Having reall problems. Seems to be running rich. But carb popping during load accelerating editing 2nd gear. Black exhaust pipe stains. Very bad exhaust fumes. So much carb popping on one carb inside black stains.
timing is correct. New plugs. Old ones dry but Black.any thoughts? Carb rebuild?
only 2000 miles on car. Although has sat up a good bit before I purchased.
Thank you
Paul
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@Phisaac posted:Having reall problems. Seems to be running rich. But carb popping during load accelerating editing 2nd gear. Black exhaust pipe stains. Very bad exhaust fumes. So much carb popping on one carb inside black stains.
timing is correct. New plugs. Old ones dry but Black.any thoughts? Carb rebuild?
only 2000 miles on car. Although has sat up a good bit before I purchased.
Thank you
Paul
My smoke is sooty black
Rust/dirt/crud/shmutz in the tank from sitting could have clogged the idle jets and possible other passages in the carbs. I'd try cleaning the idle jets first. That would at least tell you if that's the problem. The cure might involve cleaning out the fuel system. At the very least I'd expect new fuel filters.
Sitting is bad. I had a similar problem with mine when it sat while I tried to get it first registered with our lovely SC DMV. 
It was running when I parked it! They were pretty much all were. It don't mean they'll run now.
Redlineweber.com has a lot of free information. Download the IDF stuff. Read it and re-read it and read it again when you are working on the carburetors. Just like spaghetti sauce...it's in there.
EMPI carburetors are a copy of Weber 44's. If your car has setup for a while you'll need to rebuild the carburetors. Get new carb kits and be sure that the float needles have viton tips.
Check for air leaks at the intake manifolds below the carb bodies and at the connection to the heads. Check for air leaks in the exhaust headers at the heads and any other exhaust connections.
If you have a heavy smell of gas fumes in your garage you likely have a float that is not closing. You may also have gas in the oil. If you smell gas in the oil; change the oil immediately before running the engine. Be sure all oil is drained from the system if you have a remote filter and oil cooler.
Idle jets are a fairly constant issue. Remove the jets and blow air thru the orifice. You have to be able to see thru the jet. Be sure to replace the o-rings on the jet holders. Be sure that the old o-rings are not in the carb body. Also blow back thru the carb body where the jets were. If you don't have an air compressor you can buy canned air at Office Depot.
Install Jet Doctors. They do wonders, but you'll still have occasional idle jet blocking.
The float bowl is open to the atmosphere within the air filter. Nothing you can do about that.
The idle stop screws are never more than 1/2 turn in from contact with the arm. You will never get the carbs set right if they are set more than 1/2 turn.
Balance of the carbs is critical. They either work together or work against each other. They cannot be balanced with the carb linkage attached.
There have been volumes written about this issue here. Search the archives.
@Lane Anderson posted:Rust/dirt/crud/shmutz in the tank from sitting could have clogged the idle jets and possible other passages in the carbs. I'd try cleaning the idle jets first. That would at least tell you if that's the problem. The cure might involve cleaning out the fuel system. At the very least I'd expect new fuel filters.
Sitting is bad. I had a similar problem with mine when it sat while I tried to get it first registered with our lovely SC DMV.
After sitting who knows how long in FL, then being "restored," then sitting outside through 2 NY winters after I bought it, I probably soaked and swished close to a pound of rust flakes out of my tank over the first two years I really started driving it.
After leaving it sit with a coating of Gibbs Brand over two winters while I had the car apart for modifications, then replacing the fuel pump and filters, I think I've finally got it cured.
I'd say new filters and a carb rebuild would be a good start.
Check for air leaks at the intake manifolds below the carb bodies and at the connection to the heads. Check for air leaks in the exhaust headers at the heads and any other exhaust connections.
I've posted this tip before, but barring having an expensive smoke generator to do this, a stick of incense makes a great leak detection tool for checking this out.
Bonus: it smells good, too. 
With the car running, you can spray carb cleaner where the manifold meets the heads. If you hear the idle increase for a second, you have a leak.
Exactly what Jim Gilbert said.
I'll only add to remove the idle mixture screws, and blow carb cleaner through them. It will come out the idle jet holes. Then blast it through the other direction. A lot of times the idle circuit is full of junk, and cleaning the jet only gets the one chunk of gunk. There's usually plenty more where that came from.
In fact, remove the carbs, and take the tops off. My money is on white goo in the bowls, and everywhere else in the carbs. Clean them REALLY well. Rebuild and assemble.
Make sure you retain track of all washers, o-rings, and springs.
Okay guys just a little more help.
After doing everything else as suggested I rebuilt the carbs. Starts and idles well. Gas smell has all but disappeared. Although I am Still getting some popping from the #1-2 carb under load.
any suggestions?
as always thank you for your input.
Synch them.
What linkage are you using?
Did you get the Weber tuning guide?
How have you determined it's 1 & 2?
Does the popping start when you let off the gas?
Is the popping back thru the carburetor? Check for exhaust leaks.
Are the air by-pass needles closed?
Did you check for air leaks at all gaskets with spray carb cleaner? Spray anything that has an o-ring or gasket.
Proper tightening of the carb body screws does not mean trying to wring them off. Sequentially tighten the screws in a cross pattern, just snug and one more grunt.
All adjustment screws are lightly seated when screwed in. Not tite. There is no repairing a damaged carb body from over tightening the adjustment screws...as far as I know.
Idle jet blocking should not be a factor above 3,000 rpm.
Check the ignition timing.
Have you adjusted the valves?
Chasing the popping can be really annoying. The engine will run fine until you want to take it to a show. They never give any problems when you have no plans.
I'm one of those guys who wants to fix it NOW. Sometimes I find that if I just put it down for a few hours and then go back the problem gets resolved...what ever it is. Sometimes it doesn't.
Don't know what your abilities are, hopefully they trend toward mechanical. It's not rocket science, but can be tedious.
All things work together.
Careful, step by step will get it right.
"I am Still getting some popping from the #1-2 carb under load."
Spray some carb cleaner around where the carb mates to the manifold and again where the manifold mates to the head. I'm betting on a gasket leak. If it leaks, the idle speed should change when you spray it around the gasket intersection, but not always.
Did you use new gaskets on both ends of the intake manifold on that side?
