Assorted Dyno Runs

 

 

The following runs are from an 88 Carrera 3.2 all stock with a cat except with a sport muffler. The dyno is a Dynojet 248h at Dynospot Racing in San Jose. All figures displayed below are rear wheel hp numbers, and must be divided by 0.85 for the corrected crank hp values. The two runs compare the stock chip in red vs. a 911Chips performance chip in blue mated with a premuffler in place of the cat. The chip is programmed for 91 octane California pump gas. Here we see that with our performance chip mated with the exhaust mods, the engine produces a maximum of 211.8 rear wheel hp, or 249 at the flywheel corrected for a 15% loss. Peak hp has extended from the factory peak at 5900 to a new peak at 6200 rpm and 211 rear wheel hp. At 6200 rpm, the car has gained 22 rear wheel hp and 18 ft-lbs of torque, equivalent to 26 hp at the flywheel. You can actually feel the seemingly nonstop hp rise past 6000 rpm to the rev limit. Torque gain has increased an average of 10-12 ft-lbs throughout the mid and upper rpm band.

Compare these power gains to those of other chip 'tuners' as independently performed by Bruce Anderson here, and you will see that our chips produce the most hp under the curve than anyone elses.

 


The following dyno chart represents runs on a 1988 Carrera Club Sport. The car is pristine with about 30k original miles and starts out stock with a catalytic converter, a Borla muffler and cone air filter. The three runs below display the full throttle runs of the car under three stages of modification. Three runs were performed in each configuration, for a total of nine runs. The best of each set are represented below. All runs were performed in fourth gear with the stock Fuchs wheels. All figures displayed below are rear wheel hp numbers, and must be divided by 0.85 for the corrected crank hp values.Dynorun 003 is the lowest curve and was performed with the factory Club Sport chip. The only engine modifications are a Borla muffler and cone air filter. The engine produces a maximum of 200.1 rwhp, or an equivalent of 235.4 engine hp.Dynorun 006 is the middle curve with the only change being the replacement of the factory Club Sport chip with a standard 911Chips performance chip for a premuffler exhaust tuned for 91 octane fuel. Although not programmed specifically for a cat equipped exhaust, nevertheless, an average of 5-8 rwhp has been gained under the power curve from 4500 rpm on. The car produces a maximum of 205.1 rwhp, or an equivalent of 241.3 engine hp.Dynorun 009 is the top most curve with the only change from the previous run being the addition of a Dansk premuffler in combination with the Borla muffler and the same 911Chips performance chip. Note how much smoother the power curves are compared to the stock chip. We can see some additional torque gains around 4000 rpm, along with an extended hp curve past 6000 rpm. Peak hp has extended from 5900 to 6200 rpm with 206.8 hp. At this rpm, total hp has increased from the stock Club Sport chip of 192.2 to 206.8 rwhp, a difference of 14.6 rwhp, or 17 engine hp. The final value is now 206.8 rwhp, or 243 hp corrected to the crank.

Click for larger image

 


 

The following dyno runs are from an '87 Carrera on a DynaPack dyno performed at Eurotech Advanced Automotive in Framingham, MA. The engine and exhaust are completely stock with catalytic converter. Factory rated at 217 hp and dynoing the car with the stock chip, the engine produced a max of 218.7 hp, and 212.2 lb-ft of torque, as shown by the red curves below. Swapping the stock chip with a standard 911Chips performance chip for the stock configuration and 91 octane has increased the peak hp to 233.9 crank hp, and 226.4 ft-lbs of torque, a net gain of 15 hp and 14 ft-lbs of torque as shown by the green power curves below.

 


 

The following runs are from an 85 Carrera street car we dyno tuned and live mapped on a Dynojet 248x. The engine is a stock U.S. motor modified with a set of headers and a Dynomax muffler. The blue lines are with a stock chip; the red lines are with our chip mapped on the dyno for 91 octane. After tuning, the engine produces a peak of 208 rwhp with our performance chip. At 6100 rpm, factoring a 15% drivetrain loss, this engine produces 245 crank hp, a 17 engine hp improvement over the stock chip.

 

 


 

For Porsche club racing, here is a track car we dyno tuned and live mapped on a Dynojet 248c at Game-Face Motorsport in La Habra, California. The engine is a stock U.S. motor except modified with headers and an open exhaust. After tuning the engine produces 216 rwhp. At 6200 rpm, factoring a 15% drivetrain loss, this engine produces 254 hp at the motor.

 

 


 

 

The following runs are from an 88 Carrera POC track car we dyno tuned and live mapped on a Dynojet 424X at GT Pro in Fullerton, California. The engine is a stock U.S. motor modified with a set of European George headers and pair of straight open mufflers. The red lines are with a stock chip with a 6840 rev limit, and the blue lines are with our chip live mapped on the dyno. After tuning, the engine produces a peak of 217 rwhp with our performance chip. At 6200 rpm, factoring a 15% drivetrain loss, this engine produces 256 crank hp, a 18 engine hp improvement over the stock chip along with a much smoother output.

 

 


 

The following runs are from an '88 Carrera on a Superflow SF800 engine dyno at Jerry Woods Enterprises in Campbell, California. The engine is a standard U.S. motor modified with SSI heat exchangers and a Dansk 2 in 1 out sport muffler. The red curves are with the stock chip; the blue curves are with a 911Chips program for the SSI exhaust tuned for 91 octane street gas. At 6000 rpm with the stock chip, the engine produces 213 hp. With our chip, the engine produces 243 hp, a 30 hp improvement over the stock chip.

 


 

 

The following runs are from a 3.2 Carrera we live remapped on a Mustang dyno at Harman Motive in Torrance, CA. The engine is all stock except modified with custom headers and an open exhaust prepared for track racing. Dyno'd with the stock chip, the car delivers a max of 201 hp at the rear wheels (solid curves). After remapping for the engine and race fuel, the car delivers 231 hp at the wheels, a 30 hp gain at the rear wheels (dashed curves), along with a 15-25 ft-lb torque gain throughout the rpm range. Using 15% as a transmission loss factor, engine power is now at 272 hp, with the power gain over the stock chip at 35 hp.

 

 

 

 


 

The following runs are from James Achard's '87 Carrera on a Dynojet 248c. The engine is a stock U.S. motor with the exception of a Midnight Machine Works header race exhaust system. The red lines are with the stock chip, and the blue lines are with a 911Chips program for the headers conservatively tuned for 91 octane street gas. As we can see, the engine produces a peak of 219.4 rwhp with our performance chip. At 6200 rpm, factoring a 15% drivetrain loss, this engine produces 258 crank hp, a 19 crank hp improvement over the stock chip.

 


 

The following run is from an '87 3.2 Carrera we live remapped on a Dynojet 248c at Game-Face Motorsports in La Habra, California. The engine is stock except prepped with headers and a pair of megaphones for track racing. Dyno'd with the stock chip, the car delivers a max of 201 hp at the rear wheels (red curves). Remapping for the engine and race fuel, the car delivers 220.6 hp at the wheels, a 20 hp gain at the rear wheels (blue curves), along with a 15-25 ft-lb torque gain throughout the rpm range. In addition at the peak hp point of 6200 rpm, the engine has gained 27 hp at the wheels. Using 15% as a transmission loss factor, engine power is now at 260 hp, with the power gain over the stock chip at 24 hp.

 

 

 


 

The following run is from a stock U.S. 3.2 motor prepped by Game-Face Motorsport in La Habra, California. The motor is stock with the exception of headers with sport muffler, our larger throttle body, and camshaft to serve as a dual purpose street and track car. Dyno tuned and tested for 91 octane pump gas on a Dynojet 248c, at 6200 rpm, factoring a 15% drivetrain loss, this engine produces 224 HP at the rear wheels, or factoring a 15% transmission loss, produces approximately 264 HP at the engine.

 

 

 


 

The following runs are from an 88 Carrera track car we live mapped on a Dynapack dyno. The engine is a stock U.S. motor modified with a set of mild cams, headers and pair of straight open mufflers. The red lines are with a stock chip with a 6840 rev limit, and the blue lines are with our chip after the live remap. After tuning, the engine produces a peak of 223 rwhp with our performance chip. At 6200 rpm, factoring a 15% drivetrain loss, this engine produces 261 crank hp, a 22 engine hp improvement over the stock chip.

 

 


 

The following are three runs from Chris H's U.S. spec 86 Carrera modified with SSI heat exchangers, twin plug ignition, ExtrudeHoned manifolds, and a 911Chips program matched to the client's mass air flow meter for the configuration. On this dyno, dynorun 002, best of three, produces 214.0 rwhp at 6200 rpm. Factoring a 15% drivetrain loss, this engine produces 252 engine horsepower.

 


 

With various modifications, often times a custom tuned chip from your dyno air/fuel ratio data is the best way to assure maximum power. The following runs are from an '84 3.2 Carrera on a Dynojet 248c. The engine is built with the following: Euro compression pistons, SSI heat exchangers, a dual out sport muffler, ExtrudeHoned intake manifolds, and Webcam camshafts. Originally dynoed with a Weltmeister performance chip, the engine produced 208 hp at the wheels, as shown by the blue curve. While the 208 rwhp is respectable, it is underwhelming for the cost and extent of engine modifications performed. In addition, the driveability was described as lagging and very flat. Examining the air/fuel curve, we can see that the chip is running an air fuel ratio in the mid 11s, much too rich for maximum power. Providing us the dyno air/fuel data, a custom chip was mapped optimizing the air fuel ratios, while revising the part throttle maps for maximum driveability, throttle response, and torque. Programmed for 93 octane fuel, max ignition timing remains relatively unchanged over the Weltmeister. As a result, the car dynoed 223 rwhp, a 15 rwhp gain (18 at the engine) over the Weltmeister chip. Factoring in a 15% drivetrain loss, the engine now produces 262 hp at the crank.

 


 

The following run is from an '89 3.2 Carrera on a Dynojet 248c at Pro Technik in Houston, Texas. The engine is modified with a B&B header exhaust system along with our chip program for the engine combination and 93 octane fuel. The engine produces a peak of 228 rwhp with our performance chip. At 6200 rpm, factoring a 15% drivetrain loss, this engine produces 268 crank hp.

 

 


 

The following chart is from Richard Simpson's European spec '88 Carrera on a Dyno Dynamics machine at Weltmeister's facilities in the U.K. Dyno Dynamics machines display hp corrected to the engine, not wheels. The engine and exhaust are stock. Dynoing the car with the stock chip, the engine produced a max of 223 crank hp, shown by the red power curve below. The stock chip was subsequently replaced with our performance chip for the Euro spec Carrera and 95 European RON octane fuel (equal to ~91 U.S. octane). The resultant redyno produced 240.7 hp at 6100 rpm (shown by the blue curve), a 18 hp gain over the stock chip, with nice average 20 hp and 20 Ft-lb gain in torque throughout the rpm range!

 


 

The following chart is from an European spec '87 Carrera on a Dyno Dynamics machine at Weltmeister's facilities in the U.K. Dynoing the car with the stock chip, the engine produced a max of 223 crank hp at 6000 rpm, shown by the red power curve below. The stock chip was subsequently replaced with our performance chip for the Euro spec Carrera and 98 European RON octane fuel. The resultant redyno produced 244 hp at 6200 rpm (shown by the blue curve), a 21 hp gain over the stock chip, with a 30 hp gain around 6500.

 


 

The following dyno runs are from John Parry's U.S. version '89 Carrera, also on Weltmeister's Dyno Dynamics machine. The engine is stock, with the exception a Euro premuffler in place of the stock catalytic converter. The chip dynoed is the standard 911Chips program for a U.S. specification 3.2 for the sport exhaust/premuffler setup and 91 U.S./95 RON European octane fuel. The results displayed are corrected to engine flywheel HP. Stock Carreras on Weltmeister's dyno often dyno between 220-230 hp on a regular basis with the stock chip, just as the car above. As seen here, with just the replacement of the stock chip with our performance chip, this Carrera produces 247 hp, 24 more hp than Euro 3.2 above using the stock chip, and is actually 3 hp stronger than the same Euro 3.2 after chipping.

 


 

The following dyno runs are from Alan Pole's European spec '88 Clubsport on Weltmeister's Dyno Dynamics machine. The engine is stock with the exception of a NineMeister custom performance chip. As can be seen the engine develops a maximum of 219 hp at the engine at 5900 rpm. The next chart after this is the same 88 Clubsport redynoed with a 911Chips performance chip.

 

The NineMeister performance chip was then swapped with our performance chip in this same '88 Clubsport and remeasured again at Weltmeister's dyno. The resultant horsepower is now 249.7 at 6400 rpm, a nice increase of 30.7 HP.

 


 

The following dyno runs are from Ian Highfield's Euro spec '86 Carrera also on Weltmeister's Dyno Dynamics machine. The engine is stock, with the exception of a sport muffler which was used on both runs. Dynoing the car with the stock chip, the engine produced a max of 239.6 crank hp, shown by the red power curve below. In addition, the air/fuel ratio, or Lambda, shown by the lower red curve indicates the stock chip is excessively rich, acting like a fire extinguisher dampening out the potential combustion energy attainable. A custom chip was then developed for the client from this data, from which the fuel mixtures were corrected to the optimum power point along with program optimization for 98 European RON octane fuel. The resultant redyno produced 255.6 hp, a 16 hp gain over the stock chip.

 


 

For Porsche club racing, the following is a 3.2 track motor and car by AASE Motors in Fullerton, California . The motor is set up running 3.2 U.S. compression pistons and cams, with headers and an open racing exhaust. Live mapped on a Dynojet 242c and programmed to run on race fuel, this motor produces 225 hp at the rear wheels. Factoring in a 15% transmission loss, this motor produces 265 hp at the flywheel. Subsequently, the driver of this car is a frequent top time of the day holder at Porsche club events. Kudos to the work of AASE and the talent of the driver!

 

aase

 


 

The following run is from an '87 3.2 Carrera on a Dynojet 248c. The engine is modified with the following: Euro compression pistons, SSI heat exchangers, GHL muffler, ExtrudeHoned intake manifolds, Webcam 20/21 cams, and ARP bolts. The chip is a custom 911Chips program for the engine combination and 93 octane fuel. The engine produces a peak of 226 rwhp with our performance chip. At 6200 rpm, factoring a 15% drivetrain loss, this engine produces 266 crank hp.

 

 


 

For Porsche club racing here is a 3.2 Carrera track car built and prepped by AASE Motors in Fullerton, California. Built as spec motor with headers and stock cams that live mapped on a Dynojet 248c, with our program custom tuned and programmed for race fuel, the engine produces an outstanding 228 rwhp. Factoring a 15% drivetrain loss, this engine produces 268 engine crank hp. Shortly afterwards, the driver broke and set a new class track record. Congrats!

 

 


 

 

The following run is from an '86 3.2 Carrera live tuned on a Dynojet 424x. For POC racing, the engine is completely stock with the exception of a set of custom stepped racing headers and open exhaust. With our program custom tuned and developed at the dyno for race fuel, the engine produces an outstanding 231 rwhp at 6200 rpm. Factoring a 15% drivetrain loss, this engine produces 274 crank hp.

 

 


 

For POC Porsche club racing, here is a '88 Carrera 3.2 track car built by Vision Motorsports in Laguna Hills, California. The engine, modified with headers and an open exhaust, and dyno tested on Vision's Dynojet, and tuned to run on race fuel, produces an amazing 233.7 hp to the rear wheels, or assuming a 15% transmission loss, is approximately 275 hp at the engine.

 

 


 

The following run is from an '87 3.2 Carrera built by Autometrics Motorsports in Charleston, South Carolina on a Dynojet 248c. The engine modifications include the following: 10.3:1 cr pistons/cylinders, 964 cams, and headers with racing mufflers. The chip is a custom 911Chips program for the engine combination and 93 octane fuel. The engine produces a peak of 234 rwhp with our performance chip. At 6200 rpm, factoring a 15% drivetrain loss, this engine produces 275 crank hp.

 

 


 

The following is from a custom built '84 3.2 by TRE Motorsports on a Dynojet 248c. The combination of the engine build, TRE's race exhaust system, along our chip programmed for the engine package produces 234.7 rwhp at 6500 rpm. Factoring a 15% drivetrain loss, crank hp is 276 hp, a 69 hp improvement over the stock 207 hp motor. Not bad considering the entire intake and fuel injection system remains completely stock and unmodified due to POC class restrictions. Examining the torque curve, not only does it build smoothly to 5000 rpm, but doesn't stop rising until it it peaks out at 6200 rpm! Area under the curve from 4800-7400 rpm is what allows this car to fly. This car outruns track prepped Vipers and E46 M3s at the track as if they were driving Miss Daisy. (Motec? We don't need no stinkin' Motec! :-) )

 


 

The following runs are from an '84 3.2 Carrera on a Dynojet 248c. The engine is modified with the following: Euro compression pistons, racing headers, megaphones, ARP rodbolts, 9K valve springs, a racing valve job with polished ports, and Webcam 20/21 cams. The chip is a custom 911Chips program for the engine combination and 93 octane fuel. The engine produces a peak of 238.8 rwhp with our performance chip. At 6200 rpm, factoring a 15% drivetrain loss, this engine produces 281 crank hp. The following weekend the owner won the PCA time trial class at Willow Springs. Weekend following, he also won his PCA time trial class again at California Speedway, in addition to being 9th overall out of 51 cars, beating at least six 3.6L powered 911s as well as several track prepped and tricked out 944 turbos.

 

 


 

The following is an '89 3.2 to 3.4 liter conversion by Callas Rennsport in Torrance, California. The car, designed as a daily driver to run on 91 octane pump gas, is built with Mahle pistons and cylinders, special camshafts, ARP rod bolts, Extrude Honed manifolds, utilizing the stock exhaust with a our premuffler and a M&K sport muffler. After dyno tuning and live mapping for a new chip for the motor on a Dynojet 248c, at 6200 rpm the motor produces a very nice 228 hp to the rear wheels, along with a peak torque of 204 ft-lbs to the wheels, a nice torque increase of about 30 ft-lbs over a stock 3.2.

 

callas


 

The following is from an '86 3.2 rebuilt to 3.4 liters by TRE Motorsports tuned on a Dynojet 248x. The engine is built with Mahle pistons and cylinders, Webcam camshafts, Extrude Honed intake manifolds, ARP rod bolts, keeping the stock exhaust and muffler along with a sport cat. With a stock chip from an 87 Carrera, the car dynos a max of 207.6 hp, or 244 hp corrected to the engine, as shown by the blue lines in the below chart. With our chip live tuned on the dyno on 91 octane, the engine produces a new max of 232 hp at the wheels, or 273 hp corrected to the engine, a 29 hp gain at 6100 rpm, along with a much smoother power output as shown by the red curves. Examining closely, you can see at 5500 the car has gained 23 hp at the wheels (27hp at the engine) and at 6500 the engine has gained 51 hp at the wheels (60 hp at the engine)!

 

 


 

 

Here is Jeremy Dixon's '87 Carrera which was rebuilt from 3.2 liters to 3.4 liters with a Malhe 3.4l 9.8:1 piston and cylinder conversion set. The engine is modifed with the following: 1 3/4" B&B headers, ExtrudeHoned intake manifolds, FFenSport bored throttle body, 993SS cams, ARP rod bolts, Competition springs and retainers, and a Magnaflow muffler. Along with our custom chip for a 3.4 conversion programmed for 93 octane fuel, the engine produces a peak of 244 hp at the rear wheels.Factoring a 15% drivetrain loss, the engine produces 288 hp at the crank.

 

 


 

Here is Ralph Hollack's '89 Carrera which was rebuilt from 3.2 liters to 3.5 liters with a Mahle piston and cylinder conversion set. The engine is modifed with the following: twin plugs, European George 1 5/8" headers, ExtrudeHoned intake manifolds, FFenSport bored throttle body, Webcam 20/21 cams, mildly ported heads, and a Dansk twin out sport muffler. Along with our custom chip for a 3.5 conversion programmed for 91 octane fuel, the engine produces a peak of 246 hp at the rear wheels on Vision Motorsports' Dynojet 248c. Factoring a 15% drivetrain loss, the engine produces 289 hp at the crank. For more details, read about it in European Car Magazine here, and in the Pelican Parts forum here.


 

 

Here is another 3.2 to 3.5 conversion we tuned for an '88 Carrera on a Dynojet 248c. The engine has been built with Mahle 3.5 pistons and cylinders, along with headers and different camshafts. Dynoed with the stock factory chip, the engine makes a max of 224 rear wheel HP, or 263 HP at the engine factoring a 15% drivetrain loss, shown in the blue curves below. Live mapped on the dyno to optimize the fuel and ignition maps, this engine develops 243 HP at the wheels at 6200 rpm, or 286 HP at the engine, along with a much smoother power curve as shown in the red curve below. Result is a net HP gain of 23 hp at 6200 rpm, along with a broad range gain in torque of about 20 ft-lbs with as much as a 45 ft-lb torque gain at 3500 rpm and 30 hp gains in the 6500+ rpm range.

 

 


 

The following runs are from a completely stock '91 964 on a Dynojet 248c. With the stock chip, the car dynos a max of 219 hp at the wheels (257 hp at the engine) as shown by the red curves in the chart below. With the installation of our chip for 91 octane street fuel, the car dynos a max of 230 hp at the wheels (271 hp at the engine) as shown by the blue curves, a 14 hp gain over the stock chip, along with a 10-14 ft-lb torque gain across the rpm spectrum.

 

 


 

The following runs are from a freshly built 91 964 race car from Kevin Roush of GAS Motorsports in Upland, California. The engine is modified with the following: 3.8L piston/cylinder set, cams, ARP rod bolts, an ultralight flywheel and clutch, and a custom GAS Motorsports 2 in 1 out exhaust with headers. The intake system is stock. With the ultralight flywheel and radical cams, not only did we fix the idle and stalling problem of the stock chip, but did so while retaining an 800 rpm idle. Dynoed with a factory 964RS chip, this engine produced a maximum of 248.6 HP and 225 lbs of torque at the rear wheels on a Dynojet 248c. (red curves) With our custom remap for the engine modifications and 100+ octane race fuel, the engine produces a much smoother output with a max of 277 hp and 249 lbs of torque at the rear wheels, a gain of 29 rear wheel hp, or 34 hp at the engine. (blue curves) If you look closely, at 5000 rpm, the engine has gained 35 rwhp - 41 hp at the crank, and at 6500 rpm, the engine has gained 43 rwhp - 50 hp at the engine! Factoring a 15% drivetrain loss, the engine has gone from producing a max of 292 hp at the crank, to 326 hp at 6000 rpm, exceeding the ouput of the factory 964 RSR race cars.

 

 


 

The following is another modified 964 we custom tuned. The engine has been freshly rebuilt and modifed with 3.8L pistons and cylinders, cams, headers, street mufflers, lightweight flywheel, and some headwork. Dynoed on a Dynojet 248 with the stock chip, the engine produces a max of 250 HP at the wheels, or 294 hp at the engine - red curves below. After custom remapping a new chip from the dyno data for the engine combination and 91 pump fuel, the engine now produces 294 hp at the wheels at 6300 rpm - blue curves below. Factoring a 15% drivetrain loss, this engine produces 323 crank hp, net gain of 29 hp along with a broad based torque gain of 20-25 ft-lbs throughout the rpm range.

 

 


 

The following run is from another 964 race car on a Dynojet 248c built by Planet 9 Eleven in Edmond, OK. The engine has been freshly rebuilt and modifed with 3.6L pistons and cylinders, Pauter rods, headwork, cams, 993 heat exchangers, racing mufflers, and a lightweight flywheel. The chip is a our custom remap for the engine combination and 110 octane race fuel. At 6275 rpm, factoring a 15% drivetrain loss, this engine produces 342 crank hp.

 

cj964dyn

 

 


 

 

The following run is from a 964 race car on a Dynojet 248c built by Autometrics Motorsport in Charleston, S.C. The engine has been freshly rebuilt and modifed with 3.8L pistons and cylinders, cams, headers, racing mufflers, a lightweight flywheel, and a modified intake. The chip is a our custom remap for the engine combination and 100+ octane race fuel. At 6200 rpm, factoring a 15% drivetrain loss, this engine produces 343 crank hp.

 

 


 

The following is a 97 Euro version V-ram 993 measured on a Mustang dyno. The results shown are after installation of our chip which show a max of 280 rear wheel hp at 6500 rpm. Factoring a 15% drivetrain loss, this calculates to 329 hp at the engine. Previously this car had another company's performance chip, which caused the car to run a lean part throttle air fuel ratios, and full throttle upper rpm AFRs were at 11.0:1, much too rich for optimum power. The client was consistenly passed by a 600 hp Camaro at the track. The following weekend after installation of our performance chip, the client won two races, plus, that Camaro was no longer passing his 993 :-).

 

 

 


 

The following dyno chart is a typical fully stock factory 911 3.2L Carrera performed on a Dynojet dynamometer.  The car is an 87 with the factory 28 pin 1267355358 chip, which also came on many of the 88-89 U.S. Carreras.  It was the most aggressive of the series of chips delivered for the Carreras, as they were factory rated at 217 hp.  The dyno results shown below measure and represent rear wheel horsepower.  Factoring a drivetrain loss of 15%, the 186 rwhp works out to 219 flywheel hp. 


 

The following chart represents the same 87 Carrera on the same Dynojet dynamometer subsequent to installing a European premuffler in place of the cat.  The chip has not been changed yet and is still factory.  Now that there is no cat to influence the CO output the afr sensor, we can get a true reading of the air/fuel ratios at full throttle.  We can see that the air fuel ratios are excessively lean throughout the power curve, beginning at around 14.5:1 at 2500 rpm. and dropping to 13.3:1 at 5200 rpm.  The mixture from 5600 rpm on measures rich around 11.6:1, which indicates the factory programmed the mixture above 5500 rpm excessively rich for the catalyzed versions to keep the cat cells cool under sustained full throttle high rpm operation. This may be fine for the cat in Germany on the Autobahn at 150 mph, but robs power for use anywhere else.  As the owner has effectively converted his exhaust to the European configuration by the installation of the premuffler, his flow has increased to the point where fuel optimization is required to maximize his potential.  At full throttle, the Bosch Motronic DME ignores all sensor inputs, including the air flow meter and O2 sensor, and injects a preprogrammed amount of fuel and ignition timing programmed for a stock motor.  Therefore, no matter what modifications you perform to your motor to increase the airflow into it, your DME will still inject the same amount fuel as for a stock motor, and fuel=power. If our afrs become too lean, we start to risk our motor with predetonation. Likewise if the afrs are too rich, we loose power by drowning the motor with excess fuel.  Comparing the two dyno runs, we can see that peak hp at 6000 has increased by an average of 7.5 rwhp, or approximately 8 flywheel hp.  Factoring an assumed 15% drivetrain loss, 193 rwhp works out to 227 flywheel hp, very close the the factory rating of 231 hp for the European version of the Carrera. However note that the power curve between 2000 to 5200 has not changed all that dramatically.  This is because the DME has not been reprogrammed to deliver the additional fuel required as evidenced by the lean afr curve in that region.  The peak numbers have increased only because the factory already preprogrammed the region from 5600 on up excessively rich here for predetonation protection. Here, because of the excessive richness, it is possible to derive additional horsepower by optimizing the mixture,


 

The following dyno chart represents the horsepower and torque attained from George M's' standard 911 '89 3.2 with the exception of the following modifications:  SSIs, Monty single out muffler, and a 911Chips performance chip programmed for SSIs/headers and sport muffler.  Three runs were performed of the same configuration, and again these figures represent rear wheel horsepower.  Factoring in an assumed 15% drivetrain loss, the 208 rwhp works out to 245 flywheel hp. 

 


 

More dyno runs to follow.  Please come back as this site will be updated frequently.