Once I get home I'll find the link for the injector chart table that tells you pretty much all of the info on every Bosch injector. I think you can go slightly above/below with the impedance but not massively different. The Saab reds have the same impedance as the standard AGU injectors but the C20LET yellows are a bit lower. They still work though and the reds have been fitted to Vauxhalls for years