Engine Need help 90 mustang carbed 5.0

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Well I checked my float levels today and surprised to see the bowls were completely filled above the sight plugs made a wonderful mess of fuel but they are set equally to where I slightly rock the car and I see fuel come out wondering if this makes sense of my problem? Thanks for responses
 
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I bought the car about 2 months ago maybe longer anyway factory 2.3 5 spd 90 mustang hatchback swapped to a 5.0 from a 84 truck carbed true dual exhaust no cats brand new holley street warrior carb electric choke anyways the problem runs fine until randomly under load motor starts bogging then dies have to pump throttle to get it started has no problem starting after u pump throttle couple times I've set my idle mixtures screws with a vaccum gauge got my idle set around 800rpm im thinking accelertor pump needs adjusting or float bowls aren't filling up all the way please any help appreciated sorry am new here not sure if I should post here or not thanks tho
Check for sticking needles and seats in your Holley. Use non alky gas or install steel needles then recheck symptom. Used to just dry them out. Under warranty we used to take the sticking needles out of one GT mustang and replace them with new ford ones. Then next week when another mustang came in with the same problem we could lust use last weeks needles to fix this weeks mustang. We had so much trouble with the needles sticking, parts could not keep enough needles in stock. Finally figured it out that steel alky needles were the fix. Viton Smighton . I use steel ones in mine to this day. The alky needles also have a bigger window which lets more fuel in quicker. In case you are going racing like me. 6-502-2 is one Holley part number for the .120 seat ones. I do not remember them making three sizes, maybe look for the .097 ones
 
Well I might of figured it out today I went through and readjusted the whole carb floats choke idle idle mixture everything and I decided to screw my idle mixture screws all they way tell they barely touch and the one on the passenger side was like too turns farther out and the first time I set them I just trusted holley them saying its set close out of the box 2 turns off on one side isn't close sorry so reset everything and it idles way better and before u could hear a slight misfire every so often out the exhaust its gone now haven't drove it yet but running way better all together so will test drive it and let u guys know thanks again everybody still have to get a regulator just don't know which one I want to get
 
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Well I am back sorry took so long but problem is still occurring carb is all set right good fuel pressure installed a inline spacer and also a carb spacer and heat isolator gasket because I determined it is vapor locking well turns out its not in the carb its somewhere in the line from the tank to the mechanical pump up to the inline filter which then is like 3 or 4 inches from my carb because I just tested it today and it stalled pushed it across the street into a parking lot cause it wouldn't start this time low and behold inline filter empty got a tow a couple blocks to my buddies house and got there and let it sit for an hour starts right up after line builds fuel up again im not sure what to do do I run all new rubber line instead of steel or what I new it was gonna be a stupid reason but not how to fix it I was thinking coil but I wouldn't think that would cause no fuel in the filter and recommendations appreciated thanks guys
 
A soft fuel line is a dangerous line. Last time I had a carb car get a track safety inspection, there was a maximum length of hose used limit.
Check for places where the exhaust and fuel lines are close. I have used DEI heat shield to keep fuel line after the fuel pump to the carb cool. It should help before the pump if the exhaust and fuel line cannot be moved apart. I think they and other places make heat shield that is sewn to side over the line and other that golds over and is held together with Velcro.
 
Well I am back sorry took so long but problem is still occurring carb is all set right good fuel pressure installed a inline spacer and also a carb spacer and heat isolator gasket because I determined it is vapor locking well turns out its not in the carb its somewhere in the line from the tank to the mechanical pump up to the inline filter which then is like 3 or 4 inches from my carb because I just tested it today and it stalled pushed it across the street into a parking lot cause it wouldn't start this time low and behold inline filter empty got a tow a couple blocks to my buddies house and got there and let it sit for an hour starts right up after line builds fuel up again im not sure what to do do I run all new rubber line instead of steel or what I new it was gonna be a stupid reason but not how to fix it I was thinking coil but I wouldn't think that would cause no fuel in the filter and recommendations appreciated thanks guys
Did you type that all in one breath?
Your fuel pump may be getting hot and by passing, I would look into possible installing a in tank pump, they last longer.
 
I moved my fuel lines the best I could no help mostly steel line only about 6 inches going to the carb which is new line and short peices connecting the tank supply and return lines to the pump which are also new when I put the motor back in fuel pump is basically new did it right before I got the car thinking the pump went out but the 351w cam lobe was free spinning for the fuel pump but thats fixed now new sending unit and short peices of rubber hose there tank vent is working so my next thing i guess is slide some insulation over the lines and see if that works