what does a good running dsm's AFR look like

[dboyle23]

So I have tried tuning my car with no good results.

I am just wondering, on a car with a good tune, or a stock car, what will the AFR do when it's started cold? Is it immediately ~14.7 or is it richer or leaner? How much does the AFR change from open loop to closed loop?

 

[RvlutionMtrsprt]

14.7 at idle, 11.0 in boost is generally fine, leaner than 11.5 and you might want to take a look at things. Stock fuel map is in the 10's though. I can look at a stock 2g map and let you know specifics if you have a specific load point and rpm that you're wondering about. Is your car doing something that you don't think it should be doing? And what are you tuning it with?

 

[Colt4G63 also]

Mine isn't stock, but it goes right to 14.7ish at startup. If you have any leaks in your exhaust your readings may vary by quite a bit.

 

[Dioxine]

Im running a stock MAP and mine runs 15.1 at idle and 10 at boost but i have 272 cams and a small exhaust leak

 

[richard5309]

i just got mine and had to replace the o2 sensors, plug wires and plugs and the AFR gauge (everyone tells me to get rid of it but it was on the car when i bought it) runs FULL rich uner full boost....wtf?

 

[dboyle23]

Well, I have been trying to tune with ecuflash. But my idle changes all the time.

At startup its way lean, then super rich, then it gets to normal, then rich again. It's all over .

So, 14.7 is what it is aiming for at idle. If you start it cold, does it go to the 14.7 range immediately?

I hear some ticking at my o2 to downpipe, maybe I have a leak there.

 

[nightmares GS-T]

Guys just like colt already mentioned ANY exhaust leak before the sensor can throw the reading off so get the leaks fixed.

 

[milby43]

Hey, Id rather not start another thread. But I took a trip down the shore, and was testing out my new wideband. So when id get in it, i would going as rich as 10.1

Now, I do have a 16g on 14-15psi, and a walbro 255. I heard the walbro 255 can make me run really rich.

But can I correct that in SAFC?

 

[iBoostDSM]

A 255 is to much for the stock FPR. You need to get an AFPR to bring the fuel pressure back down which would also bring that 10.1 to a 14.7.

 

[milby43]

A 255 is to much for the stock FPR. You need to get an AFPR to bring the fuel pressure back down which would also bring that 10.1 to a 14.7.

Okay thanks alot man. I just been getting into tuning. Cause im gonna be going to school for it.

Ill see if i can get afpr soon.

 

[boostNmetal]

It's common for the AFR's to run rich on a cold start. Once the wideband warms up and gives you a reading, 12 or 13's is common until engine coolant temps start to rise.

 

[bsbllfit7]

A 255 is to much for the stock FPR. You need to get an AFPR to bring the fuel pressure back down which would also bring that 10.1 to a 14.7.

false, you don't need a new FPR, if your stock one is over running just get another stock one!

 

[clipto]

I am Running a Walbro 255 stock fpr and runs fine. Along with that a set of 550cc injectors and afc. My idle is 14:0 and WOT is 10.4 everyone setup is different depends on what you got. Most people tend to put 14.7 at idle and 11:1 at boost, but my friend cruises at 16.7, so in many cases I have seen it depends on the setup.