i have 25 years working with fuel systems on classic volvo cars . so i guess ill reply to this one . old fuel inj can be a real problem at times unless you replace many of the parts relating to electronic or efi as we call it or j tronic. the system as it came on 1971 p1800 and 142e cars is a performing system when in proper tune, we race improved touring 71-142 w/fuel inj and it must be oem,with some success and reliability.but if you just want to enjoy your classic volvo and not spend lots of money then have joe curto rebuild your old su caurbs ,get a big valve fuely head and block of the inj holes . get quality 3 angle valve job . well on my 72 142s i did this fuel inj head w/su caurbs and i feel almost as strong as the b20f power in my 72 1800e . blueryder45@yahoo.com is dave spano cert.volvo tech cert.mercdes tech 25 years