I've replaced the inline fuel filter. No significant help/change, but at least that's one check off the list. Fuel pump seems fine, I think I am getting good flow from it, no objective measures yet, but a buddy of mine says he has something we can use to test the pump so I will try that when possible.

I've looked into the carb, and it seems okay, but since I have little to no experience, I am not sure if I am getting a decent shot of fuel. How do I tell? What do I look for?

I have read up on Holley's website about checking the float level and being able to adjust it, it seems straight forward enough that I should be able to do it. Unfortunately, it also looks like I need the car to be idling to do this and right now I can't get her to idle. I need to continuously pump the accelerator to keep her from stalling out/get bogged down.

The other thing I have noticed is that the choke on the carb is always close to all the way open. When a neighbor briefly held it closed the other day, the engine started to act a little better. He didn't have time to stick around a confirm this, so I will try to do this tomorrow with my roommate. I have a Holley 650 cfm model number 4150 (part number R80783-1) with an electronic choke. I have noticed for as long as I have had this car, she never acted like she had an electronic choke (this could just be a misconception on my part though). From a cold start the RPMs would drop to 1000 or less and she would try to stall out unless I acted as the choke (i.e. kept her RPMs up for a little while - maybe this is part of my misconception - please see question at the end of this post). Once she was warm there were no problems (until recently). I assume (maybe incorrectly) that with the electronic choke, she would idle faster until she is warm.

I mention this because since I have been playing with her trying to figure out this issue, I have noticed there is a red lever (fast idle cam assembly - per holley's exploded view diagram) coming off the electronic choke that prevents the choke rod from allowing the choke plate to fully close. So I am wondering if the electronic choke is broken, maybe keeping the choke open more than it should be. I can pull on the accelerator and push on the choke plate at the same time (car is off) and "reset" this red lever somehow and then close the choke plate myself, but the red lever never remains in the up position thus allowing the choke to close by itself without assistance.

Basic question: if the engine is cold should the choke be more open or more closed? Then I assume as the engine warms up the choke will then be more of the opposite to what it is when it is cold?

Another basic question: Will the electronic choke on my carb affect the idle rpms or just affect the air/fuel mixture or a combination there of?

Also, a big thanks to everyone and all of the responses I have received so far.

 

With a cold engine, the choke butterfly should be closed. You should have keyed power to the choke, which will make the butterfly open up as it heats up the wind-up coil element. Check the choke electrical connection with a meter or test light.
Yes, the choke affects the idle, as the choke operates a fast idle cam on the passenger side of the carb. As the choke opens, the fast idle cam steps down until your arm on the drivers side is resting on the curb idle screw.
Read this, everything you need to know about adjusting your carb is there: http://www.holley.com/data/Products/...9934-3rev2.pdf

 

This is much better info than earlier! The choke is supposed to close when the engine is cold, and it will also raise the idle when completely closed until the engine warms up.
With 12 v. power to the choke you can turn the key on, and step down on the gas pedal once and it will allow the choke to "set". Then when you start it the idle will be up, and the choke closed, and it should not only idle, but drive better when cold.
Once you determine it has power with a test light, then turn the key on, and set the choke, then get out and look to see if it's closed. If it's not the choke is either out of adjustment, or defective.

 

Okay so it's been a while since I have had a chance to post anything about all of this. Hopefully I won't make this too long... here we go...

when we last left off I was trying to diagnosis what was causing my hesitation/idling issues. I worked with the electronic choke (which I found was not installed properly, I wonder if someone simply let the spring disconnect from the choke level so that the choke was always open because they were having problems with it). I played with that some, and got the car to start and run, but just barely. So I started looking for other problems.

I knew the car was running rich, but wow...take a look at these spark plugs...




WOW!

Here is a side by side after a buddy of mine helped me clean them up and regap them...



after cleaning them all up, I put them back and let her rip. It helped some, but didn't take care of all of the issues. So I decided to delve into the carburetor.

 

After getting the carb off the car and taking it apart I found this...



So since this is among other things a big learning opportunity for me, I decided to clean the carb up and do a rebuild...replace all the gaskets, clean everything up, new needles/seats, etc.

Here's some parts all shiny and clean...even pretty new gaskets...





Yay! I am all excited, looking forward to getting it back on the car and tuning it all up.

In retrospec, a major part of the problem may just have been that everything was just way out of tune. But hey it's been a good learning experience.

Unfortunately, part of the learning experience along the way was...DON'T OVER TIGHTEN...whoops. Putting everything back together, I ended up striping one of the screws on the primary fuel bowl. I thought it was going to be okay...it seemed like the screw was staying put and so I put the carb back on the car. I fire her up and then noticed fuel leaking around that screw...DAMN! So I try and find a slightly longer screw that I might be able to get to work. Turns out Holley used a 12-24 screw for the primary fuel bowl screws ... read very hard to find. Even the local mom and pop hardware store that has everything you would never expect to find (and can't find anywhere else) doesn't have the screw I need. they have the right size (which no one else did) but just not one long enough.

So at this point, it's clear I am over my head and need help. So I take it to a local shop who says they should be able to tap out a new probably slightly larger hole or find another way to help me out.

This brings us to yesterday...

 

So yesterday, I bring the carb to the shop. We taking it apart, but are having a lot of trouble getting the primary metering block off of the main body. We finally are able to pry it loose and well find parts of the casting of the main body stuck to the gasket on the primary metering block. Well ****...I say. Now what. My mechanic says he will hold on to the carb and talk to some of his buddies who he works with when he's working on carbs.

He calls me today and says they have seen this before, where the ethanol that's in modern day gasoline sometimes eats away at the carb.

So my question is now, do I have him get a new mainbody and then rebuild the carb or since between parts and labor this will probably cost at least half of what a new carb would cost...should I just get a new carb?

If I go the new carb route (which I am kinda of leaning towards), do you all have any recommendations?

My old carb was a Holley 650 cfm Avenger carb from Sept 2006. Model number - 80783-1

Some specs on my engine: a 350 4-bolt main (010) block with a .030 overbore (making a 355). I have Speed pro forged pistons 10.5-1 compression with chrome molly rings. Crane cams flat tapped 0.500 lift, intake and exhaust 248n duration. Bowtie cylinder heads shaved to a 58cc combustion chamber with oversized valves, and big block springs.

First a basic question (maybe) - was a 650 cfm carb to big for this engine or is the size fine with proper tuning?

Second - do you all recommend Holley carbs? should I get another one? or should I look at something else?

Third - or should I go with the rebuild of my current one?

Lastly - if you made it this far, I am impressed and thanks for reading.

 

When I saw the look of the metering block in the picture and the rusty color on the power valve, the first thing I thought was ethanol mix gas, and how it attacked your carb.
Considering the stripped main body, and now the metering block, I'd get a new carb myself. The one you have is an excellent choice for the engine combo, and I think I'd just get the same thing again.

 

thanks as always for the quick response, I should be getting used to it, but it's still a pleasant surprise.

Are there any carbs that are more resistant to the ethanol mix? What else can I do to avoid this problem in the future? Can you even get gasoline without ethanol in it? Is Holley the best choice for me or should I try another manufacturer? Obviously that last question is probably subject to personal opinion/experience.

 

Gas without methanol is still available, but hard to find, and expensive. There are some additives available to help with the ethanol problems, but the best thing is to drive the car more often to avoid the gas sitting and going bad. When the bowl levels go down the air causes more of the corrosion from ethanol. Same for the inside of your gas tank, so always store it full. If you're driving the gas sloshes around, and it doesn't get the ugly corrosion of a half full tank or carb that is sitting.
I'm a Holley fan, so that would be my choice. Maybe someone will chime in with a reccommendation and an Edelbrock they think would be good.

 

I like Holley's, but everybody has their favorite. If you buy a new Holley, it's E-10 (pump gas) compatible. The issue is with the rubber components, but you can get upgraded parts for your old Holley. I'd imagine other carb manufacturers are making theirs compatible with the "newer" pump gas as well, they'd have to or the company wouldn't survive.