Power & Torque Curves 
The peak power gained by the Link was 117kw at 5000rpm. The tractive effort peaked at around 3350N just after 4000rpm. It is important to note here that the above power output resulted in my car detonating during the acceleration tests (eg. under full load acceleration).  

I went back to DMA for a second tune and the car was re-tuned on the rolling road by doing a few laps of the block. In order to capture the new power curve, I took the car it to APS for another dyno. The power figure had now dropped to 102kw with a tractive effort of 2950N. 

The two maps compared. 

Danny was not present when the second dyno was run and consequently challenged the results after seeing them (believing they were too low). In order to try and settle the debate, I arranged a meeting with him to re-fit the Link (it had since been removed). The intention was to re-dyno the car with the same parameters as recorded on the second tune to check if the dyno results were correct or not. Despite several emails and phone calls confirming the meeting, Danny did not show up for the refit nor return my calls afterwards. 

For the record, I do not believe the dyno results were fudged. Probably the biggest factor confirming this were the acceleration tests Patrick Felstead and I ran. They were performed before the second dyno was run and we had no expectations. The tests independently showed the power to be quite down on the first tune and I have no hesitation in publishing the second dyno as I believe it to be correct. 

Parameter Snapshot 

The parameters used in the re-tune. Note the change in AF ratios above 3500 to stop the car pinging.  

Fuel Economy 
A total of 1331km were covered with the Link. The initial fuel consumption was just over 10L/km. A result that is most likely effected by the lean AFR. After the re-tune, consumption increased to 12.6L/km. 

Acceleration Times 
Recording acceleration times was difficult the first time due to the pinging we encountered. We pulled out of the first run after we hit 100km/hr. We decided to have a second go and persisted through the 400m mark despite the severe pinging. The G-tech recorded a time of 6.20sec and 14.22sec at 155.4km/hr for the 0-100km/hr and 400m respectively. 

The times we recorded were alarming in that they were not only slower than expected, but slower than the standard car. As the launches were quite consistent and no worse than previous runs, we initially thought there was a problem with the G-Tech. A check of the data recorded by our own accelerometer showed the time was accurate however. The answer as to why the car produced such a slow time can be found in the dyno curve. The Link offers less power than the standard car below 3500rpm. Quite a bit less in fact (some 20 odd kw). This is felt on the road and also during the acceleration runs. With two people and a full tank of fuel, the car struggled to get going from a standing start with the reduced power down low. Similarly, higher in the rev range the detonation would have effected the acceleration, negating any (graphed) power gains.  

After the re-tune, we again went out to Carrum to record some more acceleration data. In three runs, we could only average 6.28secs for the 100 and 14.61secs at 156.9km/hr for the 400m. Once again, marginally slower than the car in standard form. Our figures were later confirmed by the second dyno run. The power was unchanged below 3500rpm (eg. less than standard) and was now also lower above 5500rpm. 

Cold Start Operation 
I have to be brutally honest here but the cold start operation was simply awful. The car would consistently stall at least once at start up and the idle was all over the place whilst the engine warmed up. Danny did improve this after the re-tune. I discussed the problem with a few Link tuners and was told the cold start was an area that was difficult to get right.  

Customer Service 
I found Danny to be quite friendly and easy to talk to. Unfortunately during the course of this article, he lost some staff which reduced his flexibility in meeting with me to tune the car. This may have also explained the problems I had in trying to arrange a third meeting with him to verify the second dyno tune on the Link.  

Driveability 
The first thing I noticed with the Link was that the car felt sluggish at low rpm. As explained above, this is due to the fact the power and torque are significantly less than the standard WRX under about 3500rpm. A look at the parameters shows why. The max boost at 3000rpm is only 8psi. Well under the standard cars 13psi. This boost then climbs over the next 500rpm to almost 17psi. This sudden jump means it's a case of either power on or power off depending on which side of the 3500rpm border you drive.  

I should note that Danny originally wanted to install a 3 port solenoid for better control and increased boost (a standard fitting with the Link for MY99s). I declined due to the fact that big power wasn't the goal here but overall driveability was. I had also stated that I did not want to risk engine damage by running high boost in an effort for more power. 

I felt the part throttle response of the Link was a bit jerky. Lightly adjusting the throttle (at any speed) would cause the car to lurch (similar to an auto "hunting" gears) and really started to annoy me after a while. Discussions with other Link tuners (in NSW and the UK) revealed this was characteristic of the Link. I was told the Link is hard to tune when it comes to getting good driveability. Strangely enough, the jerkiness did improve after a week although was still noticeable (or maybe I just got used to it ?). 

On the plus side, put the foot down and it’s a different story. Although, the car feels slow to start initially, it really bolts into action after 3500rpm (as the dyno indicates). The power is remarkably smooth and the car pulls strongly all the way to redline. The Link gets most of its power gains by upping the boost on the car to a peak (which will vary depending on temp) of just under 18psi. This drops back to 15-16psi at higher revs. Most of this power is under full throttle and there is not the same kick under part throttle. In fact, the part throttle response feels the same as per the standard car. To be fair, the car does feel faster than the acceleration times indicate.