Carb Stumble Flathead with 94's

I need a little help. My engine stumbles when you crack/ burp the throttle. Heres what i know: 51 Merc, Fenton Intake two Holley 94's with 71 squrters, 48 jets, 4.5 power valves, acelerator pump in position #3, cam is unknown, timing set at 21 degrees, Mallory dual point. It appeares the front squiter dumps plenty of fuel the rear carb doenst seem to dump fuel. I have balanced the carbs with a uni sinc. Pulls about 15-16 on vacume at the intake. My dad thinks it needs more squiter??? Do they make bigger squiters?

Any help would be appreciated. I am dying to drive this thing!!

 

is the rear carb getting gas, or need to be cleaned and rebilt?
pogo

 

Both carbs are rebuilt, i think i am going to pull the rear one off and check the squirter to make sure it is not clogged. i assumed it is getting fuel.

 

If rear carb is not squirting when it is supposed to, it is feedin mixture that is too lean, I would think. Fixxit and see what happens...check passage to squirter, holes in nozzles, and also the little check valve ball at the bottom of the pump well.

 

Bruce, i was hoping you would chime in!! I have noticed you feedback and other info/ help you have provided for others. thanks
here is an update: Found right side of squirter clogged, cleaned it but no avail. 2nd removed carb and poked tiny wire thru all holes and blew with air, this time i also removed the ball in the bottom of the accel pump well and installed a new ball out of a kit. installed another 4.5 power valve (new generation). installed carb and improved greatly, but not quite still up to snuff.
my next question is should i try a 3.5 power valve next???

 

Hello..I don't know what you can do to those 94s, they have a history of stumbling at hard acceleration..
Duane..

 

Another help tip i picked up somewhere that has really worked for me. We soak the squirter parts in " Snow-bowl" toliet cleaner. I usually buy from the dollar store. it has hydrocloric acid and does a great job removing the inside dirt sand etc.

 

Power valve likely doesn't influence things till somewhere beyond 1500...its fuel is delivered via the same path as that from mains and really should not feed anything until enough air is moving to work venturis.
Ball: Its seat might be bad--usual high tech cure is to put a ball on the seat, smite it with hammer and punch.
Your car is also running on the off idle circuit (holes tight above idle adjust holes) til higher flow happens. Be sure idle jets are clear and check the bleeds in idle passages at fronts of nozzle bars. These are super tiny holes within larger holes and oft remain clogged even after soaking. If you have to probe, be very careful not to gouge the holes...perhaps use small copper wire unraveled from electical wire or a deburred butt end of a tiny drill bit.