injector put in

[99 gst spyder]

just put in my 560cc injectors and i'm pretty sure i did it correctly.....when i get to 4k rpm, my car seems to stutter for a split sec, then normal while still stepping on gas....is this something that needs to be tune? before the injectors are in the car ran good when wot...just want to make sure that's the case that it might just need tune and that it's just pushing more fuel....is it pushing more fuel that's why it's doing that.....

 

[crimsondragon]

Were you expecting to just drop in bigger injectors while the ECU still thinks is running 450ccs and not expect something to go slightly wrong? Of course you need to tune it. Get an SAFC.

 

[90laserRSfwd]

Do you still have the Neo? If so did you use it to make the adjustments for the 560's?

 

[1992awdlaser]

Yes, it needs to be tuned. With those injectors and no tune you are flowing about 20% more fuel than stock. These cars already run very rich from the factory, sometimes dipping into the 9.x:1 air/fuel range. Adding 20% on top of that is only going to make it worse.

 

[Splitpi]

Not to mention the 560's injectors have a lower dead time than stock and so you'll need to tune the low hz air flow aswell.

 

[99 gst spyder]

alright... i'm in the process of being done with my setup then...heading to the dyno today and having them tune it and dyno....just want to make sure that's the reason why i'm having stutter after that injectors were in... tuning with afc neo...