I'll jump in on this thread being that I have Dual Quads, have a close RB setup, and I live in the EU..

Are your carb's dialed in exactly the same? Do you have both 600s (Which I think is over carb'd) with the same metering rods/jets? Did you follow the graph in the Edelbrock manual with the steps left and right / up and down to get exactly where you need to be? Before I installed my Dual Quad I knew I was going to need an Air/Fuel Meter. Wideband. If you can integrate that on to your exhaust you will be able to see exactly where you need to go with those numbers. I run an Isky 280MegaCam, Dual 500s in a Progressive setup. 440 has a mechanical advance Distributor, Initial is set to 16º, the bushing on my distributor is 18º so I get the full 34º by about 2600rpm (I don't remember the springs in the distributor to be honest...I have set it once...and I don't open it anymore). I do have the benefit of the Timing Advance dial so I can start my engine cold with about 48º....and then zero her back down when she warms up to the 34º so everything is at the distributor.

As for the fuel concerns, I dunno how Poland is. Greece is crap with fuel...I run the standard 95 Octane even though I built the engine to run on California's 89 Octane. Still, the 95 they sell here is more than likely crap no matter where you go but I will never fill up at Avin, BP, Or Shell. If you have it, I use EKO or RevOil.

Your best friend for that setup is going to be an air/fuel meter though. You can run a data logger if you want but I was dialing my engine 3 years back when I slipped the CH-28 on along with the aluminum cylinder heads. Took me about 2 weeks to do ($10/gallon) but I finally got her where I wanted her.

P.S. Sucks about the daytime lights requirement...Luckily we don't have that issue here, but then again, I am on Classic car plates and I would be exempt from such laws