(This is cross-posted from the regional forums, but thought the tune results may be of interest to the Tuner/Dyno subforum)

I bit the bug and dropped off my 2007 G35 with the trusted folks at CIN (http://www.cintuning.com/) for a little tuning. First, my relevant mods are:

(1) Stillen airbox + K&N Filture + Stillen Z-tube
(2) Motordyne 5/16" plenum spacer
(3) Motordyne MREV2 lower plenum
(4) Motordyne TDX V2 exhaust

The car initially laid down peak numbers of 269HP/255TQ. Finished peak numbers were 285HP/267TQ, for a net of +16HP / + 13TQ. It's hard to see on the graph (I've attached it in PDF) the before and the after, but the gains are consistent pretty much across the entire powerband and the car feels really woken up, even just driving around town at part-throttle. I asked Ben to send me a data file if he has one - I tried to scan this using our PDF converter at work and it doesn't show up great, and then I managed to spill some liquids on the actual dyno chart later in the day so all hope is lost.

Also, I'd like to say that the customer service at CIN is absolutely fantastic. First, I knew I was planning on putting HFCs on the car at some point so I figured I'd wait until I was done with all the bolt-on mods before I got a tune. CIN/Ben basically just said, we can tune it now, and we'll re-tune it again for free once you get the HFCs.... I think that kind of offer is a pretty rare thing these days. Second, I was trying to figure out a weekend where I could drop the car off since it's kind of hard for me to arrange alternate transportation right now... and Ben let me drop the car off at the shop, drove me down to my office, and then picked me up from my office when the car was done. I mean, you couldn't ask for more from these guys and I wouldn't dare to . All in all was a great experience, and I'm very happy with the car right now (though not as much with my rear tires which, lacking some tread, break loose much too easy) and can't wait to get some more time with it.



The one weird thing that did pop up, is that there is some disconnect between my tach and what RPMs the ECU is seeing - Ben said that all of my runs were to redline, but if you look at the dyno, what should be 7000 rpms is coming up as 6100ish. Has anyone seen that happen before?

 

Was this converted to dynojet numbers? I was on the same rollers at the old location and I got the mustang and converted sae dynojet numbers. I did not have the tach issue when I ran.

 

I don't know if it was or not - it wasn't mentioned to me if it was.

 

First off, thanks for the praise. We think customer satisfaction is the key to maintaining a healthy relationship with our customers.

To answer some questions about your graph and tune, let me explain.

Our dyno is calibrated at an 1.04 correction factor, which is the industry standard. At the bottom of anyones dynojet printouts, it will most likely say the same thing.
We have the newest model Mustang 1100 dyno and software and we re-calibrate it on the first of every month to ensure consistant results.

As to the rpm difference, we read off of the obdII port and the corrilation between that reading and what the tach shows is usually a bit off.
With your car, it was a big difference. It almost makes me think that you have a different rear end gear.

Next time you bring your car in for regular service, I can roughly determine what gear you have without removing it.

 

But if there was a different rear end gear in the car, wouldn't that only like change the wheel speed at any given RPM in any gear? I'm not sure how that would change the RPM output from the ecu.

Mehh, either way I won't lose any sleep over it

 

You are correct! I have been sick the last couple of days and have not been thinking clearly. The tach is controled from the ecu and changing the gear would not effect the signal. I was thinking of the speedometer when I made that comment. It is run off of the transmission.

 

impressive results

 

I have a question. Once you do a uprev tune, what is the highest you can bump the rev limiter on a 5at??? And is it possible to get the car to bounce of the rev limiter instead of having a fuel cutoff?

 

You can put the rev limiter as high as you want, but if you are past the peak of the cars power band, the extra rpm is useless. You want to shift as the engine reaches its peak horsepower so the rpms come down into your torque band.

 

Would you possibly know what most 5at G's put their REV limiter at or is that just all based on your tune with the mods?

Also I recently drove a 5at 2004 G coupe and a 5at 2006 G coupe. From driving both cars really hard I notice that the 2004 G, the car bounced off the rev limiter and while driving the 2006 G, the car didnt bounce of the rev limiter but instead had a fuel cut off. Is there anyway you can remove that and give it that bounce feeling?

The only reason I ask this is bc while having the rev limiter bounce in the 04, it didnt lag in shifting. while the 06 when it hit the rev limiter it did a fuel cutoff and when i shifted it took a while to reengaged and go again.

Im pretty sure its just a safety mechanism to not damage anything.

 

I am not aware of anyway around the fuel cut. I had my rev limiter set to 7100 in my 06 5AT sedan, not because I thought I would make more power but to give me a small buffer to stay off the fuel cut. Most autos I have seen chose 7200.

 

Man that would be awesome to have 7200. But that damn fuel cutoff is annoying compared to REV bouncers the older models have. I like those more than fuel cutoff.

 

fuel cut off is easier on the engine. Bouncing the rev limit causes a whipping action on the timing chain and we all know VQs can develop timing chain rattle.