Horsepower differences 2002/2003/2004?

I have seen different horsepower ratings for the 2002 vs 2003/2004 model years. The 2002 rates at 320hp and the 2003/2004 315hp? What is the deal with this?

YOU WILL NEVER FEEL THE DIFFRENCE, UNLESS ITS A 50TH ANIVER OR A TURBO/GT3 THE 3.6S ARE THE SAME

The PET catalog lists the power ratings in kw. I don't know how accurate the PET catalogue is, but the listings are as follows: '02 3.6L = 232kw = 315.53 DIN hp = 311.12 SAE hp. '03-'04 3.6L = 235kw = 319.51 DIN hp = 315.14 SAE hp. Also interesting are the 3.4L listings: '98-'00 3.4L = 220kw = 299.12 DIN hp = 295.02 SAE hp. '01 3.4L = 221kw = 300.48 DIN hp = 296.37 SAE hp. I think perhaps some publications publish SAE numbers, others, DIN numbers. Some publications actually tell you which conversion from kw they are using.

From 02 to 04 all the base carreras had the same power... 320hp... in 05 (997) they went up to 325hp..

The Mechanical Engineer is correct. In the US, all Porsche sales materials and manuals specified the HP at 320 for 02', 03' and 04'. In other markets such as the UK, the ratings were different. Although the rating was increased 5 HP for the 05' 997, the engine longblock from throttle body to exhaust manifold is the same as the 996'. The only differences were in accessory routing, the airbox, the exhaust plumping and revised ECU.

This is correct. The engine and HP ratings of the '02, '03, and '04 models are the same.

But is it 320 or 315 offically? A lot of magazines online like car and driver say 315. I say 320 because its more, but I wonder what the official number is. One theory I had was the euro models are 320, and the U.S. models are 315 because of our crappy gas.

My '04 Porsche ownwers manual spec says 320 HP, which is the same for '02 & '03.

I can't explain why some magazines show 315 hp, but Porsche officially states 320 hp for the the US model.

I don't think the owner's manual is a reliable source for HP ratings. They tend to round them.

The 40th anniversary has the X51 kit which produces 345 hp, as will any other C2 or C4 with the X51 kit.

2002 911 320Bhp 2003 2004 315Bhp

What does the X51 kit consist of, and I am assuming that you could have only gotten it on the 3.6's?

Intake manifolds, larger cast aluminum and intake pipes CNC ported heads, Cams (higher lift for intake, diferent timing) Exhaust headers Oil pan baffles New map for the DME Third radiator

Intake cams only. Exhaust cams are just re-indexed. I question the oil pan baffles. I researched this with my local dealer and in the parts catalog both the pan and the baffle are showing the same for both the X51 and the regular 3.6l. It comes with a completely different ECU, they don't just reprogram the old one.

I have the 04' US dealer brochure and it is correctly listed as 320 hp, not 315 hp.

Wow, that is a lot of crap. It sounds like it would be 10k to upgrade, might as well go with a Supercharger for that. How much was it from the factory?

Vehicle Type: 911 Carrera (996) / 911 Carrera 4 (996) / 911 Carrera 4S (996), 911 Targa (996) Model Year: As of �02 (2) Concerns: Performance increase to 254 kW (345 HP) Engine Type: Standard engine M96/03 � 235 kW (320 HP) Equipment: Only for vehicles with manual transmission. General: A parts set ��Carrera Powerkit�� is available to retrofit the standard engine with an increased performance of 254 kW (345 HP). The following parts in the engine are replaced, exchanged or modified to achieve this increased performance: � new intake manifold with modified cross-section (material: sand cast aluminium ); � new intake pipe supports adapted to the form of the intake manifold; � new exhaust manifolds with larger cross-section and optimized flow behavior; � new cylinder heads with optimized, CNC-milled inlet ducts; � new camshafts with larger valve stroke on the inlet side and modified inlet and outlet timing; � inlet valve springs adapted to the enlarged valve stroke; � modified partition box in the oil pan; � modified maps for the DME control module. The following steps are also taken on the vehicle: � new underside panel in the transmission area; � additional radiator in connection with modified front spoiler, except on the 911 Carrera 4S (996). The higher-performance engine is also available as an option when ordering a new vehicles � 911 Carrera / 911 Carrera 4 / 911 Carrera 4S / 911 Targa � under Exclusive Option X51. Software: In August 2002, the software for the PST2 was updated to version 14.0. After completing the programming of the DME control module, the control module is given a new part number for the respective country or variant (see also Point 8). The new number can be read out under the menu item �Identification�. Engine Break-in: Engine speeds greater than 5,000 rpm are not permitted over a run of 300 miles (500 km). The maximum engine output of 254 kW (345 HP) depends on the total mileage of the engine at the time of the retrofit and is achieved as from a total mileage of approx. 6,000 miles (10,000 km). Warranty Info.: New vehicle with increased performance of Option X51: New-vehicle warranty in accordance with the Porsche Guidelines. Retrofitting: Warranty in accordance with the Repair Conditions and the Warranty Conditions for Original Porsche Parts. If the engine to be converted has over 24,000 miles (40,000 km), the crankshaft main bearings and the connecting-rod bearings must also be replaced. If there is obvious wear on the connecting-rod bushings (scores), the connecting rods must also be replaced. Technical Information 911 (996) 7/02 1 1001 Option X51 � Increased Engine Performance �2002 Porsche Cars North America, Inc. Service Date: 12-6-02 Page 1 of 13 Binder - Group 1, Part 1, Engine � Technical Info: Standard engines �Carrera Powerkit� engines Engine type: M96/03 M96/03 S Number of cylinders: 6 6 Bore: 96 mm 96 mm Stroke: 82.8 mm 82.8 mm Displacement: 3,596 cm3 3,596 cm3 Compression ratio: 11.3 : 1 11.3 : 1 Max. engine power of 235 kW (320 HP) 254 kW (345 HP) at engine speed: 6,800 rpm 6,800 rpm Max. torque: 370 Nm (274 ftlb.) 370 Nm (274 ftlb.) Max. litre output: 65.4 kW/l (89 HP/l) 70.6 kW/l (96 HP/l) Rpm limitation at: 7,300 rpm 7,300 rpm Idling speed: 670 � 40 rpm 670 � 40 rpm Top speed: 285 km/h (178 mph) 290 km/h (181 mph) 280 km/h (175 mph) for 285 km/h (178 mph) for 911 Carrera 4S 911 Carrera 4S Information: Please inform your sales staff and customers with regard to the engine break-in instructions. Copy the first two pages of this Technical Information bulletin and give these to the customer! 911 (996) Technical Information 7/02 1 1001 �2002 Porsche Cars North America, Inc. Date: 12-6-02 Service Page 2 of 13 � Parts Information: 000.044.100.12 Performance increase to 254 kW (345 HP); Set 000.044.100.13 Sealing set 000.044.100.14* Additional radiator; Set * Do not order for 911 Carrera 4S (996)! Parts List: 000.044.100.12 � Set; performance increase: 996.104.043.41 1 x Cylinder head set; cylinders 1-3 and 4-6; incl. valves, valve springs, plugs and cylinder head cover (incl. plugs) 999.217.155.09 23 x Hexagon-head bolt EN 1665�M6 x 30 micro-encapsulated (cyl. head cover) 996.105.061.40 1 x Set of camshafts, consisting of 2 x inlet camshafts for cylinders or optionally /061.41 1-3/4-6 and 2 x exhaust camshafts for cylinders 1-3/4-6 996.105.203.00 2 x Diamond ring (behind camshaft adjuster on inlet camshaft) 996.105.254.00 2 x Lock screw, adjuster on camshaft 900.378.242.09 8 x Hexagon-head bolt M6 x 12 (chain sprocket on camshaft) 999.217.150.09 8 x Hexagon-head bolt EN1665�M6 x 20 micro-encapsulated 996.107.243.40 1 x Assembly: oil pan with partition box 900.378.035.09 13 x Hexagon-head bolt M6 x 16 � EN1665 � (oil pan to engine) 996.110.980.40 2 x Intake distributor 996.110.983.00 2 x Intake pipe support 900.378.172.09 12 x Hexagon-head bolt DIN 6921�M6 x 35; intake distributor to support 996.110.170.51 1 x Sucking jet pump 996.111.101.40 1 x Exhaust manifold; cylinders 1-3 996.111.102.40 1 x Exhaust manifold; cylinders 4-6 999.075.071.00 12 x Hexagon-head bolt M8 x 28; DIN EN 24017; manifold flange 900.075.459.09 1 x Screw M6 x 12; DIN EN 24017 999.218.005.02 2 x Pan-head screw M6 x 16; DIN 912; Hall sender 996.573.980.00 1 x Suction line; air-conditioning compressor 996.113.239.40 1 x Secondary air line 996.110.511.50 1 x Angle 999.511.118.02 1 x Retaining clamp 996.110.151.01 1 x Adapter for sucking jet pump 999.230.498.40 1 x Pipe connection AD 15 (90) 999.919.130.09 5 x Hexagon-head bolt DIN 6921�M6 x 35 996.504.029.00 1 x Underside panel, transmission area 996.110.221.58 1 x Rubber sleeve from air cleaner to throttle adjuster with additional connection for sucking jet pump Technical Information 911 (996) 7/02 1 1001 �2002 Porsche Cars North America, Inc. Service Date: 12-6-02 Page 3 of 13 � Parts List: (cont�d) 000.044.100.14 � Additional radiator set: 996.106.037.51 1 x Radiator 900.378.074.09 4 x Hexagon-head bolt M8 x 16; DIN 6921 930.113.430.00 4 x Rubber mount 999.591.869.02 4 x Sheetmetal nut M8 900.378.036.09 2 x Hexagon-head bolt M6 x 12; DIN 9221 999.507.550.02 2 x Sheetmetal nut M6 999.512.552.00 2 x Spring band clamp 28 x 12 996.504.487.02 1 x Upper retaining bracket 996.504.485.02 1 x Lower retaining bracket 996.106.666.52 1 x Hose 996.106.665.55 1 x Hose 996.505.561.02.01C 1 x Front end inner frame 996.575.141.02 1 x Front end air duct 000.044.100.13 � Sealing set: 996.110.103.50 2 x Seal; intake pipe/cylinder head 996.110.247.50 6 x Seal; intake pipe/intake distributor 996.111.107.55 2 x Seal; exhaust manifold 996.104.201.02 2 x Head gasket 999.707.404.40 1 x O-ring 17.05 x 1.78; Hall sender 900.123.007.30 1 x Sealing washer A14 x 18 for oil pressure sensor 996.104.203.00 6 x Sealing washer for spark plug 996.104.215.54 4 x Side cap for camshaft (green) 996.104.216.02 2 x Side cap for camshaft (brown) 996.105.244.03 4 x Cover 000.043.203.73 1 x Sealant, 30 ml 999.707.344.40 3 x O-ring 18.77 x 1.78; chain tensioner 999.701.163.40 2 x O-ring 11.0 x 2.5; sucking jet pump 996.107.221.51 2 x O-ring 95 x 2.5; oil extraction pump 999.707.346.40 6 x O-ring 15.0 x 3.0; guide piece screw 900.123.147.30 3 x Sealing ring A27 x 32; chain tensioner 944.110.901.01 12 x O-ring 7.52 x 3.53; injection valve 999.707.277.40 1 x O-ring 20.0 x 2.5; pressure regulator 999.707.276.40 1 x O-ring 5.0 x 2.5; pressure regulator 900.123.106.30 1 x Sealing ring A18 x 24; plug (oil drain plug) 999.701.761.40 6 x O-ring 28.0 x 2.0; sealing washer for cup housing / cyl. head The sealing set contains only those seals required for conversion of the engine (replacing cylinder heads, intake and exhaust manifolds).

its about 20k if i remember right + labor figure another 3k or so

Disclaimer: I have no experience with the 3.6L X51. My responses are based on my experience and the TSB. Really? Because the kit includes new exhaust cams. The kit for the 3.4L includes a new pan, and the baffles are much different. Can't answer for the 3.6. The TSB does not list a new ECU and includes instructions to reflash it with the new map.

Oh, I'd trust the brochure.

Could someone tell me what the torque figures are for each year (99-2004)? Did they jump up in 2002 when they went to the 3.6L? Thanks.

Torque for 3.4L = 258 ft-lbs. 3.6L = 273 ft-lbs.

The exhaust cams for the regular 3.6l and X51 are exactly the same. If you look at the part list above, there are 2 different cam kits listed. Keep in mind that it is a fresh engine, you may want to reuse your exhaust cams when they get installed in the new heads. With more miles, you would want to replace them due to wear. Hence why they list the intake cams as a standard kit and the intake cams + the exhaust cams as an optional kit. There is a runout procedure in the service manual to check if they can be reused. There is a different degreeing procedure for how both cams are installed versus a regular 3.6. You will also notice they don't list an exhaust only cam kit above for this reason. Porsche has been packaging an ECU in the kit to swap out the original for the DME upgrade. I didn't ask what they did with the original. The part number listed above for the 'X51 Oil Pan', 996.107.243.40, is not a valid part number in either Porsche's North American part number system or the part number system out of Germany. The only place you will find this number is at Suncoast. If you have your dealer pull the 3.6l pan and baffle, the picture Suncoast shows looks exactly the same as a regular 3.6l pan (I had Boardwalk Porsche do this for me). I am still trying to figure this one out, but best guess is the pan was a change made for crank clearance with the longer stroke crank in the 3.6 over the 3.4. The cheapest price I have seen the kit go for is $7500 through Fabspeed. Porsche specifies installation to be 25 hours of labor. Here is a link to one of the dealers who carries it and what they charge for installation. http://porsche.parkplacestores.com/capo.html 99-01 3.4l: 258 @ 4600 rpms 02-04 3.6l: 273 @ 4250 rpms 3.6l X51: 273 @ 4800 rpms When they upped the displacement and added variocam plus, they not only increased the torque output; it now peaks lower in the rpm band. The X51 makes the same peak torque, just at higher rpms. With the X51, the give up some low end power to make more high end power. Although the 997' is rated 5 hp higher than the 996', it has the same torque peak at the same rpms: 273 @ 4250 rpms.

Hah hah hah, you guys crack me up.....I enjoy this way too much and it is quite informative on a micro basis. BUT, after all this time; WHAT'S up with the supercharger thingy.....They blow more 996 engines than a **** star does football teams! UNLESS the engine is disassembled and reconfigured properly. better to trade up!

Do you have proof of this somewhere? I have heard basically nothing but good about S/C's from all on this Forum.

Proof...Dude....I've have a few scatter in just the last year. They (owner) were not the sharpest tool in the shed to buy them that way to begin with. IF you don't go to the track, there's less problems BUT if you run them hard on the track....well...have a nice day is not in the cards. Mark hARd the beat the "narzi's" at that game.