Cobb AccessPort for 370Z!

blackbird

Has anyone had any problems with Cobb Accessports and engine code for ECU not working correctly? Has anyone done any Cam tuning with the Cobb? If anyone has, please PM me I have some other info but this is too public.

westpak

there is no cam tuning yet

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semtex

Here's Denny's dyno sheet.

__________________
"There are no small accidents on this circuit." -- Ayrton Senna
316.8whp & 248 ft/lbs (Dyno Dynamics) | 319whp & 256 ft/lbs (DynoJet) (04/23/10)
Stillen G3 CAI, CBE, Pulley / F.I. LTH / GTSpec Ladder Brace / Setrab Oil Cooler / UpRev-tuned by Forged Perf.

Denny McLain

Semtex

I thank you sir.

Note this is SAE and not standard so the power is probably 5-6 hp less than what most people post. Regardless, low in my opinion. Bone stock with 300 miles on it the car made 275.4 (SAE) and with just a Y-pipe and Berk cat made 288.9. IF the two dyno's read the same, the car only picked up 15 hp from Gen III intake, Headers, full exhaust and tuning.

As mentioned.........I'm completely stumped and ready to punt. Step 1 is to call Cobb so I can get the programmer and tuning program working. Step 2 is a revisit to my origional dyno.

Denny McLain

I've been to Cobb in Plano TX three or four times. In the beginning they used my car to read the ECU to get data so they could develop the softare. Every time I visit, get the impression they are completely standup and unlike most companies, do not overhype gains.

Most people whom tune do not give out secrets but after you've got the knack of doing a couple, it's not as much rocket science as you would think. Calvin whom works the dyno and does the tuning, was very knowledgeable and competent. He was very straight forward saying he didn't know why the car didn't more power and asked that I take it back to the original dyno for comparison.

Think it's more of an issue of everything being so new, there are gremlins to find and bugs to work out. Evidently the computers are very complicated and my gut says it's a matter of time. If not, there might be a new Grand Sport or Z06 Corvette on my X-mas list.

semtex

It just so happens that this is the reason UpRev gives for taking so long on development of their software for the 370. And VVEL adds an additional layer of complexity, apparently.

__________________
"There are no small accidents on this circuit." -- Ayrton Senna
316.8whp & 248 ft/lbs (Dyno Dynamics) | 319whp & 256 ft/lbs (DynoJet) (04/23/10)
Stillen G3 CAI, CBE, Pulley / F.I. LTH / GTSpec Ladder Brace / Setrab Oil Cooler / UpRev-tuned by Forged Perf.

westpak

Was yours on a Mustang dyno? If not and it was on a Dynojet you need to add about 10% to the Mustang dyno numbers to get similar Dynojet numbers.

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semtex

Wait . . . they didn't do a fresh baseline run on the Mustang prior to tuning? Like both runs 1 and 2 in this graph are post-tune?

__________________
"There are no small accidents on this circuit." -- Ayrton Senna
316.8whp & 248 ft/lbs (Dyno Dynamics) | 319whp & 256 ft/lbs (DynoJet) (04/23/10)
Stillen G3 CAI, CBE, Pulley / F.I. LTH / GTSpec Ladder Brace / Setrab Oil Cooler / UpRev-tuned by Forged Perf.

Denny McLain

Depends upon the software. Because the Mustang always reads lower than a Dynojet and people want big numbers, they tweaked the later software to read closer.

Another confusing part is Cobb had a dyno sheet for a stock 370Z that made 289 rwhp. That's 14 hp more than what my Dynojet stock baseline was.

"Confused like a big dog" is the key statemdent so many things don't add up. The power output really should have changed with the air/fuel ratio. The only thing I can do is get the software up and running and give it another swing at bat.

Denny McLain

More confusion. If you look at the time the runs were made #2 was first and #1 was five hours of tuning later. The session started about 10:00am and it took a good 30 minutes to get the initial read. The run @10:40 was the baseline.

Kinky thing is the car improved on the low end where the air/fuel was close and did nothing on top where the most improvements were made. So...where is that dog again?

Denny McLain

There is a lot of conjecture that can be made here. If you look closely at the dyno sheet there are slight changes around 4500 rpm, 7100 rpm and 7700 rpm. When I saw those, the first thing I did was check the fuel/air and then ask Calvin if the car was pulling out timing at those points. He said the timing was good and his feeling was the car was changing cam timing at those points and a lot more could be had when the VVEL software is perfected. You would see a puff of smoke every time it hit the 7100-7200 mark, so something was going on.

Also..... while I'm making blind guesses, might as well make a few more. Notice the slight improvements in the 2000 to 4500 range where Calvin thought the first VVEL table was. It did for sure improve slightly in that range. Is it tuning software, or does the car learn one VVEL table at a time? Will it pick up on top later?

The rev limit was set from 7500 to 8000 rpm and as you can see, it takes a sharp drop just past 7500 rpm. Is that because it needs to learn from never being there? Or, did the engineers pull back on cam timing to keep people from over revving the engine??

Is the tac accurate? I now see it hit 8200 and doesn't hit the limiter. Or, is the new rev limit not accurate?

Inquiring minds want to know.

RCZ

Some interesting questions. One thing I remember regarding the RPM limit and the chart. If Im not mistaken, the shelf technosquare flash also ups the rev limit, but their hp curve climbed all the way to redline at 8100 or so. Then again, I don't believe anything that comes out of that shop, so it could have been bs too. Maybe it needs to learn, maybe it needs to be taught what to do after 7500. Perhaps The upper VVEL table is only programed for 7500 RPM where it tops out and becomes inefficient there after?

Can't wait to get some answers for the vvel tables, seems like there's some hidden power/response to be squeezed out by optimizing the timing. There's a really good chance that Nissan left that on the not so aggressive side in order to comply with emission regs...

Denny McLain

Every performance car manufacturer is infamous for sandbagging. Look at the new Nismo. All of a sudden the redline is 7900 rpm and the car makes 350hp from a better exhaust. Will that be standard for all 2010 350Z sport models? What about 2011? There is more in the engine and it's in the computer. I seriously doubt they will do a redo on the engine for the next 4-5 years, just computer/bolt on tweaks.

Denny McLain

Has anyone actually gotten the Accessport to hook up to their computer?

I've not tried to connect it to the car as it was just tuned, but I can't get the updater to work. Hence, no drivers etc. Just sent another request for the tuning software as my prior had expired and the links they direct to do not work.

Still that confused big dog. Their service disclaimer basically says to not call but go to their website. That was a lot of help.

semtex

You might want to try sending a PM to Sharif to see if he has any advice. Sharif wanted to do mine with Cobb, but I decided to hold off and wait to see what UpRev releases. Anyway, Sharif (Forged Performance) is a Cobb Pro-Tuner and might be able to help.

__________________
"There are no small accidents on this circuit." -- Ayrton Senna
316.8whp & 248 ft/lbs (Dyno Dynamics) | 319whp & 256 ft/lbs (DynoJet) (04/23/10)
Stillen G3 CAI, CBE, Pulley / F.I. LTH / GTSpec Ladder Brace / Setrab Oil Cooler / UpRev-tuned by Forged Perf.