83 lbs injectors and FQS

[TTM]

Hello

Is it possible to use 83 lbs injectors with the usual Guru Racing chipset ?
The old Guru Racing instruction sheet mentions as far as 75 lbs units (FQS settings #3 or #7) but doesn't go further ?

Thanks.

 

[John Sims]

Does that atomise the fuel or just pump it in down a garden hose. []

#72's go to a very high state of tune. Are you sure you really need #83's

 

[TTM]

Yes, 83's sound definitely pretentious and I am pretty sure I do not need them, but the thing is they were included with the spares of my 3.0 engine, and since I found out a knock issue above 5k revs which may well be due to faulty injectors (on my current 2.5), I was wondering if I could fit the 83 lbs directly instead of having the original ones cleaned up.

 

[Diver944]

If your FQS switch doesn't have a setting specifically for 83lbs then it will overfuel dreadfully. If you had some sort of Piggyback or Motronic editor then you could scale down all the fuel cells accordingly, but with a simple chip set up for 72lb you will just be rich everywhere [&o]

 

[sawood12]

It's not just fuelling. The DME also contains ignition maps which may very well be different for different sized injectors - I don't know for sure but it is something i'd not be willing to take a punt on. If you really want to use the larger injectors then you're best getting new chips.