NB sensor over 85 Kpa

[ViennaHog]

By 80kpa they are forced to go open loop, out of stoich

Wonder why?

Cars don't do this.....

cars do that as well. They use full throttle enrichment to keep the engine safe at sustained Autobahn speed

[wurk_truk]

(If I melt my motor, it would be my fault, as it is today if I damage anything with my tuning)

From Talking to Steve at the show, this is THE very reason we do not see this capability on VTune.  One would really need to check the data out forwards and backwards, mentally, before accepting the tune.  Problem would be an outlier COULD damage the engine and it WOULD take a careful review.  His feeling, from doing this awhile, is that not everyone would be careful and the product simply HAS to be designed for the 'lowest common denominator' kind of customer.  Look at ALL the warnings about MTEs, and even I didn't follow that fully on the rat bike.

I have to call BS on this one. It did not and does not stop Steve from selling units to  anyone with a pre o2 sensor bike where they can put in any ve number or AFR they dream up.

You calling BS on ME?  I sat there, at the show, and heard him pontificate on this very subject and I quote very well, thank you.

[strokerjlk]

lets say for example the motor happens to be lean at WOT assuming the base map has a "normal" Lambda/AF target of say 13.0 AF, what happens when you set the calibration to force closed loop @ stoich 14.6 AF so you can use the factory O2 sensors and run thru WOT to populate your corrections? ......there is a very good chance your already incorrect calibration will be running the motor @ 16.0:1 AF or even leaner, not to mention doing this under load at full throttle. That should answer alot of questions on this subject.

It happens at 30-80 kpa ,so anyone that has seen 16-17.0 at low map CL has to know it does the same at 80-100 kpa.
So lets say you get your Afr dialed in at 100kpa  @ shoich
Now what are you going to do about dialing timing in?
You have adjust Afr again once you make a timing adjustment.
It would be worthless AT this point to go back to stoich and try to dial Afr back in.
So in order to fine tune one you need to sample at the afr the motor is operating in.
If your just making the bike run and don't care to find its full potential a guy could use stoich to get it close. But the whole idea is to super tune one isn't it?

[ultraswede]

But the whole idea is to super tune one isn't it?

No, we are talking V-tune here......on the street

cars do that as well. They use full throttle enrichment to keep the engine safe at sustained Autobahn speed

Yes they do.
BUT I am talking about the tuning situation now.

[joe_lyons]

1fstrk[/quote]
Just curious how did you determine that 13:1 AFR makes best power?
[/quote]
I just picked 13 I could have done 13.5 also but I did not have the time to do a good full tune on the dyno. Just some quick runs to see where I was at.  I want to get my small o2 sensors done then do a full tune.

[strokerjlk]

Quote
But the whole idea is to super tune one isn't it?

No, we are talking V-tune here......on the street

LOL   I meant dial one in very well.
But I see your point

[Steve Cole]

wurk_truk quote me just fine. An O2 sensor has no idea what an engine is doing nor does it care. The decision to not allow for tuning above 84 kPa was a company decision here. We've been tuning EFI systems for over 25 years and we felt due to who all can use our product that was as far as we were willing to go. The ECM doesn't care as long as it is properly set up for it and just switching the table to closed loop is not all that needs to be done. There are plenty of things that can be done, provided you have enough data to support those decisions. With all the various builds we picked a point we felt would keep the risk to a level we were happy with.

If people are to look at data then make an adjustment, then repeat the process it is up to them and you can do it just as good with a narrow band sensor as you can with a Broad Band one as they are used today. Neither will be accurate but both will show you when the mixture is changing and which direction is leaner or richer.

[Jamie Long]

If people are to look at data then make an adjustment, then repeat the process it is up to them and you can do it just as good with a narrow band sensor as you can with a Broad Band one as they are used today. Neither will be accurate but both will show you when the mixture is changing and which direction is leaner or richer.

I dont think there is anyone that will agree with this statement

[BVHOG]

If people are to look at data then make an adjustment, then repeat the process it is up to them and you can do it just as good with a narrow band sensor as you can with a Broad Band one as they are used today. Neither will be accurate but both will show you when the mixture is changing and which direction is leaner or richer.

I dont think there is anyone that will agree with this statement

It was cool though how he got that little rip in on the broad band sensors while still not admitting he was wrong when TobeFrank showed him the correct math regarding the broad band accuracy.

[strokerjlk]

If people are to look at data then make an adjustment, then repeat the process it is up to them and you can do it just as good with a narrow band sensor as you can with a Broad Band one as they are used today. Neither will be accurate but both will show you when the mixture is changing and which direction is leaner or richer.

I dont think there is anyone that will agree with this statement

Not anyone that has ever done it more than once.
But I am sure there are those that still will agree.

[FLTRI]

Since we do not certify emissions the variations found between using these sensors do not preclude a tuner from getting the most from a build.

A tuner may not be able to quantify to the tenth AFR but the importance is in the end product not the absolute accuracy/number of the measuring equipment used.

Good conscientious servicing of measuring equipment provides very repeatable results which is the key to successful comparisons.

For over 20 years these Broadband (LSU4, etc) sensors have provided tuners with reliable, repeatable results when used in the AFR pumps as provided and tested by Dynojet.

Not convinced results from sampling in a pressurized exhaust pipe provides the same level of repeatability as the non-pressurized Dynojet pump.

But either way can produce great running bikes.

I prefer to use Dynojet's method...after all they've been developing dynos and tuning bikes everyday for many, many years and should know as much, if not more, than anyone else.

Just the way I see it from my personal experiences,
Bob

[ultraswede]

And still another thread drifting (excuse the pun) in to broadband sensors, even though BBs have nothing to do with the OPs (mine) question.
(My question was about > 84 Kpa tuning with NBs, as i n V-tuning.)