Hey guys I'm new here. Got a small problem with my 75 f150. I bough it and it had an edlebrock carb. 4 barrel, 850 carb. It's either getting too much gas or too little. Whenever I hit the pedal it bogs down and almost dies. Also it runs good at idle but when I put it in gear it starts to bog down. Don't know much about carbs. So I there a way to adjust it or should I just down grade to a smaller carb? Thanks for the help.

 

Ummmmmm... We're not clairvoyant. What engine? And is it "built"? If so, clue us in on the specs... like cam, RPM range, usage, heads.

Regardless, it sounds over-carbed unless it is a 400+ cubic inch monster turning 8,000 rpm when ya drop the clutch or mash the skinny pedal.

 

Personally, I think "Over carbed," is a little general and can be fixed with some tuning. But maybe that's just me.

Youre probably running a little on fat side, as the mindset with carbs seems to be that more fuel is equal to more power; The Edelbrock carbs are set up from the factory for something like 9000000 CID engines.

You can download the Edelbrock manual for free that has some great reading in it about how carbs in general work and how you can adjust what you have, including floats and your carb. You'll probably need to buy the adjustment kit, which will come with needles, jets and springs. The manual will also tell you which accelerator pump jets are installed; If your model has anything larger than what the 1406 has, any setting will likely be too rich without changing out the nozzles...

It may seem like an un-needed expense, but a good air/fuel gauge will REALLY help you tune and understand how things are working.

Have you pulled plugs to look at them? Got some pictures to post up? Betcha they are black as can be, which will mean youre running pig-rich; The plugs can tell you a LOT about how things are running. Everything from timing to fuel ratios can be found out from them.

BUT...as stated above, without a little more information, like which springs, rods and what not is in your carb and what sort of engine youre running, it's mostly a shot in the dark.

 

Everything is stock on the engine except for carb. . It's a 351m. Thanks again.

 

While it may not be directly related to your problem, 850 CFM is way too high for this engine. I don't think it's a worthwhile exercise to troubleshoot this combination when you have such a grossly over-rated setup to begin with. It's like trying to figure out what medicine to take for a cold when you have the flu.

 

Yeah I know it's too high I was just wondering if there was any way to adjust it for the 351

 

There is; it's all explained in psychlopath's post. I'm just saying that sort of tuning exercise is something that one needs to do anyway on any setup, and I think it makes sense to go through that effort on the right carburetor in the first place. Regardless, pick yourself up a vacuum gauge.

 

Like everyone else said, 850 is way to much for that engine, especially if the only aftermarket addon is a 4bbl intake. If I were you, I'd sell off the carb and find yourself the appropriate size for the engine. I think the 2bbl stock was a 500, so get something between 5-600 cfm

-Jameson

 

Thanks everyone for the help. Really appreciated.