i just hooked one up today, and i seem to only get 5", and it bounces from 4-5.... at 800rpm...
my cam is a isky 278/240@050 108LSA - performer rpm with a holley 4150 chokeless carb

14* initial, around 42 or something total...
anyone have this problem? the timing tab shows 8 degrees advance, while my electronic dial-back timing gun shows 14 degrees, with the mark lined up at 0* TDC

i was trying to tune my idle so it is leaner, but i cant seem to get over 5-6" without raising the idle to 1000rpm

i think i have a vacuum leak??

the engine runs great and pull great power, but if i rev it, it drops to 1300rpm, then slowly back to 800rpm...

also, where exactly do i add weld on the weights to limit my mechanical advance? im a little confused...

Is 278/240 @ .050 right? 240 sounds kind of strange.

278 advertised, and 240@050...

Since its an Isky, I'm guessing its a solid? I heard solids do that when the valves aren't properly adjusted.

yes - it is a solid. i think i will redo my lashes then, guess it would be a good time to retorque the steel shim headgaskets too

Is that the Z-25 cam ? If so that cam should pull 12 in at an idle fairly easily.Something is not quite right.

Same specs as my Clay Smith & it pulls 11" in a 385 idling @ 750.

its Z-45

i will check the vacuum and lashes today