MR2 SpyderChat banner

1 - 5 of 5 Posts

·
Registered
Joined
·
2,531 Posts
Discussion Starter #1
I was reading drummerdawg's swap thread the other day about his vibe motor with the blue injectors. Someone was saying that the Celica GT's use higher-flow yellow injectors than our stock green ones. Is there any benefit to going larger w/ a stock ecu?
 

·
Registered
Joined
·
326 Posts
I doubt it
 

·
Registered
Joined
·
9,742 Posts
can't go any injectors without something to control it. and then if you do get something to control the bigger injectors, does you engine have a need for more fuel? meaning are you getting close to maxing out your stockers?
 

·
Registered
Joined
·
2,531 Posts
Discussion Starter #4
can't go any injectors without something to control it. and then if you do get something to control the bigger injectors, does you engine have a need for more fuel? meaning are you getting close to maxing out your stockers?
I understand what you are saying here. I'm no where near maxing out the stockers, I was just curious why the different injectors were being used on both the Spyder and the GT since they have the same power output. This is a learning thread for me. :)
 

·
Premium Member
Joined
·
6,097 Posts
Is there any benefit to going larger w/ a stock ecu?
Ecu doesn't know what size injectors you have, it just gives timed opening pulses. If you swap bigger injectors in, the timed pulses are still the same, but the bigger injectors flow more during the same time, which just causes you to run bloody rich. Or not run at all, if they are big enough.

O2 feedback can correct some, but it's not really meant for that. That's why you need a programmable ECU with bigger injectors, like the PFC, or at least a piggyback like e-Manage. And even they have no way to see the injector sizes, you have to tell them.





Back to the question. Sometimes you CAN use bigger injectors with a stock ecu, if you also swap the MAF/MAP accordingly. That way the ecu sees false airflow, but uses the wrong sized injectors to actually make the AFR good. For example some Lexus MAF with xcc injectors work like that for Supras. I don't know if there is a working combination to replace our MAF.
 
1 - 5 of 5 Posts
Top