MSefi.com read only forum (Jan.15,2018)

Hey all,
I've got a fairly mild 250 Chevy six with 3 39lb. injectors - one for each siamesed port. The req_fuel calculator sets me up at 11.7 with 6 squirts per engine cycle. The bottom number comes in around 3.7-ish.

Ok, fine, starts and runs decent. Loses power at mid-high throttle. So I set the req_fuel to 15 which sets the bottom # to 5.
Runs much better now.

Question is, am I sacrificing idle (going too rich) to get decent power? Or will the narrow-band O2 handle that? I'm going for a daily family hauler, not drag racing.

Should I even adjust req_fuel at all? I don't know if I'm doing the right thing or not.

Thanks!
John

Req_Fuel is a base pulse width, but I would leave it at the recommended setting and then adjust the VE table as needed.

Thanks Matt, I'll try that. I'm not sure where to start with the VE table adjustments.

Do what Matt says - he is the man.

And yes use req fuel and then use your VE to enrich or lean. Look at your VE table while running and keep moving the values down in the idle area until it leans out (remember, idle areas are weird and based on manifold vac and so forth you may need it rich to idle nicely, if you are letting the O2 correct you may want to move the threshold for correction up out of the idle bin areas and let it run open loop to say 1400 rpm or so - bascially let it correct once you are out of the idle zone).

414cid