need help with 550cc injectors

[jjannuzz]

I need some help with something ... First I will say what mods I have then what the problem is.

1992 Talon AWD
Evo 16g
Evo Ex. Manifold, 2g o2 housing
2 1/2" turbo back - Test Pipe
Super AFC I
2G MAF with Dejon Tool intake pipe
Dejon Tool 2.5" Piping From Turbo to Throtle Body including Modded Intercooler
Crushed BOV
Motor is all rebuilt
New Magnicore wires and ngk #7 plugs
Full throttle AFPR set at 38 PSI
255 Fuel pump (Not High Pressure)
New Fuel filter
I know these are not mods - Scanmaster 3 and I have no vacuum leakes (Checked 3 times)
OK Here we go. I installed brand new from Dejon tool 550CC injectors
Set SAFC to 0 across the board. Engine shakes and missies. Put 450's Back in and it runs fine. Check all wiring and pulse from injector harnes and all four are fine.
Put 550CC back in and runs like crap . I do this several times with no change. I try to tune out the miss with the SAFC but cannot . lean or rich it still misses

Also the Scanmaster pegs down to 60 on the o2 trim like it it so rich it is pouring the fuel in
But the 2g maf should have Compensated for this.

Am I missing something???









I put brand new 550cc injectors from Dejon Tool in my car. and it misses bad
tr

 

[BrokenTsi]

sounds to me like everything is working just fine. putting 550's in your car without compensating for it will do just that, run rich as hell. Keep leaning out the SAFC til it runs better. I would start out at -15 across the board and work from there.

 

[92awddsm]

With the 2g mas and 550 injectors, you need to lean idle up to -15 -18 range, low throttle about -10 across the board, and 0 high throttle. Just tune by knock. Lean it up till you get a little knock then richen it back about 1%. Tune idle and low throttle by fuel trims. This is how mine was set up at one point in the past.

 

[NOSLO2PT0]

The 2G MAS and 550's almost cancel out perfectly, when using the AFC. Shouldn't have to make any adjustments with this combination. Check the resistance across the terminals of the injector with a voltmeter. Should be between 2 and 3 ohms. Maybe you got a set of high impedance injectors by accident.

 

[heavyD]

The 2G MAS and 550's almost cancel out perfectly, when using the AFC. Shouldn't have to make any adjustments with this combination. Check the resistance across the terminals of the injector with a voltmeter. Should be between 2 and 3 ohms. Maybe you got a set of high impedance injectors by accident.

In theory they may cancel out but alot of real-life variables like altitude and temp, etc come into play plus no two DSM's are alike.