i changed out my motor a few months back all specs in sig...
it feels like its got some decent power but its being held back. its fine under part throttle but wot it shakes and feels like the engine is loading up from 3-4k as soon as it hits 4k it revs smooth again. any ideas on what to check?

 

bump...
no one knows what i should check?
i was thinking maybe a carb problem vaccuum secondarys not opening till 4k maybe?

 

i would bet carb... the shuddering seems like you might be lean. what is your timing like?

 

really not sure.... i used all my old 305 stuff and the pointer on the 305 timing cover is in the wrong spot for the 350 balancer i used. the 305 pointer is at 12 o'clock and tdc on the 350 balancer is somewhere around 2-3 o'clock. i set timing by ear and sotp driving. i did verify its not the timing though... i changed it multiple times hooked the vacuum advance up to full and ported sources no matter what i did with timing i had the same problem from 3-4k. my brother in law was using a holly dp on his blazer until he could get his qjet rebuilt... he just got that done so i think im gonna ask him if i can borrow his carb to check it.

 

the engine the balancer came off of has very little to do with timing tab location... the 6in balancer has the timing tab in one location and the 8in is in the other... either balancer will be fine on either 305/350...

it sounds like you have a lean spot when the secondaries are starting to open... but edelbrock... i have no idea how to correct that never understood all of the rods and hangers what nots

 

my 305 balancer had a long sleeve on it with the timing mark. does that come off? maybe im looking at a groove that sleeve fits on or something?