L78 horsepower

[bergy]

Yikes! Thanks for all of the input. We were able to coax a few more HP after re-jetting. Then we put the shop carb on and it woke up! 446 hp at 5700.

[VintageMusclecar]

Originally Posted by bergy

Yikes! Thanks for all of the input. We were able to coax a few more HP after re-jetting. Then we put the shop carb on and it woke up! 446 hp at 5700.

Sounds about right.

I installed a 3910 on my 496 for the initial dyno tests and the engine picked up somewhere around 20 when I swapped to a 3418 (`67 L88 855 vacuum secondary). During the last series of tests, the engine picked up another 30+ when I replaced the L88 carb with a 4781 850 double pumper, and another 20 when I switched to a 1000 HP (I built & calibrated myself). That's over 60 HP just in the carbs.

The factory carbs are good, but they do leave room for improvement. Comparing them to a newer "race" type carb really is an apples to oranges comparison.

[1968 nova ss]

recently I dynoed my 396/375 hp motor for my 68 nova ss matador red car...with lots of tuning through stock manifolds and 520 lift flat tappet camshaft best hp was 465 hp and 455 torque.. Chris teed

[WILMASBOYL78]

Chris...those are very strong numbers with cast iron manifolds....nice job.

-wilma

[1968 nova ss]

tom, we built the motor to run purestock drags in Stanton, Michigan yearly race..but, didn't quite make it..alot of little things make a difference..it runs good behind the Muncie and 4 ;10 gear..