+20 and +40, those terms are outdated the second they came out, both need to be retired and people need to stop using them completely.

Injectors need to be rated by flow number either in lbs/hrs or cc/min at a given fuel pressure.


DDG- Injector Flow and Application charts

2.5TI/TII/TIII/TIV injectors = 33 lb/hr at 55psi (3.8bar)
+20 injectors = 42lbs at 55psi (3.8bar)
+40 injectors = 52lbs at 55psi (3.8bar)

The math is all wrong on +20 or +40 injectors, no matter how you do them.

(42-33)/33 = 27%
(42-33)/42 = 21%
(52-33)/33 = 57%
(52-33)/52 = 36%


What to know what an injector flow? Get its part number, search it on google.
http://www.witchhunter.com/injectordata1.php
http://injector-rehab.com/shop/Flow_Rates.html
and many more.

Need to calculator the injector flow at 3.8 bar instead of 3 bar? Use an online calculator.
http://www.witchhunter.com/injectorcalc1.php