6SSPEED

I have a 2000 z28 and recently maxed out the stock injectors so I bought some Lucas 38#. Before the injector swap the car was laying down 397hp. I changed the injectors, put bigger headers and a cutout and it dropped to 379hp after being retuned. The Lucas injectors are a pencil type spray pattern injector where as the stock ls1 style is a 4 hole spray pattern injector. Is the spray pattern what's costing me this power loss?

These are the injectors I installed......

Majestic9C1

iTrader: (19)

My sources say yes... but dont quote me

Lonnies Performance

iTrader: (16)

Not sure since you changed multiple things as 1 time....

Did you use the same dyno.... this is a key factor.
If not the numbers are meaningless.

Did the dyno operator correct for weather conditions?

Do you have a graph of the air/fuel ratio with both sets of injectors?

Did the same person tune it both times?

Larger headers generally help the peak power & lower the low end so they in theory should have raised the peak.

If you really want to know, change the injectors back & retune//test.
Its the only way you'll know

6SSPEED

Same tuner, same dyno. Yes, all corrections were made. I know the injectors are the problem but my real question is does the spray pattern really make that much of a difference or is the problem in the injector itself?

RJDio

Interesting thread, following it. I'm no where near maxing out injectors, but I just ordered a Racetronix fuel pump with hotwire. I hope to get to a point of maxing out injectors

S10xGN

iTrader: (11)

We're they flowed and cleaned, or did you just "stick 'em in" and run with it?

6SSPEED

Inspected them to make sure the tips weren't broke but didn't have them cleaned