Chupakabra-King

Is there anyone running 19lb injectors on a 350 ? The reason I ask is i have 19lb injectors from my 305 tpi and I will be installing a zz4 engine in a few weeks . Now the base will be siamesed and ported , ported plenum and larger runners . Can you just up the fuel pressure to accomodate the engine ? OR will I need at least 22lb injectors ?

Thanks for the info fellas !


Joe

Ed Maher

Since you have an 86, your car is MAF. Whatever you decide to use, the injectors have to match the chip. If you plan on using the stock chip, you have to use the stock size injectors.

19s could support such an engine barely, but you'd be much better off picking up a set of used LS1/LT1 injectors for $50-100 and getting a chip burned for them

Steve89GTA

According to Scoggin Dickey, 19's will be fine in a MAF setup on anything around 375hp and below. They also assured me that Edelbrock uses 19's on their 350's without a problem. I'd simply try it out and see how it goes. Take it to a shop with a wideband and run on a dyno. If it starts to lean out...see if upping the fuel pressure relieves it while watching the duty cycle of the injectors. If the injectors are maxing out and/or your fuel pressure is way high, you'll need to step up to 22's and make the appropriate change within your prom (namely, your injector constant to accomodate the higher flow). Simply changing the injectors will have your ecm OVER compensate for the lean condition (if it exists).