TaTommyWS6

WOW, I'm glad I got such a definitive answer about this! <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

I think I'm going to just get LS1Edit and experiment and learn. I may wind up getting a different rear in the future after this one blows up, so at least then I could change my ratio on the computer myself.

Also, I will probably add headers after the cam is installed, as time and money allows...

I see there is still plenty of controversy about what's best, and from what I'm reading, even if money WASN'T an issue, there still is no agreed upon answer to my not so simple question!

Thanks again, and I'll start reading up on the correct was to tune these cars...

Tommy <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Team ZR-1

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Predator:
<strong> JR, it's interesting that a-tap's DELTORQ is "bogus," which forces the user to seek out a wideband for any kind of decent tune (unless you tune by O2s only, which is unreliable at best). I suspect that this intentional, and indirectly throws business to dyno operators and some tuners. I smell a conspiracy here. <img border="0" alt="[evil]" title="" src="graemlins/gr_devil.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Well whatever their reason is it is a bummer for those using atap for the PCM is a built in dyno.

I showed B&B 2 years ago that they had a math bug for DelTq, they agreed and then they just ignored fixing it.
Interesting people will buy that $150 toy that sits on the dash and gives out performance numbers but refuse to use the built in Deltq of the PCM.
Delivered torque in PCM is close enough to use as a indicator to know if a tuning change was good or bad and this allows then the car to be driven on straight level roads or pulling up a hill to see how powertrain performs overall at different load factors.

Tim Sloper

John,

How do you ensure a safe A/F ratio on a FI car with the method you described? You keep implying a WB isn't necessary to tune but you don't indicate how you know whether or not you are running the car at a safe A/F ratio.

Tim

Team ZR-1

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by JNorris:
<strong> Team ZR-1

John what scan tool do you recommend?

Thanks

John </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">John,
I tested autotap, efilive and Ease for months for each.
The Ease Personal GM enhanced OBD-II scanner wins hands down. It always connects, never drops connections, their scaling is correct since they are a Tier 2 supply to GM and are used by some states for smog testing so it is a solid scanner that after doing well over 2,000 PCM recording is consistant and I trust what it reports.
It does work on all microsoft OS'es, even XP, it supports USB and DB-9 serial ports.

You can scan without recording or do both at the same time, its meters screen will average functions for you so like LTFTs, knock, timing, etc, no need to export to a spreadsheet.

If your really into this tuning or a shop the Pro version can read all body and chassie functions and will do bi directional for some engine functions like injectors, idle RPMs, reset fuel trims, turn fans on/off.

Team ZR-1

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Tim Sloper:
<strong> John,

How do you ensure a safe A/F ratio on a FI car with the method you described? You keep implying a WB isn't necessary to tune but you don't indicate how you know whether or not you are running the car at a safe A/F ratio.

Tim </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Poor or good AFR would be seen via knock or misfire counts, in hi or low octane timing tables, what the MAF and MAP values are so there is lots of parameters to use as a guidestick, up and beyond just the AFR though the STFTs tell me how close the AFR is to performance. Using Deltq PID tells me if I went a bit too lean or not.

Via PCM recordings I have designed a 12 page spreadsheet program and once raw data is imported to it I go through all 23 trim cells and several compares of engine functions and can pretty well tell by the trim cells via what MAP, MAF, IAT, RPM and engine load if AFR was too lean or not.
If PE timing of around 28 degrees and no knock then attempting to get more timing gets no more performance and can even reduce torque so in short tuning is more important on the type of scanner being used, longer time at 100 % engine load and lots of time having done ECM and PCM tuning to know how one function effects another.

Tim Sloper

Do you use a WB for WOT tuning? Everything you have presented seems to be geared towards closed loop tuning in which you have little control over A/F anyways so anything you do would be moving the LTrims not the A/F ratio at partial throttle once the LTrims have adjusted. Timing you would have full control over.

At WOT none of what you stated applies. This is where a WB is crucial as DelTQ, STFTs, etc. will not tell you what the A/F ratio is. Take a dry nitrous setup for example on a new H/C combo... how in the world would you determine if you are running 12:1 or 13.5:1 on the spray? Knock retard doesn't necessarily mean things are too lean. Zero knock retard doesn't necessarily mean that the A/F ratio is safe. If I'm going to tune a combo that someone has spent major $ on I'm going to make sure I know where everything is at before that customers walks out the door. It just makes no sense to me that someone would rely on such indirect data when you can measure the information directly (A/F ratio) very easily and accurately.

Tim

Team ZR-1

Very interesting your posts continue to say only way to get a overall performance tune is by use of a dyno and 1 wideband O2 but I just visited your website and you charge $450 when the PCM only is shipped for tuning.
That means with zero PCM and engine parameter history the customer is paying for a tuning method you claim does not work, esp if you think those PCM functions/sensors are meaningless/indirect.

If ONE O2 stuck in ONE muffler tip was valid, then why do not carmakers install them there, it would be much cheaper all around for them and easy for car owners to replace, stick their hand into a muffler tip and bingo replaced.

Any commom sense knows reading 1 muffler tip after the cat has done its job, the hugh difference of cooler exhuast and the outside air in muffler tip makes,
plus the inbalance from B1 to B2 says its not worth the extra $125 for using one on a dyno where the drum is 100's of lbs lighter then the car/fluids/driver is produces less realworld values then the ones you claim in the PCM are useless.

If you believe the only performance factor is what AFR is, well I suggest you read what a PCM really does, what the ROM program in PCM does and that EPA and carmakers are all stupid for even they say at WOT, being richer, rather then too lean has no ill effect and clearly if the engine was too lean knock and timing would show that instantly, so what you think are indirect, well hate to tell you but know matter what you do with a wideband or where you stick it, the PCM's program in ROM will do whatever it wants and drift the AFR anywhere within the +/- 22-25% threshold within 1 hour of engine time of any changes made due to what was seen in a muffler tip. Being an engine 99% of the time are in part throttle ( according to EPA) doing a tune solely on dyno conditons will result in a tune that excludes what happens in 19 other trim cells.

A simple leak in the exhaust will totally fake out the O2s, including a wideband that generally is dirty sitting in a muffler tip and rarely calibrated.
Being the car is hundreds of lbs greater then the drum, then dyno is assuming ( from WB O2 view) that AFR is richer when in fact the additional weight requires more fuel to move that mass but the dyno is assuming the mass equals the drums weight thus claims too rich.

Wideband is bogus since it assumes AFR is richer but in fact engine going into PE was too lean, causing PCM to increase injector pulse width, and thus what was seen as rich was in fact PCM attempting to bring fuel trims back closer to zero.
If you think STFTs are indirect values, good luck, for engine functions solely from what it reports.

Wideband is solely a marketing tool to induce people to paying 150 to $300 more for a tune, if that is true then doing mail order of PCM ONLY tuning sounds counteracting the pitch of a wideband/dyno only process using autotap, IMHO, the worst scanner on the market.

Closed loop tuning only ?
so are you saying PE and WOT are in open loop or are you saying all the functions I mentioned are only used in closed loop ?


</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Tim Sloper:
<strong> Do you use a WB for WOT tuning? Everything you have presented seems to be geared towards closed loop tuning in which you have little control over A/F anyways so anything you do would be moving the LTrims not the A/F ratio at partial throttle once the LTrims have adjusted. Timing you would have full control over.

At WOT none of what you stated applies. This is where a WB is crucial as DelTQ, STFTs, etc. will not tell you what the A/F ratio is. Take a dry nitrous setup for example on a new H/C combo... how in the world would you determine if you are running 12:1 or 13.5:1 on the spray? Knock retard doesn't necessarily mean things are too lean. Zero knock retard doesn't necessarily mean that the A/F ratio is safe. If I'm going to tune a combo that someone has spent major $ on I'm going to make sure I know where everything is at before that customers walks out the door. It just makes no sense to me that someone would rely on such indirect data when you can measure the information directly (A/F ratio) very easily and accurately.

Tim </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">

Tim Sloper

John,

We do offer mail order tuning. I do not make any claims that the first attempt will be 100% accurate. Without realtime feedback it is a best estimate type scenario. I don't think anyone would ever expect it to be as efficient a process as dyno/street tuning. Regardless... we will stand behind our work and correct what needs to be corrected. I've used mail order tuning for my personal car in the past and it took a few interations. It took some data collecting on my end as the customer but it did work and the car ran very well. Also, don't confuse my method of tuning with your method of tuning. Not all sensors/PCM values are important at all times... you seem to have trouble making the distiction as to when they are useful and for what they are useful.

Why do you keep using the O2 in the muffler tip scenario? We do not place the WB O2 in the muffler tip. If possible the WB O2 sensor is placed in a secondary O2 position. If that is not an option the O2 is placed in one of the primary O2 positions (harmless when using our method of tuning). Our preferred method of PE tuning is to bias the LTrims to the negative side. This is harmless and ensures that the LTrims will never deviate from 0 when in PE mode. This then allows us to dial in the A/F ratio and know that 50 miles later that A/F ratio will remain exactly where we put it. As for B1 vs B2 we will use the leaner bank as our reference. The beauty of the WB is that we know what the A/F ratio is across the RPM range. I would imagine the extra $125 WB/dyno expense was worth it to a recent customer who brought in his ATI C5 and left knowing his A/F ratio was safe, his KR was gone, and his C5 had ~30 more RWHP than when he brough it in.

You need to stop mixing up the words I use. I never claimed STFTs to be indirect values. STFTs are locked to 0 during PE mode by the PCM thus have no useful meaning during PE mode. This is a fact. Again... my issue with your method primarily resides with WOT tuning which you have yet to address in a direct clear fashion.

Do you or do you not use a WB to aid in PE mode tuning? If not, why would you be against running a portable WB O2 sensor on the street? If you had to tune a speed density scenario your entire method of tuning would go right out the window... you would have absolutely no choice but to use a wideband O2 sensor.

I was involved with the Incon TT development and we always used a portable WB unit when tuning the prototype car on the street. It was worth its weight in gold. I even used it when I was using mail order to tune my personal car. You would be suprised how useful WB data can be.

Tim

JNorris

iTrader: (4)

Team ZR-1

John what scan tool do you recommend?

Thanks

John