I just bought off eBay an old, but unused Holley 4 barrel throttle body. It has four Holley injectors labeled 250R-51AA and also 2074-43. I can't seem to find the specs on these. I realize that most folks upgrade to Delphi injectors, but given these are essentially new, I'm going to run them. My plan is to use a MegaSquirt, so I'm mainly concerned with flow rate, psi & impedance. Thanks.