Is my injector calculation sound

[sbn1979]

Right this is for Evo 6 - base map - fuel equation is traditional with master fuel at 12ms for stock 560cc injectors

542/1015=0.53

12*0.53=6.36

new master fuel, 6ms for id1000?

Enter relevant dead times in 2d table.....job done?

 

[Simon]

It will get you very close.

It will then be a case of just checking the mixtures through different loads.

Might be small differences between the injectors

[Anthony Parle]

Not sure I get were your coming from with the calcs

were did the 542 and 1015 come from?

[Scott]

Hi Tony,

The ID1000 injectors are listed as actually flowing 1015cc, and I expect that sbn1979 has some information that says the '560' injectors actually flow 542cc.

Scott

[Akmal747]

Hello scott...so for precision injector 1600cc what master fuel in ms?

[Scott]

Hi Akmal,

The correct master fuel number to use depends on the cylinder size. A cylinder of 650cc is going to want a lot more fuel than a cylinder of 300cc, so the same injector would need to be turned on for longer (higher master fuel value).

In the top post of this thread sbn1979 was using injectors that flowed 542cc/min and was using a master fuel value of 12ms. Using this data he was able to calculate the master fuel value to use for his new 1015cc/min injectors.

The calculation used was:

Ratio = current injector flow / new injector flow

New master fuel value = Ratio * current master fuel value

So if sbn1979 was upgrading to 1600cc/min injectors his new master fuel value would be:

542cc/1600cc = 0.33875

0.33875*12ms = 4.065ms

The master fuel value steps in 1ms steps, so 4ms would be the value to use. This calculation is useful for getting the master fuel value close to where it needs to be, the main fuel table would then want to be checked in each cell to make sure the value is correct.

Scott.

[Akmal747]

Thanks scott