I've rebuilt a few carbs and always seem to have trouble with them one way or another. I rebuilt the 5200 model, which is a Holley model (it's stamped on the carb anyway), and had it working perfectly I thought, but the engine wasn't running right. I ended up letting my dad attempt to tune it, since he kept insisting I had screwed the pooch rebuilding it. After he started working on it I figured out that my timing was one tooth out. The pointer didn't quite line up with the mark either way and apparently I had chosen poorly. After correcting that I could have torn the carb back apart and put it right, but it didn't matter because I had already ordered a replacement to shut him up about my carb rebuilding skills. The new replacement just kept flooding until I took it apart and reset it as well.
When it was all said and done, I changed the ignition out to improve the spark. It has been running much better since then.
I feel like fuel injection is the key if you want the best running engine possible, but it needs all the right sensor input to do it's job correctly. (My personal opinion anyway.) For the simplest setup I like the carb situation. I swapped the primary and secondary jets with a little reaming and like the results. Seems to run better for me anyway. I've taken it out now, but I had bent a spring to open both barrels at the same time and liked the way it worked then, but I wouldn't call it an economy improvement.
I have been considering moving the pivot point on the fuel acceleration pump for a bigger squirt on heavy throttle, but haven't talked to anyone else who has done it.
The biggest improvement came from just adjusting the linkage to the gas pedal to take out the play and make sure I was getting full throttle.
Removing the emissions devices (catalytic converter included) and going to 2" exhaust made it way louder.
I did read some interesting info though...
IGNITION
Distributors
Stock distributor should work well to approximately 7000-7500 RPM.
Dual point distributor should work well to approximately 7500-8000 RPM.
Unilite distributors will work well to approximately 8000-8500 RPM, MSD Distributors will reach 9000 RPM,
XDI crank fire ignition to 10,000+ RPM.
Suggestion: Total advance spark timing should be somewhere between 33 and 38 degrees. As a general rule, long rod
engines seem to like a bit more timing, somewhere between 38 and 40 degrees. Check total advance with engine
running at about 3500 RPM.
Spark Plugs
2.3 Champion RS9YC
2.0 Champion F9YC
Aluminum Head: Gasoline - NGK D7EA, Alcohol - Bosch XR2CS
Suggestion: Spark plug gap for all spark plugs = .030"
CARBURETORS
Carburetor basic starting point suggestions. These are just recommendation s to start with, you will need to experiment
from there.
5200 Weber
- Drill accelerator squirter hole to 0.030"
- Remove the jet in the secondary and place it in the main. Measure the size of the original secondary jet. Then select
a number drill that is two sizes larger than the original secondary jet size. Use that drill to drill out the old main jet.
Place the drilled out main jet in the secondary.
350 Holley
- 68 main jets
- 35 Power valve
- Holley off-road kit
500 Holley
- 70 Main jets
- 35 power valve
- Holley off-road kit
- If consistently fluttering out off the corners: use a holley power valve block-off and go up 2 sizes on the main jets and
change accelerator pump cam.
If you are experiencing problems with fluttering or loading up in the corners.
Step One: Install an off road kit(spring loaded needle/seat and vent whistle). Part#E3338
Step Two: Experiment with accelerator pump cams to lower the volume of fuel.
Step Three: If you replace the power valve, use a power valve block off (part# E3331) and go up two jet sizes,
after steps one and two.
From esslinger...
So, the question is really does this sound like fun? If it does, stick with a carb. If not, go find an efi setup.
If you want economy, I believe the manual transmission may be the better choice. If you want consistency with the car the automatic tranny seems to be the ticket. I'm sticking with the auto myself.
That's my two cents...