Larger Fuel Injectors for 1UZFE...

[stevechumo]

I'm wondering if the stock SC400 ECU can compensate for the 315 cc/min injectors. That's around 26% more than stock. I know as a rule of thumb, most stock ECU can compensate for about 20%. Did anyone try it? How's the idle?

Any info if appreciated.

 

[MightyAl]

With the Mk3 supra we used to put 550s in but used an SC400 MAF that was 25% bigger then stock. Even then they would run very rich as the stock ecu would run rich with the 440s. Some people have tried to use a bypass valve to let in unmetered air to compensate. The ecu will try to compensate during closed loop but once it kicks into open loop it will get real rich.

 

[Lextreme II]

According to the 20% rule, your max injectors size would be 301.2 cc. I would stick with something below 315 cc.

 

[stevechumo]

The 315 cc injectors are a bit more tempted, but the 295 cc injectors sound to be more promising. I've run 315 cc injectors in several Honda that use 250 cc injectors. The idle is normal but the initial engine starting takes longer than normal. I really wanted to go for the 2 additional injectors with the Split Second, but I eventually ran into some really cheap 315 cc and 295 injectors. This drives me nuts.

 

[Lextreme II]

Well,

If you are going to use Split Second, then you can use alot larger. Got for 460cc.