That is interesting - something similar happened to me when i last dynoed

from the logger It was sitting around 11.7 but the dyno guy was saying it was lean at about 12.5 . From then on I decided to play it safe and aim for around 11.4 -5 but I'm still not sure which is right as my ARF guage and logger pretty much line up perfectly but the dyno was different .

 

Yeah it seemed like for the most part that the AFR gauge on the AP is correct, but on the dyno it seemed to read about 1 point leaner. So therefore, it jacked up everything. But I was able to hold boost all the way to redline.

 

the afr readings from the AP has to be pretty accurate since it's coming from the pcm
I know with my aem wideband, sometimes it reads leaner than the ap..it's frustrating

 

8 psi right to the redline ? that is good , maybe the clipped turbine alleviates a lot of the issues i've had with the wastegate .

Let's see what it does at 10 psi

 

Don't forget, the wastegate is also around 15% bigger now......

S

 

which would logically make the problem worse if not for the clipped turbine

 

Yeah I was pretty impressed with it being able to hold the 8 pounds from 4k-8.5k

Oh I thought I would share that I logged 407 g/s at about 9-10 psi.

 

/\ you got 10psi to the redline with just boost controller adjustment ?

 

I didnt pay attention to if the 10 psi was held for how long, I was more excited about my engine load and g/s that I was reaching.

 

that's an impressive number but don't read too much into it till you get the dyno numbers to compare it with

 

Sounds good! Get that thing a new O2 sensor (preferably an NTK sensor). They are much faster than the cheapo Bosch UEGO.

 

Deviation from a known value.... it isn't exact but it is a pretty good idea or what is going on with the car.

Same thing - I think it has to do with location of the sniffer... My two widebands match - then I trust 'em.

See above - deviation from a known value.

I don't know what sensors are compatible with the PCM... Jeff might.

I just tend to go redundant systems - factory and an aftermarket wideband to be safe.

 

good numbers j.cab!

 

I am gonna dyno it again sometime in the next couple of weeks, somewhere else where I can turn up the boost past 8 psi, and not get grief from them...

Hopefully Kane will be done with my tune completely here this week....

Maybe I will treat myself for my birthday to a dyno on Sunday..

 

kool...keep us posted with more dyno numbers!

 

it happened to me one time when it was dynoed, and teh tuner looks at his AFR on teh computer is lean, but in my Wideband cobalt, it's richer. so, he tried to add fuel, and it was bugging, my Wideband was 10 and his was 11.5, so he realized that his filter, or someting on his machine, that he needs to change. after changing it, my Wideband and his almost the same. mine read 10.5, his is 10.7 ..just off by a few point....
steven

 

Yeah like I said it happend to me last Friday, so he was adding more fuel therefore making it rich as hell. So Kane and I are just about 99.9% done with my new tune. I just have to do one more datalog, and it should be good to go. Then I am going to dyno it again.

 

If the sniffers aren't put far enough into the pipe, it can get reversion air which can cause it to get a leaner mixture reading. Also leaky connections in your exhaust systems can alter readings. Old O2 sensors start reading lean shortly before they crap out.

 

I am just about to send my spare GReddy turbo out to Bryan.

Does this mean I will need a new custom tune for the upgraded BNR turbo?

 

yes.

beers

 

when is someone going to make some hp with one of these ????????????????????

 

Dyno is scheduled for this Tuesday at 630 pm pacific standard time.

 

Awesome!!! Can't wait.

 

Depends... how good is your tune now? You may need to fine tune - but if your MAF is spot on you should be pretty good. Unless you change intake / injectors - then all bets are off.

 

You HAVE to retune for the larger turbo. If you don't you are asking for big time problems...