Ok guys ive been reading these boards for months, and everyone makes this tuning thing sound easy. I denfinatly picked the wrong engine to start tuning on. I have been chaseing my VE tables all over the place. I read somewhere that the stock injectors would have problems fueling my setup so I took a set of injectors out of a 91 z71. I assumed these were just regular 350 injectors, so I copied the injector constraints out of another bin from a 350. Last night I looked at the part number on the injectors and it reads 17084327. From what I can tell these are the 5.7 cop car injectors.
So my questions are:
Is these infact the cop car injectors and are they too big for my setup(highest duty cycle ive seen is 20%)?
would it be better to go back to the stock injectors @ 13 psi (as high as my pump will go)?

93 chevy s10 4x4 4.3L 4l60e

2001 4.3 block bored .030 over
2 valve relief flat top graphite coated hyperT pistons
ported and polished Vortec heads with cut spring pockets
Comp Cam's 266 hydralic roller cam
Comp Cam's 1.52 roller tip rockers
TBI with the Ultimate TBI mods performed
17084327 injectors
cold air intake
edelbrock 2114 intake
heddman long tube hedders
inovative wideband o2
moates autoprom
16168625 ecu $e6 mask
crane hi6 CDI ignition
SF ignition coil
dual efans

 

sounds like you need to drop down to the 55's


Engine | Bore ~~~|FI color| Flow ~~~| Part #
_________________________________________________
2.8L~~ | 1-3/8 ~~|Blk/Wht |33 lb/hr |GM5235430*RPD
_________________________________________________
4.3L~~ | 1-11/16 |Yel/Blu |45 lb/hr |GM5235203*RPD
_________________________________________________
5.0L~~ | 1-11/16 |Grn/Wht |40 lb/hr |GM5235279*RPD
_________________________________________________
Pickup
5.7L~~ | 1-11/16 |Orn/Blk |55 lb/hr |GM5235206*RPD
_________________________________________________
Cop car
5.7L ~~|1-11/16 ~|Yel/Brn |65 lb/hr |17084327-ACR
_________________________________________________
Late big block pickup
7.4L ~~| 2" ~~~~~|Blu/Blk |80 lb/hr |GM1708430*RPD
_________________________________________________
big block pickup
7.4L ~~|2"|Drk Red/Drk Blu|90 lb/hr|GM5235231*RPD

 

All but one entry of this chart is incorrect. With the correct entry being the cop car injectors.

As for whether they are too big for your engine, the maximum seen DC% with the proper observed AFR will tell you. Note that most stock 4.3l engines used 46 #/hr injectors. Some had staggered flow rates.

Which puts the 65#/hr injectors at about 30% more flow.

RBob.