Too much fuel for Holley 650 carb
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Too much fuel for Holley 650 carb
I have a 1990 NA vert that is swapped to a 650 Holley carb instead of fuel injection. When I press on the gas pedal too hard the engine will bog. This includes at high rpm. Any idea how to mess with the air/fuel mixture without me screwing something up?
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I just got this car the other day so I'm not positive as to whether this info is right but according to the dude I got it from everything is stock other then the Holley 650 double pumper carb, MSD's and a street porting.
#4
well, i know it's not your fault and you're clearly new to this, but that makes no sense.
streetporting is not simply bolting on a part, and neither is a proper carburetor conversion. i'm guessing by MSDs you mean amplifiers (the boxes)? none of that stuff is simple. assuming you understood everything the previous owner told you, he was either a bit dense or he was trying to deceive/take advantage you in some way. i guess that's all irrelevant now though. your first priority is to find out exactly what you have and then seek help from there forward.
finding out which fuel pump you have is key because any pump meant for EFI is going to flood the car. some people use them anyway and just us a pressure regulator to restrict flow down. personally, i don't believe in that, but people do it. the point is find out what you HAVE as of now. the simplest way to do this is trace the fuel lines back toward the tank. (by the way, i obviously don't know what you know or don't, so if you know all of this already, say so. it will save us both some time.)
for the ignition, i know some people used the stock CAS and i have read of at least one case where people have gone so far as to trick the stock ECU to run with a carburetor. the simple solution of course would be using a distributor. again, you need to know what you HAVE before anyone can help you. the simplest thing i can think of with this is count ignition wires - do you have 4 or 6?
it is my opinion that a 650 is still too much carburetor for a streetport, but it can be made to work. this may turn out to be a part of your problem. the Holley question i asked is still unanswered, but it will also be important. it would be better to find out if you have an off-the-shelf Holley or a RB-prepped one. at this time, i don't have any guidance as to how to go about doing that though. i don't know if they put any of their logo stampings on them, but it won't hurt to look. at any rate, inventorying your fuel system and ignition system are the priorities now. we can deal with the carb itself later.
streetporting is not simply bolting on a part, and neither is a proper carburetor conversion. i'm guessing by MSDs you mean amplifiers (the boxes)? none of that stuff is simple. assuming you understood everything the previous owner told you, he was either a bit dense or he was trying to deceive/take advantage you in some way. i guess that's all irrelevant now though. your first priority is to find out exactly what you have and then seek help from there forward.
finding out which fuel pump you have is key because any pump meant for EFI is going to flood the car. some people use them anyway and just us a pressure regulator to restrict flow down. personally, i don't believe in that, but people do it. the point is find out what you HAVE as of now. the simplest way to do this is trace the fuel lines back toward the tank. (by the way, i obviously don't know what you know or don't, so if you know all of this already, say so. it will save us both some time.)
for the ignition, i know some people used the stock CAS and i have read of at least one case where people have gone so far as to trick the stock ECU to run with a carburetor. the simple solution of course would be using a distributor. again, you need to know what you HAVE before anyone can help you. the simplest thing i can think of with this is count ignition wires - do you have 4 or 6?
it is my opinion that a 650 is still too much carburetor for a streetport, but it can be made to work. this may turn out to be a part of your problem. the Holley question i asked is still unanswered, but it will also be important. it would be better to find out if you have an off-the-shelf Holley or a RB-prepped one. at this time, i don't have any guidance as to how to go about doing that though. i don't know if they put any of their logo stampings on them, but it won't hurt to look. at any rate, inventorying your fuel system and ignition system are the priorities now. we can deal with the carb itself later.
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More info
I took a closer look and the only place there is a part number on the carb I would have to remove it to look at. I've got the MSD ignition boxes and MSD blaster 2 ignition coils. I do have a fuel pressure regulator. And there appears to be 6 wires?
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More info
My friend that has an rx7 believes it is my secondary coils due to the fact that in Nuetral it doesn't bog when the gas is applied but off the line it does
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Thanks, the stock fuel injection stuff came with the car would I be able to switch back to that without changing my ignition setup?
#9
check this out:
https://www.rx7club.com/1st-generati...m-carb-479469/
can it be done? of course, but it begs the question, why? it would be much simpler to just remove the distributor and return the CAS setup. the stock computer stays happy with no trickery.
https://www.rx7club.com/1st-generati...m-carb-479469/
can it be done? of course, but it begs the question, why? it would be much simpler to just remove the distributor and return the CAS setup. the stock computer stays happy with no trickery.
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Is there any way for me to post a picture?
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I think he means the AFM.
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Which major city in Florida are you near? If you do not have the skill to identify the fuel pump, then you are in way over your head and you need to take the car to a professional shop. Fortunately, Florida has some pretty good shops. You would be better off getting this fixed by a pro, and then try to tackle easier tasks on your own as you are learning more about cars. Trust me, with a car this old there will be plenty of simpler things to fix so you will get lots of practice, lol.
I think he means the AFM.
I think he means the AFM.
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There is an outstanding shop about a 3-hr drive from your location. See if you can get it running well on your own, but if it can drive on the freeway and you want it really well-tuned then I highly recommend Lowe Performance in Sarasota. Since it is so far away I would recommend calling them first.
Servicie | Repair of Rotary Engine Vehicle - Lowe Performance
Servicie | Repair of Rotary Engine Vehicle - Lowe Performance
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There is an outstanding shop about a 3-hr drive from your location. See if you can get it running well on your own, but if it can drive on the freeway and you want it really well-tuned then I highly recommend Lowe Performance in Sarasota. Since it is so far away I would recommend calling them first.
Servicie | Repair of Rotary Engine Vehicle - Lowe Performance
Servicie | Repair of Rotary Engine Vehicle - Lowe Performance
#25
Look thru the top of the carb (engine off of course) with the choke fully open (if applicable) see if the secondary butterfly's are opening. They either open by vacuum or are controlled mechanically either way disconnect the linkage that makes them open.
Its rare that a car would FLOOD out when secondary's open. By driving the car on two barrels that should eliminate any questions of electrical problems. More likely not enough fuel like a giant vacuum leak when secondary's open. Easy to try but remember
no rotors came equipped with a holly 4bbl stock so it could go either way.
Its rare that a car would FLOOD out when secondary's open. By driving the car on two barrels that should eliminate any questions of electrical problems. More likely not enough fuel like a giant vacuum leak when secondary's open. Easy to try but remember
no rotors came equipped with a holly 4bbl stock so it could go either way.