Nixcision

iTrader: (3)

*sigh* was hoping for something legitimate -ish here... looks like VR tune round 2 so far

infin8ti

From what I see, peak hp gained about 6hp.

The other thing to note is that the midrange improved from 4500-5500rpm. At 5000rpm, it gained ~20hp.

The graph looks a lot better overall.

Too bad it doesn't give 15+ throughout the entire range.

NVMarkus

iTrader: (2)

Alas, super disappointed in this, I really dont like when a company tells you that you will see 16-20 hp to the wheels change for their product and then someone not affiliated with it, comes out with this....
I guess the but dyno told them it was 16-20, as I am sure that if feels faster with the midrange improvement...
Thank you for doing this!!! I hope that you didnt pay full price for this...

skyshadow

On the bright side, there is a clear change being made to the AFR of the vehicle. That change is not being corrected by the ECU either. Remember, My tuner stated that the "stock map" on the piggy back could use A LOT of work to tweek it into giving more power accross the board. He also stated that without the ability of spark control, no "piggy back" system will be able to give you much power. The system is tunable, So i will have him see what he can do.
You will get follow up dyno pulls for all this but unfortunately there will be other performance parts installed as well. I have too many things piling up in my garage (new intake filter, headers, lighter wheels).
As for how long it takes for the ECU to correct, it used to be said that it was 100 miles. But, now that I have tested at over 200 miles people are claiming 1000. In future pulls, I can still determine if the ECU has corrected by the AFR.

scott1256c

I noticed the improvement in the curve as well. Even without the top end HP increase, that midrange improvement is worth noting.
I also noticed the better AFR. That was measured with a sensor up the tailpipe? How accurate are those? With that improvement in AFR, I would have thought you'd see better than a 6HP improvement. Still disappointed.

Thanks for going to the trouble and expense of testing it. I appreciate it and I'm sure the community in general appreciates it also.

metaleckz

iTrader: (9)

Even the same pump! LOL

skyshadow

^ Bro, when testing for a forum you have to take every precation. This guys will say the craziest things to prove or disprove something. I attempted to have as controlled enviroment as my budget could afford.

skyshadow

Yeah, it was a sensor about 3ft into the tailpipe. You know, I honestly dont know how accurate they are. good question. I will say, whatever their accuracy, it was the same sensor in the same pipe at the same distance for "before" and "after". The change is real.
Also, he builds some pretty big power vehicles with that method so it has to be somewhat accurate.

WylieKylie

iTrader: (2)

Can the dyno shop overlay the old runs with the new runs?

Claiming failure because of a measly 6hp gain at ~6500rpm, while ignoring what could be a sizeable gain in area under the curve in the midrange (where the engine spends most of its time anyway) is pretty shortsighted. But it is pretty hard to understand (and even harder to explain) the difference in area under the curve without overlaid plots, so 6hp gain internet math will rule the discussion.

redspencer

iTrader: (1)

For an easier comparison, attached is a quick snapshot of what looked to be the best powerbands from the before-and-after dynos.

scott1256c

Assuming you shift exactly at 6700, the rpm in the next gear is
gear ratio ... rpm
1 ... 3.52 ... 3883
2 ... 2.04 ... 4598
3 ... 1.40 ... 4786
4 ... 1.00 ... 4824
5 ... 0.72 ... 5490
6 ... 0.59

5 and 6 are not important for heavy throttle acceleration, but for the other 4 gears, the "optimal" shift rpm match is in the interesting part of that 2nd vs 1st graph.

First to 2nd starts a little lower, but from 4600 or so up to about 6000 there is improvement in torque, and every gear has to go through that region, provided you're maxing throttle and shifting high. Don't know how much that would improve 1/4 mi. times. Couldn't hurt though.

LexSense

iTrader: (2)

Provided that IF you can squeeze more power out with a tune and have it actually stick, then this might not be too bad of an investment.

Again the if it sticks part is biggest factor.

Thanks for the hard work and time you've put in @ skyshadow.
Please keep us updated on any further tuning and long term adaptations.

skyshadow

^That brings up a good question. How far down the road should I do a new pull to confirm if the AFR alteration is not being corrected? Like I stated before, my power numbers will be different with the new parts but the AFR should still reflect the same, right? You guys really wanting a 1000 mile test or was that sarcasm?

Gville350

iTrader: (10)

I think after 1000+ miles will confirm the longevity of the unit's tune sticking with the car and not being overrun by the factory ECM. Wish a wideband could be placed in a more legitimate location upstream so that the A/Fs are more accurate.

But seriously, thanks for all your work on this. I'm sure more will stand-up and post their experiences with the unit here soon.

LexSense

iTrader: (2)

I'd say at least 800 miles, as my experience with VR Tuned this is where power seems to fade.