It sure feels better to add a wild guess 120 HP, but it's wrong in my opinion.

Well, AMS does. They claim that 800 HP crank number, no?


What exactly is the difference between two otherwise identical cars, one makes 420 HP and the other one 800 HP on the same dyno when you look at the only interesting point in time when you want to measure the losses:

That's at the end of the pull when you have no more gear engaged and no connection between drivetrain and engine. You could have a million HP, the drivetrain wouldn't know. There is just no force to it other than the internal losses.

Andreas

 

Read the article on friction. It will make sense then.

 

What bar was that at and fuel were you on? The AMS guys claim 1.7 bar which doesn't seem to be realistic. Doesn't the ECU shut down the TB at 1.4bar? How many people run 1.7 bar??

It sure would be nice if people would advertise realistic numbers on pump gas as that is how 99% of people run these cars. Lot of tuners claim huge hp claims for one time 1/4 mile or 60-130 numbers but how would that set up perform when hammered continuously for 30 min at the track? I suspect not so well based on what I've seen. I've run my lowly 550 Rturbo (that's crank according to RUF) at the track against a number of claimed high hp cars including a Evoms 700 car and pulled them on the straight fairly easily which leads me to believe there is quite a bit of exaggeration by a lot of tuners as real world performance is quite a bit less. My car on the long straight at our track was just ever so slightly quicker than a 2011 ZR1 and was dead even with an MP4c both of which are advertised as a tick over 600hp stock. It seems that manufacturers are pretty "real" or even a bit on the low side with their power numbers unlike the aftermarket crowd. I would take most of the tuner huge hp claims with a large grain of salt as real world repeatable performance just is not there for the most part. Big numbers sell however so I get it as a marketing tool.

 

PWDERHOUND, are your turbos k24/18's?

 

How do you explain the fact that on our Dyno Dynamics 4WD Dyno we have run several late model cars (m5, C63 AMG) and they are within a couple of HP of what the factory quote.

 

What's to explain? We aren't talking about absolutes here. HP is not a unit that is controlled by the Division of Weights and Measures. A manufacturer may advertise a car as having 500 HP. Maybe it is, maybe it isn't. Most likely it is at least 500 HP. If they sell 5,000 copies of this car do you think every single one has exactly 500.00000 HP? More than likely 500 is the bottom end of what they expect, or for some sort of organizational purposes it is advertised at 500.

 

Why are you so angry?

If you would answer some of my questions I had for you regarding what dyno you went to, trap speeds of your car, weight of your car, etc. then maybe we could get somewhere. You gave no information at all.

You just seem to be hell bent on attacking us and saying we're liars.

1. You're saying we're manipulating and deceiving everyone because we're rating crank HP based on a 15% loss. Then the whole car industry is a sham, because that is the average what people use for a manual gearbox car, and it's roughly what we've seen on the dyno on stock cars comparing rated HP to whp. Is it always 15%? no, sometime it can be 10%, sometimes more depending many things, what tires are on the car, the fluid used in the drivetrain, etc.

2. Manipulation? We say capable of 800hp. if we meant wheel horsepower we would write 800 wheel horsepower. How are we manipulating or deceiving. So our products should be rated at what an average person using who knows what components and tuning combination? That would be insane. That's like a speaker company having speakers capable of handling 1000watts RMS max power but only advertising 750 watts because most people won't have amps strong enough to drive them. You see my point?

Almost all our products are rated at crank horsepower, just like most other companies do and how OEM's rate their stuff. When we do testing and show dyno results showing whp gains, we clearly state that. If you have proof of deceit please show me. Watch TV, car manufactures showing cars jumping, doing ridiculous stunts that are faked, food advertised that looks like nothing even close to what you get when you actually order, etc. THAT is fake and technically manipulating advertising.

Here let me show you.
http://www.911tuning.com/996-Turbo/F...rade-p-52.html
850 crank horsepower capable with 635 cc/min injectors is the claim. Using a 15% drivetrain loss which you claim is outlandish, that comes out to 722whp on these injectors, or much more whp if you say the drivetrain loss is less. Go ahead, try to make 722whp or more on 635cc/min injectors, let's see how that works out. To give you an idea a stock GTR has 560cc/min injectors and they max out at 550whp on our dyno.
You seem to be the champion of 911 tuning and how happy you are with them and insist I'm being manipulative and deceitful. I'm curious if you will respond about this fuel system claim.

3. I don't know what A28's you are referring to. The GT28 based turbo's we are using are capable of more than 900hp. So let me ask you this, what are A28's good for crank HP? Let's first nail that down. Next, I'll buy you a first class plane ticket to Chicago, Pay you for your time off work, put you up in nice hotel, buy you dinner with limo service, and give you $10,000 cash if I cant' make that on our Alpha 9 997.1tt A28 based turbo setup on our car. You can look all over the car as much as you want and be there the entire time for the dyno process etc. If you're so confident in your beliefs then please take me up on my offer, it would be silly for you not to, downright stupid. In fact can everyone here including you, agree that if you don't take me on this offer everything you are saying and doing here is libel on your part?

As far as the Jap tuner vs German tuner. Really? You think Borg Warner and Garrett/Honeywell have turbo engineers that only deal with 'Jap' cars, and they have other engineers that are only experts with 'German' car applications. If you understand the concept of engine performance and how all the components work together it doesn't matter if you're working with a Model T ford or Bugatti Veyron.

Again my offer stands, please accept it.

-Martin

 

I did not call his exhaust garbage. I called the catalytic converter he uses in the exhaust garbage. I'm calling a spade a spade. Do you think a $60 muffler shop cat belongs on a high performance Porsche exhaust? The quality, fit and finish of the exhaust is nice. Everything is actually nice quality except for the crappy cat's and the louvered baffle design in the mufflers. That's something that isn't apparent as a less than ideal performance part unless you have backpressure measurements to compare louvered cores' to perforated cores.

-Martin

 

We've been around for 13 years, have 30 employees and are growing every year, I don't intend on going anywhere but up. I agree this business is volatile, because most people don't know what they're doing or base their business on selling parts cheap without the service or knowledge to back it up.

 

Sorry I'm having a little bit of trouble understanding you. You say 520 clutch hp, which is a loss of 20hp, can you elaborate on that?

The only way to really know would be to put it on a engine dyno, then that same engine in a chassis dyno. Engine dyno take out all the following losses; Driveshaft & CV joints, all the gears in the gearbox, ring and pinion in the diff, the, the losses from the tires, all the losses from fluid shear, all the bearing drag in the diff, trans, hubs, etc. Gears have an efficiency rating. That means that they have X amount of loss. That efficiency rating doesn't change because you are putting less or more power through the gear.
Accelerating all the mass of the components -gear, shafts, diff, axels, brake rotors, wheels/tries also consume HP. The HP it takes to acclerate the mass won't change much based on HP, but losses due to mechanical efficiencies of gears, bearing drag, etc will.

-Martin

 

I believe manufacturer's hp rating is the minimum guaranteed. I think that is industry standard. RUF, for example, told me on the 550 Rturbo , 550 is the guaranteed minimum crank hp on 93 octane taking into consideration the output variances between engines. Most engines will obviously be above that number. This approach seems to be the exact opposite of most tuners which will quote the highest hp number for the strongest engine, on the best day, at the highest boost, on the highest octane, when the stars are in alignment, etc..

 

Agreed.

 

No, they are RUF K24 hybrids that I have been told are K24/26 variants. They spool pretty quick for a k24. I'm at full boost (1.3 bar) by 3500rpm.

 

You find both figures on my chart. The dyno has measured both. This is no guess.

The car is breaking the heavy roll of dyno, so there also is friction in play. I understand what you would like to say with the friction argument, but given that the measured drivetrain loss of my car was only 20 HP while breaking the drum of the dyno, let's me think that the plain guessed figure of 15% without any backup or validation is too high.

Power to the wheel is what counts and your 680ish is already very high for this turbo. 1.7 bar and this small turbo is a stretch in my book. IATs and timing would be interesting to see.

Andreas

 

Mark, Markskis exhaust is kick ***. I had it on my a28 setup. It is
fantastic quality and it sounds great.

On the setup that I have now I wouldn't use it. When you get to the
crazy horsepower level you wanna go straight pipes.

But for 99% of sane people with a Porsche, it is a world class exhaust
system and a real bargain for the money!