Priobe (and others):
Here is what I am currently running.
42mm chokes
65 idle jets/ 100 idle holders
165 mains/ F5 emulsion tubes/160 air correctors (Was using 170 mains on Jim's suggestion, but broke one so I went to 165s)
55 bypass valves
My Cam is Crane Cam #F-248/3334-12
Duration of 248 deg int/exh @ 0.050 lift
Lobe center 0f 110 deg, 24 deg overlap
454 ci center oiler with Edelbrock heads. MSD dist and 6AL with 20 deg intial and 38 deg total timing all in by 2800.
(Will be going to F11 tubes when I get a job so I can afford them. Will bring in mains a bit earlier that will work better with our light cars per Jim). May also go to a 60 bypass valve, but right now the 55 seems okay.
Decel backfire will be finally corrected when I get my job and can afford the Remflex gaskets for the collectors to eliminate the discovered exhaust leaks. (Made to go away by turning idle mixture screws a bit to cover the problem by running idle circuit a bit rich. No backfires but a bit sluggish down low.)
One big critical improvement that came from Jim was setting the float heights accurately. Struggled for years trying to do it the traditional way that has been described by all forever. Here is what Jim suggested and it worked easily and very well:
1. Make a gage to measure the 5.5 mm height of the float above the carb body. ( I made one out of plexiglass. You could have one made by a local machine shop if necessary).
2. Remove the cover screws on the 2 carbs on one side of the car with the exception of 2 screws per carb.
3. Run the car for about a minute or so to be sure that the fuel bowls are full.
4. Stop the car and remove the remaining screws. Carefully remove the 2 covers of the carbs.
5. Now measure the actual float level using your Go/No Go gage for the 5.5 mm height.
You will be able to see immediately if you are getting the correct on-the-car float height. This method accounts for the needle valve variations, etc. If needed just raise or lower the tang setting as needed. Replace the covers with the 2 screws per carb, start the car for a minute, shut off and check again. Repeat if necessary. When done - do the other side. It actually works very well, quickly and gives you a great sense of confidence that they are finally right!
Once I got the floats right and replaced the 0 bypass with the 55s, the hot carb drip has been greatly reduced to almost non-existent.
There you go! All I can say is - Thanks, Jim! If you talk to him - listen and do what he says. He has been there (with his "real" Cobra) and knows of what he speaks.
Let me know if I can help anyone.
