jason's education thread

[Steve Wood]

Excellent point, Mike... You nailed it.

I recall one car with potentially high nine second parts that was stuck in the upper tens.  I looked at the wb vs the nb and the nb looked strange.  I asked about fuel pressure and the guy said he had not looked at it because the wb was right where he thought it should be.

Yep, he was running on alky because the pump was giving up half way down the strip. Turned out he had dialed up the alky twice because he had seen a little timing retard.   

WB numbers, or any other numbers, are only meaningful when taken in context and context is variable when we start changing the fuel up.  That is why I find it all interesting.

[good2win22]

Thanks for the input fella's.

Let me see if I got this:

No charts exist and if they did, it would be contingent on what brew was in the tank
More boost means less timing in high gear
Same boost means more timing in low gear
Switch to lambda when understanding and comprehension reach an acceptable understanding of it all

Going to tune for high gear mph and boost levels at my home test site then adjust that tune for low gear timing and fuel when at the track

[Steve Wood]

Not exactly

but the way I ramble, pretty close!

http://www.vortexbuicks-etc.com/basics.htm

Look at the O2 section at the top of the page and see if the graphs and words make the subject more meaningful

With regard to boost, I was suggesting that boost trumps timing and that on pump gas/alky, you will probably go faster by adding boost and subtracting timing if that is what it takes to run the boost without timing retard.  I'm pretty sure the same will happen on race gas as well from my own experiences.

In low gear, more timing may be required to get the turbo spooled faster but the event is so quick that it will not necessarily lead to detonation in higher gears if the timing has been reduced.  This applies with any fuel but is much more noticeable when spraying alky.  Too expand upon that and make it even more complicated, you may need to lean the mixture way down in low as well as well as delay the point where the alky begins to spray--all in the name of getting enough heat to spool the turbo.  You can do this in low because not only is the chamber not hot, but also because the load on the engine is low due to the gearing and the converter slip.

And finally, use this advice and other people's setting as guide lines but find out what works in your car under given conditions no matter whether your settings agree with common knowledge or not...not a bad idea to write them down for future reference.

[Steve Wood]

another comment, some of us old timers used to find that our cars slowed down on C16 and did not want to spool under certain climatic conditions.  If we poured some 110 octane into the tank with the C16, the car would jump out of the hole.  C16 seemed to be harder to get started burning under certain conditions whereas the 110 would burn much easier and get the car moving.  I suspect a lot of used C16 when it was not really needed in our combinations but all the cool guys used it so....LOL

[Steve Wood]

Another comment, aluminum heads are thermally inefficient with regard to the combustion process as they do not retain as much of the heat from the burn and heat is what makes hp.  A rule of thumb is that if we add about a point of compression ratio, we get back to approximately where we would be if we had iron heads.  If we do not have the ability to add some compression back, then we can use more timing and more boost to make the heat.

More in the sense of what we would be able to use in an iron headed engine with all else being equal...like cam profile, etc.  Some combustion chambers can be improved with regard to flame distribution, quench, etc so again...no simple answers, just more tuning.

When it comes to heat transfer into the coolant stream, they are more efficient so we may see higher coolant temps that we had with the iron heads. 

The big benefit of aluminum is that we may be able to cast/port larger intake and exhaust passages for more flow on top end and ultimately get more power at higher rpm on top end...it's up to us to make up for whatever we may have lost due to the poor thermal efficiency in the combustion process on the bottom end....

[good2win22]

Thanks again Steve.  I printed all the "basics" from your site shortly after I bought my first turbo regal.  I need to go back and read them all again.

The graph makes a little more sense to me now between the two sensors.  I watched both sensors at idle and at cruise with varying numbers.  800-ish at idle nb and 13.1-13.6 wb.  At cruise, 400-600 nb and 15.5-16.1.  My chips are not SD so I'm still tuning with the NB.  I may make take that step next year. Right now I'm in the monitoring/learning mode.

How can you tell when a wide band sensor is going bad?  I read that they stick on one side, usually lean.  Any truth to that?

[Steve Wood]

I don't think so.  Since last fall, I have been trying to figure out why William's car seemed to be adding fuel thru the blm block on his 6.1 chip.  The o2 looked nice and flat but the chip said it was pegging out the amount of fuel it could add and his injector numbers were high.  He went to 80 lb injectors and it helped a little, but his car was using more fuel than I thought it should. It should have been fine with 60's/

He disconnected the wb sensor and let it reset...no change.  Car looked okay at idle and cruise.  The other day, he said something about using race fuel last year to see if the car did any better.  It was one of those "Oh S***" moments.  I told him to get another wb sensor and sure nuf, suddenly it stopped adding nearly as much fuel.  Now I understand why his car was not detonating with a/f's 11 to 11.2 smh....

That was a Bosch sensor in an AEM wb system.  Bosch sensors are known for being sensitive to lead and high temperature whereas the NGK sensors last much longer.  That's why FAST and such use NGK.

Sensor looked normal to me...but it took a bolt of lightning to figure out the real problem. Car has picked up a tenth or two at best.

[Steve Wood]

at Cruise, my cars run about 010-020 on the o2s.  That puts them around 15.7 on the AF.  I have run 000 and taken out more fuel and cruised at almost 17-1.

I have read a car will not run that lean...I guess Buicks are more special than we know

[good2win22]

That was a Bosch sensor in an AEM wb system.  Bosch sensors are known for being sensitive to lead and high temperature whereas the NGK sensors last much longer.  That's why FAST and such use NGK.

Sensor looked normal to me...but it took a bolt of lightning to figure out the real problem. Car has picked up a tenth or two at best.

I wish I would've read that before buying an AEM wideband. Maybe why there so cheap.

[Steve Wood]

Stay away from lead and all should be goof

[motorhead]

Bosch has a new sensor, 4.9 if I remember right, vs. the old 4.2; the new unit is supposed to be much more robust.  That being said I was still on the original (ten year old) Bosch sensor that came with the LC1 in my Buick when I sold it.  I am running the 4.2 sensors with the MTX-L in my LSx cars since they are only used for logging - I've replaced the one in the TBSS once so far.

If you go SD and depend on the sensor spend the money one a good WBO2 setup.

[Steve Wood]

I have not seen anything concerning it's reliability when leaded fuel is used.  It is supposed to stay accurate longer when used with unleaded fuel and is driving the fueling control.

The 4.2 is cheaper by a substantial margin than the NGK sensor but has always been known to be much more susceptible to lead and egt.  They never lasted long when either using leaded or placed close to the turbo.

It used to be suggested to recalibrate them before each racing session when race gas was used, but, most of the new, cheaper systems don't have this calibration function built in.

[daveismissing]

Does anyone know if these Ballengers are as good as the originals?
http://bmotorsports.com/shop/

[1 RARE T]

To further drive home the point that not everyones' A/F ratio is/should be the same, my car always liked more fuel.

If I leaned it out to an 11ish ratio, it slowed down.

10.6 was the number spraying alky that it seemed to go quickest and felt strong. If you watch fast cars on the track,most are spewing black smoke at some point.

These guys are lucky to have your knowledge to "lean on". Get it? Thanks Steve.

Not having a TB any more for me is a shame but back when I did, I read your posts countless times 'till it sunk in.

[Steve Wood]

I have the original AFX which I bought when I gave up on Innovate.    I understand the Ballenger is very good but I would buy the one with the NTK sensor and not the Bosch.