Hello all, hoping someone can help us out here.

My boyfriend and I have been working on a swap on our 96 blazer. Decided to go carb mainly because he wanted to avoid the headache of the wiring harness. Have Edelbrock 650 cfm installed...rebuilt. Also used the 700R4 tranny.

Got most of the bugs worked out and took her for her first spin and the thing kept stalling out. We did several things to tweak the fuel system, been through 5 fuel pumps...3 electric, 2 mechanical...one of each was brand spanking new, the others were rebuilds. New filters, new lines, vented cap, filter between carb and pump not pump and tank, etc.

Fuel pressure has been reading steady at about 5.5, which for this carb is supposed to be on target (according to Edelbrock manual). Now we are at a loss. I have been researching like crazy and the only thing I've been able to find is that the mechanical pump we are now using does not have enough gph to push the fuel. Boyfriend is a newly graduated but skilled mechanic and has tried everything he can think of. We could really use some ideas.

 

Additional Details:
Swapped original 4.3 tbi for 88 sbc 350 from chevy short wide. As mentioned above, Edelbrock 650 cfm carb and 700R4 rebuilt transmission.

ELECTRIC PUMP
Electric pumps ran on toggle switch with regulator and return.
Initial problem: Stalled on acceleration. Had hard idle but kept running. Switched pumps (total of 3) Wasn't getting fuel to carb...bowl was dry.
MECHANICAL PUMP (currently installed)
Airtex mechanical pump.
Similar problem though rather than only on acceleration, stalls at various times. Every time it stalls it seems the next stall comes sooner. Pump was primed and ran great for about 20 or so miles before first stall. After sitting about an hour went home and next stall was half the distance, then half the distance again. etc, etc.

 

Hmm. bump the pressure up to about 6.5 and see if it helps with it. What kind of regulator are you using? they have been known to be a hit or miss. Pull the feed lines off the carb and look for an restrictions.