Fuel Injector Mapping
Posted: Thu Sep 17, 2015 11:42 pm
Sorry for this newbie question but we all have to start somewhere right? I've already read through the 3 main pdfs and couldn't find a straight answer.
Car is a '90 GTS-t with an RB20, Nistune is on a matching RB20 ECU. Have a couple of modifications but for purposes of the tune, it's only has new Injector Dynamics 725cc's. To start my tune off I just took the stock map and did the automatic injector rescaling while ticking all 3 boxes (load max, cranking tables, TIM/TID). From stock 270cc's to 725cc's brought the TIM from 512 to 190. Starting the car like this made it run very lean around 16-20 and it would knock. I adjusted the TIM to 290 to get it to stoichiometric with the short and long term fueling very close to 0.
Is it normal to see only a moderate drop in TIM with injectors almost 3x as big?
My AFRs also jump around a lot since going to these injectors with a +/- 0.5 while my stock ones only had at most a +/- 0.2. I gave ID a call and they said a range of 1.0 is not terrible or uncommon. Just want to hear it from another mouth that confirms this. Latency values were grabbed from their website.
Car is a '90 GTS-t with an RB20, Nistune is on a matching RB20 ECU. Have a couple of modifications but for purposes of the tune, it's only has new Injector Dynamics 725cc's. To start my tune off I just took the stock map and did the automatic injector rescaling while ticking all 3 boxes (load max, cranking tables, TIM/TID). From stock 270cc's to 725cc's brought the TIM from 512 to 190. Starting the car like this made it run very lean around 16-20 and it would knock. I adjusted the TIM to 290 to get it to stoichiometric with the short and long term fueling very close to 0.
Is it normal to see only a moderate drop in TIM with injectors almost 3x as big?
My AFRs also jump around a lot since going to these injectors with a +/- 0.5 while my stock ones only had at most a +/- 0.2. I gave ID a call and they said a range of 1.0 is not terrible or uncommon. Just want to hear it from another mouth that confirms this. Latency values were grabbed from their website.