Can anyone tell me what size of fuel injector Pontiac used on their 1987 5.7 TPI GTA Trans Am? I would also like to know what the Bosch part number was and the fuel pressure as measured
on the fuel rail with and without the vacuum line connected.

Thanks,

 

Vance,

From what I have been able to gather, the stock injector is reported to have a rated flow of 22 lb/hr maximum output at an 80% duty cycle and 44 PSIG inlet pressure. The TPI design operating pressure specifications are 37 PSIG ±3 PSIG with 18" Hg applied to the regulator, 44 PSIG ±3 PSIG with 0" Hg at the regulator (no vacuum). System pressure variations, manufacturing variations, and ECM variatiosn can all skew those flow numbers one way or the other.

Incidentally, the 305 CI (5.0 L) TPI engines were similarly rated at 19 lb/hr.

If you have in-depth injector questions, check with Rich at Cruzin' Performance. He can probably even provide you with a list of the O.E.M. part numbers for your model and year. If you suspect you might have an injector flow or spray pattern problem(s), he is definitely the guy to talk to. I've used his services several times with nothing but complete satifaction. They can flow-match your set far better than the factory did, and for a ridiculously low cost.

(Damn, I should be getting a royaly for this...)

 

Thr GM Delco p/n for the 22# injector is 17111961. These were
made by Bosch for GM.

 

To: Z28DJP1987

The part number printed on my Bosch injectors is
280-150-759. These are actually listed as 21.8# but I have
been told they will flow at 24# if set for 43 psi. I would like
to find out what the Bosch part number (not GM) for the stock
22# injecters.

Vance

 

Vance
Well since you have the Bosch P/N, don't try a GM parts counter.
Because they are going to ask for the GM P/N.
Good Luck in your quest.

 

Im getting a supercharger this summer and i realized that i need at least 24lb injectors and i only have some cheesy 20.8 lb inejectors made by rochester, im looking at the accel 30lb ones for $250 from summit, any suggestions or comments on these injectors thanks in advance for the help

 

Just be sure to have a new chip in before you run 30lb injectors in there

 

go for the frod racing 30's.... they are cheaper and flow the same

 

are they the pintle design for increased atomization