I have just installed in my 122 a fully rebuilt B20F (fuel injected head). I plugged the injecter ports to install a rebuilt SU's and am having a heak of a time getting this engine to run correctly. I have adjusted the valves and timing but can't adjust these SU's (if that's the problem). I have an electronic ignition so the points are not a problem. The SU are rebuilt but they can't seem to be adjusted for correct performance! The mixture and idle are set and everything seems fine but its another thing down the road! My exhaust "POPS" (no backfiring) and the car sputters like crazy. It as if when taking off the engine is starving for fuel yet everythings seems adjusted properly at idle. I have replaced the fuel filture and the floats in the carbs are adjusted and set properly. Question: Do I need richer needles with this Fuel Injected Head??? Or should I just adjust these stock needles richer? But, another thing is the spark plugs a carboned up and black upon inspection. If I set the carbs "leaner" it seems to run worse than before. Question: Would a set of "hotter" plugs help? Hopefully I have explained the problem so someone can help! Any help is much appreciated!