2 Issues

[CJB3884]

I'm at work right now so I don't have all the stats on what jets, hangars and metering rod's I'm using- but I can tell you the carb has recently been blueprinted by the guidelines in your book and is a 750 cfm unit sitting on a street/strip Buick 350 engine.

Issue 1.
-Happens cold and warm
-During idle while parked or driving
If I increase throttle very slightly, maybe 2-15%, it completely falls on it's face to the point where sometimes it will die.

Issue 2.
After a high revving situation, like coming out of a burnout box- when I let off the gas from heating the tires- sometimes it will die.

Under ANY other circumstance the carb runs like a dream.

I've tried smaller jets and smaller primary metering rods to help with problem #1, and if anything it got slightly worse. The car flooded easily and since it ran so good at WOT I thought I might have a rich idle condition.

Thank you.

[429bbf]

CJ welcome aboard.  we need to know your carb no.it acts like your spring under your metering rods(if you have one ) is to weak .when you start to open the throttle there not allowing enough gas to make it speed up.on the top end  after you do your burnout there slamming shut .and the idle circuit doesnt have time to respond.hope this doesn't confuse you. dean

[CJB3884]

You're talking about the primary metering rods, right? If so, then yes there is one in there. When I had it apart a couple days ago I also made sure the round plastic pieces around the outside of the hangar that is above the spring was seated in its cavity snugly too. You think this is the same issue for both problems? I'll get you guys more stats tonight when I get home from work. Thanks.

[429bbf]

cj the most important thing when asking questions is the carb no.and  model (qjet -2 jet etc.) and then then engine and all the power train specs. that way people know what your working on and can give you a set up that is very close to what your working on.there are some very smart carb guys on this site and with a little patience your problem will be solved .example if your carb has an APT screw it may take 1 minute to fix your problem . screw the screw 1 turn ccwise one turn and give it a test run,on certain carbs this restricts the travel on the metering rods from going down to far.or you may need a stronger spring under metering rods (a vacumn guage is great for helping with this.)i tune with a vacumn guage in the front seat when im driving.i hook 6 ft of hose to a guage and run it threw the wing window.hope this helps. dean

[CJB3884]

Thanks guys. I fixed the off idle stumble. I took the "new" accelerator pump out that came with the carb when I had it rebuilt and put an old one I had laying around in it and it's ran perfect every since.

While I'm doing carb work though I need to fix a lean condition I have, and I'm not sure how far to richen it up. I pulled spark plugs from both sides of the block and although I don't have pictures of them the electrodes had an almost white chalky look to them.

Here the stats on my carb and engine:
Carb# 7043244 LD
                     2432
73 Jets
.045 primary rods
.0527 secondary rods

Engine: 1972- 361 c.i. Buick, 10:1 compression, .454 lift comp cam, super comp headers, no head porting done- but all new valve springs, rocker arms, lifters, pushrods, etc, msd hei ignition.

Transmission: TH350

Rear end: 10 bolt BOP, Eaton posi, 3.23 gears

[Cliff Ruggles]

I would install one of our complete accl pump assemblies, it comes with new springs and upgraded seal.  They are designed for this new fuel, and will improve accl pump performance.

Wrong jets and metering rods for that carburetor number.  I'm pretty sure the 244 carburetors used much smaller MAB's and smaller jets and metering rods.  The last one I built here had .068" main jets in it, and showed right on the money when we tested it.

Was the carburetor modified and re-jetted at some point?.....Cliff