I'm wanting to change my old fuel spider injectors out for a new one I have a 2000 Blazer 4.3 W. engine I have been looking on line at some I'm getting confused about it.
What type of injection do I have? I want to upgrade it. (RockAuto.Com) They talk about SCPI Conversion to MFI, and on some I may need a bracket. Here is the info below of the ones I'm looking at.

STANDARD MOTOR PRODUCTS Part # FJ503
New; Bracket and Gasket Required But Not Included; SCPI Conversion to MFI, Replacement Poppet Nozzle available. Requires mounting gasket and Bracket.

$229.79 $0.00 $229.79

DELPHI Part # FJ10565
SCPI to MFI Conversion - Complete Assembly, May Require Bracket FH10098
$243.79 $0.00 $243.79


ACDELCO Part # 2173028 {Includes Instructions for Conversion from Poppet-Style Invectors #89060439}
INJECTOR KIT,CENTRAL SEQ M/PORT FUEL

$338.79 $0.00 $338.79

 

Fj503 includes everything you need to upgrade from the old poppet style injectors to the new design....

 

It says " Bracket and Gasket Required But Not Included; SCPI Conversion to MFI, Replacement Poppet Nozzle available. Requires mounting gasket and Bracket". Where do you see ever thing included?

 

I sell it and it always comes with everything even though
it says it doesn't

 

Is this a PERFORMANCE upgrade, or what type of upgrade is it?

I am getting teh occasional misfire and am told I need or will need a complete SPIDER assembly, but from what i can see online, and what was stated in this message by the OP, it seems there are complete spiders assemblies and a single injector...

does the new UPGRADE allow us to change just the injector???

also, isnt there any performance upgrades like larger injectors?

Cant we switch out the spider for individual injection systems? And when i say WE, i mean someone other then ME. hehehehe

 

I just replaced the spider unit in my 2000 Blazer with a 4.3W motor. I found an AC/Delco 217-3028 unit on amazon.com for $267.26. It was the MFI conversion, that included the bracket and all required gaskets. It's not a performance upgrade, it is a factory replacement to get away from the early unit that has popet valves at the end of the fuel tubes.
Quick note read the instalation instructions and make sure you start with #3 injector first.
It made a world of difference in my engines running issues.