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Hi Guys,

I'm just wondering if anyone might be able to double check my maths from the Kinjflow calculator.

I've just swapped over from standard Bosch 960 injectors on my VR to 775 Blue tops.

However in the kinjflow calculator I'm getting a grams per second rate of 0.116 which is less than the OEM injectors in the standard 11P tune.

0 280 150 960 (EV1)
19.92 LB/HR 204 CC/MIN 150.58 G/MIN 14.5 Ohm 3.0bar OP

0 280 150 775 (EV1)
25.9 LB/HR 265 CC/MIN 195.79 G/MIN 15.9 Ohm 3.3Bar OP

I'd have thought comparing the two injectors that the grams per second injector flow rate would have been higher than the OEM injectors considering the G/MIN is higher and the LB/HR is higher?

Am I missing something here?

The other question is, should I be adjusting my base pressure on my regulator to 3.3bar from the standard 3 bar and is there also anything else I need to update in the tune other than the injector flow rate?

Engine is a 304, adjustable regulator.


Thanks in advance everyone, just starting to wrap my head around the fuelling side of things.

That looks right. Bigger injectors need a smaller number than smaller injectors with nothing else changed on the engine. Otherwise if you leave the value the same, it will flood the engine.

Also you need to look at the cranking pulse tables, that uses raw PW vs temp for cranking and the kinjflow doesn't factor in at all. There is also a min BPW value that you need to make sure is lower than any of the cranking table's values, otherwise it will also flood. This one caught me the first time and no eone seemed to know on the forum at the time, so it was a lot of head scratching.

Thanks Vlad, much appreciated!

No worries!

The other thing I forgot to mention is, don't stress about the kinjflow figure too much as most of the time you will need to tweak it some once you get a good idea on where the VE table wants to be. You want the peak VE to be around 90% up to 95%. As you tune, you adjust the kinjflow and adjust the whole VE by the same % until you get that 90 ish % VE and the kinjflow will be what it will be.


I personally don't use the calc, I adjust the kinjflow by the % difference from the old to new injector flow rate at the same DC and fuel pressure. Do the same for the crank tables.