Fitting the exhaust produced 205hp and 241 lb/ft. This is an average increase over the chip of 2.5hp and 3.6 lb/ft across the rev range. Looking at these averages you could suggest the exhaust contributes little but it actually provides good gains from 2000-4000rpm, and again boosts power over 5500rpm. However, Jeff did indicate he's seen an extra 10 lb/ft on the 2.0T with a more expensive HJS cat from the UK. Unfortunately these cost twice as much at the Techtonics downpipe.
Fitting the Evo CAI we got 206hp and 248 lb/ft. Looking at the averages, we gained 4hp and 4.6 lb/ft over the chip and exhaust. Alternatively, we now have an average of 31.8hp and 39.3 lb/ft over stock. Again, the first figures don't appear significant but remember these are averages. In many places the gains are bigger, especially from 2700-4000, where torque really climbs. However, both the intake and exhaust suffer from the same fuel delivery problems the software encountered. So we're hoping there's a tuner working on an uprated fuel pump, injectors and software as we speak...
| | Power (hp@rpm) | Torque (lb/ft@rpm) |
| Stock | 177.72 @ 6200 | 190.12 @ 3200 |
| GIAC software | 201.22 @ 5600 | 230.18 @ 3400 |
| GIAC + TT exhaust | 205.50 @ 5600 | 241.47 @ 3300 |
| GIAC + TT + Evoms CAI | 206.25 @ 6000 | 247.97 @ 3300 |
On The Street
When the car returned from the dyno the increase was instantly noticeable. This was partly because the exhaust and intake sound sportier, but also because we'd gained 30hp and 60 lb/ft - a very useful increase.
It makes overtaking a breeze, and accelerating to speed entering the freeway takes seconds. It's increased our safety margins, if you like. It's also made the car more entertaining to drive and we've seen an improvement in gas mileage thanks to greater efficiency - it's only a few mpg but it'll add up over the next year.
Shortly after the test we removed the intake at the request of Evoms. They wanted to conduct their own tests. Despite its minimal contribution on paper we felt a reduction in throttle response and a loss of mid-range torque. The car was also more sedate - we missed the sucking and whooshing it contributed. Jeff Moss is confident the production intake will give more power thanks to smoother bends, suggesting the sharp bend in the neck of the pre-production version was probably causing our woes.
With the intake gone, we found that the exhaust is only subtly louder than stock. It has a deeper note but certainly doesn't attract unwanted attention - the body kit and 20s do that!
We should also confirm that the software performs flawlessly. There's not a flat spot or hesitation anywhere in the rev range. It pulls cleanly through the gears, even from very low rpm in traffic. And it possesses phenomenal torque for daily driving in the sweet spot from about 3000-4500rpm.
At the end of the day, we're very happy with the results but are looking for more power, so stay tuned. We've recently tested two other combinations of chip, exhaust and intake, and will bring you the results in the next two issues.