Fuel injectors are rated by their pound per hour flow. This is the weight of the fuel that the single injector can flow in 1 hour. This is generally at 43.5 pounds of regulator pressure. This just happens to be the stock Fiero fuel pressure at the regulator, so it's really pretty easy for us to find the correct injector for our mods. Injectors can flow more per hour if the pressure is increased, but they also can reach their limit and begin to lean out. Generally you want to use 80% as the duty cycle rather than pushing them to the 95% range.
The injector requirement for any given engine is determined by the amount of horsepower the engine can produce at the flywheel and the number of cylinders the engine has. Thus, a 200 hp V6 will require a different size injector than a 200 hp V8 or a 200 hp 4 cylinder engine, even if the injectors appear identical on the outside.
Whether doing mods on a 2.8, upgrading to a 3.4 or installing one of the later V6 or V8 engines that are so popular for the Fiero, don't just take it for granted that you can use the same injectors that came in the engine. Dropping in a 3.4 will usually require a change from the 3.4's Rochester injectors if you retain the Fiero ECM. Fiero V6's used a pintle injector and the Fiero ECM is programmed to efficiently control them. You can upgrade to other brand injectors of the pintle style and get the needed lb/hr flow needed for the engine. These might be a suitable injector for a beefed up 2.8 or for a stock 3.4 upgrade.
BMW Fuel Injector (M50 S50 M52 S52) - Bosch 13641730060. Use 0280150415 for flow reference. NEW Bosch "green tip" injector. These Bosch injectors with the green pintel cap indicate a 17lb rating. Upgrading to the popular 7730 ECM might also require a change in injectors. Do your research on the engine of the car your 7730 ECM comes from. Find out if it uses pintle or disk style injectors. Use this as information in selecting your new injectors. Talk with your injector source and get their recommendations for your particular application.
To aid you, here are a couple of links that I find to be chock full of information.
http://www.justfuelinjectors.com/servlet/the-template/efiflowchart/Page Link Dead
Also, use the Categories menu at the left to find good prices on rebuilt injectors and throttle body injectors.
A good injector size calculator can be found at the top of the page at
http://www.fuelinjectorconnection.com/index.html FIC sells new and rebuilt injectors as well as offering a rebuild and flow matching service. They can even modify the flow of your injectors.
EDIT: EDIT: EDIT: EDIT: JUNE 23, 2018
This information is now in the "3.4 swap into a 2.8 Fiero" thread but is worth repeating here.
This is what I found regarding Bosch Fuel Injectors # 0280150415. This comes from Injector Planet's website. They are specified for the BMW M3. They have a green body and pintle cap.
This is a modified pintle injector with a 4-hole nozzle. There is a pintle behind each nozzle hole. This creates a much better spray pattern for better atomization.
Bosch EV1 Fuel Injector
Jetronic port / 4 hole nozzle
Flow rates @ 43.5 psi / 3 bar
16.76 lb per hour (My Note: 17# rated injectors flow at approximately 16.666 lb/hr at 3 bar or 43.5 psi. See calculator chart below)
126.5 G per min. (N-Heptane)
176.1 cc per min
15.90 Ohm resistance
Note these numbers. Though the same Bosch part number I originally listed, the BMW part number has changed. This injector is for the BMW M3.Bosch Part # 0280150415
BMW part # 13641730060
CHART FROM MOTOR MAN FUEL INJECTOR SUPPLY
Fuel Injector Size Calculator
Horsepower (at the flywheel) 160
Number of Injectors 6
B.S.F.C. *
Max Duty Cycle in % 80
Required Injector Static Flow Rate @ 43.5 psi lb/hr 16.666
cc/min
Advertised flow rates can vary due to a number of variables. Note that Injector Planet specifies N-Heptane as the fluid used. There are about 3 others that may be used. Obviously, some of the fluids have similar properties as gasoline. According to several flow charts I've seen, petrol appears to give a higher flow rate than N-Heptane. Ohm rating is also a factor. These are within acceptable range of our stock injectors, so the ECM shouldn't have any problem with the pulse width. Duty cycle shouldn't be pushed past the 80% range as flow rate falls off. Raydar tells us that the ECM controls duty cycle and will adjust to the limits of it's programmed table, then the injector becomes unstable.
