I have purchased a used 454 TBI for use on a '98 350 Vortec. I am at odds on which injectors to use in the throttle body. Right now it has the 17104288 injectors but am uncertain as to their condition. Need to order replacement injectors. Have ordered adjustable fuel pressure regulator for the throttle body. Have two choices of injectors, the 17104288 or the 5235231. They are as follows from what I have found on the Internet. Also ordered a Bosch higher pressure fuel pump than the stock 15psi pump. Then should be able to adjust to some value pressure that should work. May have to purchase different poundage fuel regulator springs to accomplish this. There is a Vacuum referenced fuel pressure regulator available by way of Ebay. This seems to be counter productive to use as the ECM should make the fuel corrections via MAP values.

5235231 - Red / Blue - 80pph - 7.4L / 454 - 88-90

17104288 - Pink / Purple - 46pph @13psi - 7.4L / 454 - 94-95 *NOTE: Came with 30 PSI regulator used @ 26-32psi for 67-72pph

These flow rates are a safe bet average @ 12-13psi, be aware that actual flow can vary by greater than 10% throughout production.

Any advice or comments on this and course of action would be greatly appreciated.