I have an 84 z28 camaro. 5.0 H.O rochester quadrajet
i replaced the carb with a refurb quadrajet.
the carb came from an olds 307. 5.0. buddy didnt need it after he found out his block was cracked.
no problems with interchangability.

car runs like a bat out of hell untll about 4500 then it stalls.. no backfire.
i replaced cap/rotor, plugs/wires/pump/filter.
vacuum is all hooked up right.
i installed a fuel regulator.
its not too much fuel.... when i back off the fuel pressure it stalls at lower rpms.
ive ruled out all possibilities that it could be and im certain my fuel system cant keep up with my motor/carb.

what are my options?
can i tune the carb to not deliver so much fuel? or is it better to get a high volume fuel pump? a 305 oem fuel pump should deliver enough fuel for my set up its not radical....not to the point to where i need a high volume pump?!?!?!?!?.........

ive never tuned a carb before so i dont know what to adjust to lean it out....
but im thinking that i need to back of the fuel jets......

i hope someone knows what thier doing because i dont!!!!!

 

What secondary rods and hanger does the 307 carb have?

Have you verified that the rods lift when the AV opens?

 

If its your stock cam there is going to be no power past 4500 if its not bad valve springs kill high rpm power too

 

Its not like the thing is loosing power............. it is straight up falling on its face and bogging enough to where it throws me forward.....then it catches up and wants to shift........the secondaries are opening im sure of it.......im up a creek here i dont know what to do about it........im trying to sell this thing and no one is going to want to buy it if they cant punch it ya know?

its almost as if its starving itself........... would fatter fuel line make a difference rather than getting a high vol fuel pump?

 

Well this is going to be a Loooooooong story. So here it is.
I am a owner of a 84 Z28 H.O. I purchased it brand new in 1984. Still have it to! Anyway, the H.O.'s have a factory defect (recalled) for a bad fuel system.
Mine would run out of gas going up hill with a full tank of gas or accelerating up to freeway speeds, trying to pass someone etc. I took it back under warranty and the dealer couldn't find anything wrong. I told them to test drive it and stand on it. They wouldn't do it because of insurance reasons blah blah. They would only drive it around town at city speeds or rev the engine parked in a stall. It would only have the problem when the car was driven under load.
After getting a factory rep involved, it turns out the fuel system in the H.O. is not good enough to supply fuel under severe acceleration or going up steep grades.
GM made a retrofit kit to upgrade the system that required the removal of the fuel tank. I watched them do the change at the dealer under warranty. It envolved changing to a different gas tank with a intank fuel pump to help the factory manual pump. That fixed the problem!

Hope this helps

 

if it's a mechanical pump go ahead and buy a higher output aftermarket one sounds like fuel starvation issues.

 

rwb thats gotta be it.....that makes me feel a whole lot better now......instead of dumping money and pulling my hair out i know where to start know.....im thinking im gonna try getting a high volume fuel pump to see if that will nail it....if not, it looks likes i get to play with a gas tank.

 

You don't need a high volume fuel pump for a stock L69, they didn't have high volume fuel pumps stock, and didn't need it.
I'm still using a new stock LG4 replacement fuel pump for $25 on my souped up 350.

If your fuel pump is going bad, then replace it with a new stock one. I'd try that, if you are running out of pressure at higher RPM. That happened to me, I rigged up a vacuum gauge to a T off a new rubber line from fuel pump to carb, and saw 1psi at higher RPM. A new pump had me going in no time.

I'm assuming this is still an electronically controlled q-jet?

What secondary rods and hanger are on there? Have you played with secondary valve tension? Why are you using a regulator? You shouldn't need one with a mech pump.

 

regulator was to trouble shoot.......people here gave me the idea...guess you cant believe every one......the pump is new its stock....and as far as secondary valve tension no........i havent played with it....how do i adjust that...... im asuming that the tension could be too tight? causing them not to open enough..... i dont have vacuum hooked up to fuel pump i dont think theres a connection on mine.........but ill try tension on secondarys first........
how should i go about that