Cobb AccessPort for 370Z!

Denny McLain

Travis

I appreciate your response.

Frankly liked everyone at the Cobb Plano facility and all seemed to be stand-up regular people. A third party within the industry with a vested interest in Cobb doing well hooked me up with you guys thinking it may be a good marriage. (At one time I worked directly with the engineers at Haltech to developed an engine management system for LTx F-bodies. Currently have money invested in developing some other new 370Z products.)

On at least two occasions prior I e-mailed back dyno findings with attached logs on issues found with the program directly to you and copied both Neil and Calvin. No one seemed to give a fat rat on feedback and never heard boo back. So much for the marriage as I couldn't even get a hello kiss.


FYI.......The 370Z front 02 sensors are wideband according to a number of sources.. As mentioned, literally threw away all my logs but from memory the AccessPort 02 readouts were all over the place below 4000 rpm and showed about a half a point rich over 4000 as compared to RPM's dyno wideband.


Pig rich is a 20% reduction in fuel economy for no real reason showing A/F readings in the 12's during hwy cruising. Under perfect conditions, it takes about 14.6 lbs of air to completely burn 1 lb of fuel (an air/fuel ratio of 14.6:1) Most factory driving fuel maps are below but very close to that magic number under normal operating temperatures and loads. Although 14.6 A/F is the perfect ratio chemically, not every oxygen molecule in the air will "find" a fuel molecule to react (burn) with.

During my last trip to see if the software was working better, the car was getting 23 mpg at a steady 70mph. Pulled into a gas station, removed the tuning putting the stock program back in and it jumped immediately to a steady 27 mph.

How can that be mechanical?? Nice try, no cigar!

Your correct on full throttle A/R readings, however as a general rule WOT A/F can vary greatly depending upon the individual car. I've seen optimum N/A performance in the mid 12's and also seen mid 13's work the best for certain cars. fyi.....Pro Stock tunes for low 14's. Forced induction in the high 11's to low/mid 12's. Agreed, these cars seem to like mid to mid high 12's. The WOT reading are fine. No issues. Driving A/F's are always higher.



Cobb website and download your latest software and made sure my firmware was current. So as to prevent prior issues, I transferred the primary fuel A/F and other settings such as rev limit manually making it a complete fresh reflash. The MAF tables were not touched by either myself or Calvin at Plano. Nada, Zippo. Stock to stock to stock MAF.

It did the exact same thing with the latest of latest everything from a fresh start.



As mentioned prior, these were e-mailed directly to you hoping to not only resolve issues for myself, but anyone else using it. I paid for the dyno time out of my pocket and offered everything free.


Again, found in the past altering MAF calibrations can be a real pain and a lot of driving/dyno time to get everything correct. If I were to play with the MAF settings, it would be because issues are obvious or trying to find that extra 1-2 hp. Generally not worth the effort if it ain't broken.


At one time thinking bigger was always better, used to always either purchase a larger or have the existing MAF bodies ported only to find out I was taking a step backwards. The advent of wideband 02's and data logging changed that.

Yes, air input can adversely affect tuning and A/F. However, I've not experienced anything drastic enough to warrant the type of issues I'm seeing from simple air intakes. Again, nice try, no cigar.


COBB Tuning[/QUOTE]
We are more than happy to take another look at your car and we would like to get you back on the road with the car behaving to your satisfaction. You are always welcome to bring your car by our Plano facility if you are having issues with your tune. Barring that, if you can supply us with datalogs or graphs from your other tuning sessions, we can be of more service to making your car perform up to your standards.

Travis
COBB Tuning[/QUOTE]


Thanks for the offer but I'm washing my hands entirely. Really would rather have that refund...Please!