Despite the short runners used in the LT1 EFI intake, the late-model motor offered more low-speed torque than the '70 version. Some of this is due to the dramatic difference in cam timing, as the milder hydraulic roller in the LT1 no doubt improved low-speed (below 3,300 rpm) torque production. From 3,500 rpm to 6,000 rpm, the original LT-1 offered slightly more power. The peak hp numbers were nearly identical, with the original version pumping out 353 hp, and the later mill making an even 350 hp. In the torque department, the '70 LT-1 produced 392 lb-ft at 4,100 rpm, compared with 379 lb-ft at 3,800 rpm for the LT1. In the midrange, the high-compression LT-1 offered as much as 13 extra lb-ft, but the difference was just 2 hp at 6,000 rpm.
1970 GM 350 Small-Block Engine - Clash of the Small Block Titans
The 1970 LT1 Takes On The 1996 LT-1 In A 350-Cube Throwdown