Dyno?

[RETed]

Originally Posted by RICE RACING

Feel free to get some comments from the others here, but without seeing more information I say it lines up with the fuel mixture at those points being a contributing factor....... but like you say it is hard to diagnose from here.

I have to agree...

With my experience and what most people tend to do...
They try to run all "10's" across the board when it comes to AFR, just because they are paranoid of hurting something.
I tend to run my AFR's a tad leaner in those low RPM areas, cause the engine is still picking up steam.
Like I said before, detonation and engine damage is more likely to happen around peak torque.
I don't worry too much outside of + / - 1,000RPM's of the peak torque curve.
Just to pick up some responsiveness from the engine, I run the low RPM's areas prior to peak torque a little bit leaner and more aggressive on the total ignition advance.
Like I said before also, I keep adjusting the maps until the power lines stop climbing on the dyno - some people can't grasp this basic concept of tuning.
I have argued with idiots who claim: "oh, I can't go leaner than 10.5 AFR's because this other (questionable) tuner told me not to." [DOH!]
I have run some customer's cars in the 4kRPM region as lean as 11.0 - 11.5 AFR's on a dyno wideband, and the engine is happy.
(Keep in mind that every engine in each unique vehicle will be slightly different [in engine VE] no matter how much you try to duplicate a set-up, and this is why you need to tune each individually and maps will never be identical.)


-Ted