation can only be credited to the original group of powertrain engineers that originally created the SNS. Gib Hufstader, Tom Langdon, Dan Crawford, Dave McLellan, Bill Howell, and Denny Davis built this Corvette with the assistance of Dave Miller, Kevin Lambert (who acquired the LT-2 aluminum engine block), Werner Meier, and his Master Works Restoration facility.
The performance of the Long Lead Corvette is basically identical to the Saturday Night Special as it was tested at 10.8 seconds in the ¼ mile using today’s fuel and a slight difference in the rear end ratio as compared to what was available in the summer of 1969.
A view of the all aluminum 454 LT-2 engine with an L-88 type air filter lid which required modifications at the front and rear of its assembly to clear the extra large Holley Dominator carb. Denny Hummel of CHESS Racing built the LT-2. Denny’s friend, Wally Booth selected the camshaft profile which was ground by Crower. Tom Langdon, who tuned the original LT-2 while at GM, designed the intake to match the original modifications required to accept a Holley Dominator. Note the missing wiper door vacuum actuator was removed in the quest of further weight reduction of the Long Lead Corvette.
This Monaco Orange Corvette exemplifies a top of the line performance optioned 1970 Corvette. It’s so unfortunate that this engine option was cancelled.
Two other 454 engine options were cancelled for the 1970 model year. The LS-7 454 which was scheduled to replace the 427 L-88 engine option was cancelled just as factory production of the 1970 Corvettes started in St. Louis, Missouri. The LS-7 would be available as a crate engine from Chevrolet for enthusiasts who couldn’t live without one. The tri-power L-71 427 engine was to be replaced by the LJ-2 tri-power 454. The LJ-2 was in reality an LS-6 454 with the tri-power setup, but unfortunately, multi-carb engines were eliminated from the General Motors line-up for the 1970 model year. The Corvette engineers made a request in the summer of 1969 for the LS-6 454 with the single Holley carb as a 1970 option, but unfortunately, it was also not approved.
Originally built from a 1968 Corvette for the press preview day for the 1969 models, the Saturday Night Special was later modified again for the 1970 press preview day which was held at the Milford Proving Ground. This Long Lead Corvette has been beautifully recreated in the same manner by the same group of Corvette engineers.
I would like to acknowledge that this Long Lead Corvette project would not have been possible without the assistance of the Petersen Archives and its archivist, Thomas Voehringer, who located photos from the original photo shoot titled “1969 Long Lead.” From these unpublished photos, Dave Miller, Werner Meier and “The Team” were able to recapture the details of the original Saturday Night Special, which helped create this beautiful replica. The memories of the original press journalists such as Eric Dahlquist, Joe Green and Joe Oldham helped the team replicate items such as the gear lever block off plate to bring the Long Lead Corvette to an even higher level of authenticity. This project would not have been possible without them.