Others have said the SUs are betterand I agree, a properly set up set is almost bullet-proof. They have to have good throttle plate spindle bushings or you can never get them right. The Weber carbs have often been slagged on this and other sites, I've never run them, but the fact that they get worse mileage than the SUs is enough for me. I know you asked about injection, but really in a 25+year old system you are asking for some headscratching. You should be able to have the SUs rebuilt for aprox.$150.00 and not have to worry about them for at least 5 yrs. When new the SUs are not hard to tune, When worn they are IMPOSSIBLE.