Steve@Rennsport

Scott,

I think you have multiple issues,....

1) A catch can has no connection to how Webers will run. Thats only for dealing with crankcase and oil tank breathing and a catch can or tank breather is recommened. Without seeing your installation, I cannot offer anything further,..

2) Popping & backfiring is carb-related and you need to go through the whole installation and setup to solve that one. This means close attention to details such as clean fuel, fuel pressure, float level, and proper jetting. Further, the ignition system must be in PERFECT operating order and the valves all adjusted properly.

Steve it's Scott (Bavaria911) here,
Wondering if you know about what a Catch Can does for a Weber Carb motor. I recently drove the car to a work shop to get my Webers tuned and adjusted. The motor popped and backfired all the way to the shop. I noticed the oil guage was just ti=ouching the red color on full.
With the motor warmed up, I drove the car between 2000-3500 RPM with oil pressure between 2 to 4.5 (German guage says DRUCK from 2-10).
When I got to the shop to let my buddy hear the motor and webers popping at 4000 RPM, we noticed alot of oily mix dripping from the two hoses that mount to the K&N Watershead air filters.
What do you think is wrong: too much oil in tank, popping carbs pulling oil to the air filters, or did the previous mechanic hook-up the breather hoses incorrectly to the oil tank and K&N filters?
Will a catch can stop the oil from being sucked to the Webers?

TIA,
Scott