I read some topics on other forums about adding 10k ohms resistor to IAT sensor wirring. The idea is to fool ECU that intake air temperature is lower so it will send more fuel to injectors. Some guys swear that richer mixture gives more power and smoother engine operation.
Has anyone done it and what do you guys think of it?
Halibag or Thomohawk would have a definitive answer to that question, not I though.
Older twin exhaust models run a bit rich and younger one exhaust models are running a bit lean (16 vs 32 bit ecu).
And what is your richer mixture, do you have any AFR readings?
I run my 14 a bit too rich, AFR around 12 under the boost, for safety reasons, necessary or not.
For emission reasons under light load up to 3000 RPM the 14 runs a bit lean. Many dealerships will agree to set the A/F higher in that range usually reminding you that it is illegal. The IAT mod should help there for it to run smoother. In other ranges it may make it run too rich and may cause a wash out of the oil layer in the cylinders and a dilution of the oil in general.
This was a mod I did on an older BMW GS1200 I owned a while back.
It certainly made a difference to low speed pick up and gentle roll on throttle response / smoothness.
Never thought of doing that mod to Sophie.
S.
And what is your richer mixture, do you have any AFR readings?
No, I don't have any AFR readings.
Without AFR readings (or at least CO readings) it's a guessing game.
Quote from: Andre on Tuesday, 02 July 2019, 04:02 PM
Without AFR readings (or at least CO readings) it's a guessing game.
Thanks Andre!
Your welcome :)
There are better (and expensive) options:
Power Commander
Direct ECU modification:
For 16-bit (older models with single ECU connector) Yoshimura box or clone (Nikko Fuel Injection Adjuster) Very basic fuel adjustments but enough for many cases)
For 32-bit (two ECU connector) http://www.woolichracing.com/products/suzuki/gsx-1400/0/704/2004-2008-suzuki-gsx-1400-usb-mitsubishi-v3-package.aspx (http://www.woolichracing.com/products/suzuki/gsx-1400/0/704/2004-2008-suzuki-gsx-1400-usb-mitsubishi-v3-package.aspx) or Yoshimura box
Maybe others.
You just have to find a place that has the tools and does it. Or buy and do it yourself with AFR sensor and preferable(?) a dyno.
Be interesting if anyone tries this mod and reports back. I did think about sticky-ing this topic, but at the moment it seems more of a discussion? Sounds an interesting mod though!
Diavel runs lean up to 4k revs. Surges, easy to stall.Just a pig actually. In below 10 degree days its way improved, almost smooth. All to do with IAT making it richer. A common mod is to buy plug in device that tricks sensor to thinking its colder. $150 but guessing its just a resistor. My 14 is super smooth, no need to change.
I wouldn't.
My K2 has a custom map on & one thing it doesn't do is make the bike richer most of the time...
The numbers are a percentage of the original injector firing time & minus numbers are shorter firing, so leaner.
Not really knowing but just a thought. Im sure youll set me right. We add Power Commander, take it to dyno. Everything set at perfect A/F. This was done at a certain ambient temperature. Lets say 15 degrees C. Here we go down to 5 but up to 45. My thinking is IAT will change A/F ratio. Should IAT be dis abled to keep perfect A/F. Old days with carbs they basically stayed same with air temp. Not so with altitude.
Grog, if you disable IAT you won't keep "perfect" AFR as the amount of oxygen molecules per liter varies with temperature.
Andre, i said i wanted answers. Thank you.
Quote from: grog on Tuesday, 02 July 2019, 07:39 PM
Not really knowing but just a thought. Im sure youll set me right. We add Power Commander, take it to dyno. Everything set at perfect A/F. This was done at a certain ambient temperature. Lets say 15 degrees C. Here we go down to 5 but up to 45. My thinking is IAT will change A/F ratio. Should IAT be dis abled to keep perfect A/F. Old days with carbs they basically stayed same with air temp. Not so with altitude.
No as Andre said, air density varies with temp.
Also carbs did stay roughly the same for altitude, but the thinner air, being less dense, makes the mixture richer. On our bikes the pressure sensor on the RH side of the airbox allows for that & the ECU leans the mixture off as altitude increases to keep it running right.