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Rob Thomas' 1997 Cabrio Dyno Results

The dyno has been a useful tool to chart the progress of the performance modifications and to help determine where a certain performance part is working or not working. It can also help to determine a course of action for the next modification.

Unless otherwise stated, all dyno runs were done at Dynospot Racing, in Mountain View, California. First listings are the horse power and torque readings at the wheels. Second rating is the estimated power at the crankshaft (and gain or loss over VWOA's advertised rating) so you can compare it to factory HP/Torque ratings and other publications that advertise crank HP not road HP. Actual dyno printouts can be downloaded or viewed online using the Adobe Acrobat Reader (all dyno plots are in PDF format).

Here are my results by date:

October 19, 2002

113.3 bhp / 121.4 ft-LB torque (130 hp +15 hp / 139.6 ft-LB torque +18.6 ft-LB)
[See Dyno Run...63kb]

I got a used Garrett chip from the VW Vortex Classifieds for $55/shipped to me from the East Coast. Everyone raves about GIAC's programming so I wanted to try it out for myself.

After installing it, it was obvious that it was making a difference, even over my AMS chip from before. The car was significantly quicker overall. It made the AMS chip feel like it was being choked off or being held back. I am guessing GIAC has better fueling maps than other companies.

MidKnight Motorsports AirBox cold air intake
Ractive heatshield filter, with cross-drilled side housing to remain passive
Hartmann Motorsport 70mm "Big-Sound" exhaust system
Hartmann Motorsport bi-kat manifold (dual catalytic converter header)
GIAC chip (optimized for a 260° cam)
Schrick 260° camshaft
AEM Tru-Time adjustable cam gear (set to 4° advance)
ABD Big-Bore Intake (powdercoated black)

There was a peak gain on the dyno...so I am a new Garrett convert! I can't wait to see if an assymetric 260°/268° cam from Bahn Brenner will perform well on a normally aspirated car. I am going to supercharge the Cabrio anyway, but it still would be interesting to see.

May 10, 2002

110.6 bhp / 117.2 ft-LB torque (127.19 hp +12.19 hp / 134.78 ft-LB torque +12.78 ft-LB)
[See Dyno Run...56kb]

At the recommendation of Brandon's to go at least a 2.5" VR6 exhaust, I ordered a system from Hartmann Motorsports in Stuttgart, Germany. 70mm "Big-Sound" system is a 3-muffler system that has 2.8" piping all the way back to the rear muffler. Has a nice look and great quality build.

I got the new header and exhaust installed. It sounds deep and throaty, but not obnoxious or loud. I am really impressed. No apparent loss in low end torque and flows extremely well on the top end. Especially after 4,000rpm. I couldn't wait to get it dyno'ed...

MidKnight Motorsports AirBox cold air intake
Ractive heatshield filter, with cross-drilled side housing to remain passive
Hartmann Motorsport 70mm "Big-Sound" exhaust system
Hartmann Motorsport bi-kat manifold (dual catalytic converter header)
Advanced Motorsports PowerPROM
Schrick 260° camshaft
AEM Tru-Time adjustable cam gear (set to 4° advance)
ABD Big-Bore Intake (powdercoated black)

The peak numbers were dissapointing, but after I overlayed this dyno plot to the one below...I realized that though the peak hp and torque numbers did not increase, the powerband was fattened up throughout the mid-range and top end getting to those numbers. Exactly how it felt by the seat-of-my-pants.

I feel much better about the end result of the bigger exhaust and header install now. I am thinking bigger fuel injectors and a 4-bar fuel pressure regulator should provide even more gains.

March 12, 2001

111.0 bhp / 115.0 ft-LB torque (127.65 hp +12.65 hp / 132.35 ft-LB torque +10.35 ft-LB)
[See Dyno Run...62kb]

It's been killing me to know what the 2 degree advance did as far as real numbers, so I went in at 4:30pm today to get my answers.

MidKnight Motorsports IceBox cold air intake
K&N drop-in filter
Sebring cat-back exhaust system
Advanced Motorsports PowerPROM
Schrick 260° camshaft
AEM Tru-Time adjustable cam gear (set to 2° advance)

On my "butt-dyno" the car feel much more solid throughout the entire rpm band since the cam advance. The car really comes alive in 3rd gear and above. Instead of the power coming in strong above 5,000 rpms after the install, power is more linear and really perks up after 4,250 rpm. Money well spent in my opinion.

March 7, 2001

I just advanced the cam gear 2 degrees and it drastically improved the throttle response! I am assuming I have regained much of the lost torque I had before the cam install, but improved the power throughout the entire rpm range at the same time.

I can't wait to get it dyno-tuned at DSR to get actual numbers!

March 5, 2001

A baseline run was done with the intake, exhaust and VW OEM chip and OEM cam, prior to the installation, to gauge performance of the modified AMS chip and Schrick cam upgrades. This is on the same dyno sheet above for comparison.

102.7 bhp / 120.6 ft-LB torque (118.1 hp +3.1 hp / 138.69 ft-LB torque +16.69 ft-LB)

MidKnight Motorsports Icebox cold air intake
K&N drop-in filter
Sebring cat-back exhaust system
Volkswagen factory (OEM) chip
Volkswagen factory (OEM) camshaft

107.5 bhp / 111.5 ft-LB torque (123.63 hp +8.63 hp / 128.23 ft-LB torque +6.23 ft-LB)
[See Dyno Run...69kb]

MidKnight Motorsports IceBox cold air intake
K&N drop-in filter
Sebring cat-back exhaust system
Advanced Motorsports PowerPROM
Schrick 260° camshaft
AEM Tru-Time adjustable cam gear (set to 0°, no advance yet)

This basically shows me that it made HP (especially above 5,000rpm), but lost a bunch of torque over what I had before. It is going to need to have the cam gear advanced to bring the torque levels up. Stay tuned for the results of that dyno run...hopefully with marked improvements.

September 23, 2000

104.9 bhp / 121.2 ft-LB torque (120.6 hp +5.6 hp / 139.4 ft-LB torque +17.4 ft-LB)
[See Dyno Run...53kb]

MidKnight Motorsports IceBox cold air intake
K&N drop-in filter
Sebring cat-back exhaust system
Advanced Motorsports PowerPROM

VW of America's Advertised Ratings

97.5 bhp* / 103.7 ft-LB torque* (115 hp / 122 ft-LB torque)
* estimated wheel ratings based on 15% loss at crankshaft

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