dyno'd my 2002 996 today!!!

Hello all: I dyno'd my car today and was surprised to get 279.5 HP at the wheels. They tell me that 20% is lost between the motor and the wheels( Is that about right, or is the 996 more efficient than that???) If 20% loss of power is true, that would mean the engine is putting out approx. 350 HP (WOW)!!! I find that hard to believe and was expecting 260 HP or so. They could not get an accurate torque reading on the dyno, since the sensor wire wasn't long enough, without getting it wrapped in the wheel. Please enlighten me if I am missing something here. I know Porsche is conservative about "numbers" like this. They never want a vehicle out there putting out less than advertised. Thanks for the info. If I'm right, from what info I have, this is good news. Don't know much about dynos and such. Cheers, DW

Dunno dyno's either. But, are you talking a stock 2002 996 engine putting out 280 HP at the wheels?

20% seems much too high to me. My car was dynoed with 275 hp max at the wheels, and they told me the loss between motor and wheels was 10%.

I think 15-20% is realistic for most cars. I've seen over on the Corvette boards reports of a 15% loss in manual cars and 20% loss with an automatic. Great numbers!

I would have thought that a rear engined car had a lower drivetrain loss than a typical front engine, rear wheel drive car. My mechanic tells me 10-12% drivetrain loss is realistic for a 911. But this is pretty academic because what matters is the hp you get on the wheels.

A couple points... I'm not a dyno expert, but from what I understand there are two types, mass and cyclonic, and they will yield different results. I think that the goal understanding the loss is to accurately estimate a number comparable to the factory spec. Is a 320 hp car actually making 312 or 335? There has been lots of discussion about PAG rating their cars very conservative. This is interesting to me bacause of the X51... how conservative are they? I heard that a guy in Florida dyno'd his X50 TT and got 450 at the rear wheels... 1% loss, I think not. The car simply made more HP than advertised. <img src="graemlins/burnout.gif" border="0" alt="[burnout]" />

Thanks to all who responded. I kind of figured I'd be getting some reponses on this one, since lets face it, talking about rear wheel HP holds interest better than clear side markers and windshield wipers. Palting: You asked about if my 996 was stock. Yes it is, 100%. I was trying to get a decent base to go from in case I "tinker" with it in the future. Thanks again Cheers, DW

Most Corvette owners would tell you about 20 percent for an automatic and about 18 percent for a manual trans. I have heard this for years.

That's the right approach DW-wished I had done a predyno run myself. Which dyno machine was used to measure on your car? Good luck in the mod avenue-there's some good mods to be done on your 3.6-should be some good gains especially from a larger displacement engine. Regards. Mike

996flt6: The dyno software was "dynojet" brand and I believe it is the mass-type of dyno, since I drove up on the roller, tied it down, and "let it RIP". Not to sure about dyno stuff- this was my first dyno. Did your unichip make a big difference?? Contemplating, but not looking forward warranty issues with my dealer, should they develope. I guess when you say I should be able to get decent gains out of the 3.6, the majority of them are out of the unichip, no? Thanks DW

With the Unichip-it's useful if you should add other mods ie exhaust/intakes/cats/headers etc which they can optimize via Unichip. they can just fine tune your car to be better. With my mods so far I'm getting RWHP of 264. My initial run was at 235 bhp so it helped quite abit and the results are noticeable-just better trq thruout the powerband and much smoother running engine. Prior to the chip-I did notice a dip in trq from adding the exhaust but was restored back and then some. The 264 is for 100 octane as well and octane 91 was about 255 but main benefit is better trq at octane 100. First trying at Thunderhill with the octane 100 plus the airetek intake I reached top speed of 120 mph on the straightaway whereas with octane 91 was down to 110 mph so definitely helped. Good luck and enjoy!!! Mike

mike thanks for unichip info DW <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />

For Vipers we use 12-15% (all are manuals) and this has been documented by one person. Are those SAE #'s? Can you post the dyno graph? Good numbers if they are SAE!