Ok I brought this up way back when I 1st joined and bought the crossfire and entered in my personal hell. But that's neither here or there.

THIS is the only car forum where I have yet to find dyno numbers. Its all guessing, if someone has posted there rwhp from a legitimate dyno, I apologize. But come on guys even the 626 forum has posted whp from dyno runs. Even the focus forum does lol. Even though a great deal of those focii can beat our cars, still funny none the less. And please don't bring up that lame dyno sheet showing SAE hp gains from one of those chip companies or claims from a company. I believe I here lord nikon speaking of doing rolling road runs. But I don't recall any being posted. SO dyno runs stock and modded alike are welcome. Thanks for the time.

 

I am getting two dyno runs tomorrow morning. Baseline run with just K&N filters and second run with Borla exhaust installed. I'll post what I find. Don't you have a machine near you? Its not that expensive to do it. And I have a question...if I post the info, do I get Senior Member Status on this Forum? Just kidding.

Chris

 

Yah, I got a machine near me. And with just spending over a grand on a winter tire and wheel set, don't want to pay $100 for 2 runs at the local wheel everytime i mod something. Call me cheap i guess. Rather take that $100 and put it towards an upsolute chip. With my other cars i used others peoples dynos and then dynoed mine after I used what i learned. Works quite nicely that way.

Thanks for the much need info, I'd give you senior status for that. Since your the 1st I believe to post numbers. This will be interesting. Im guessing around 175-180 whp with the k&n's and around 185 ish with the exhaust.

 

That's what I'm hoping for, too.

Chris

 

I was just informed by the shop that the Crossfire can't be dyno tested as there is a speed sensor in the front that works with the ECU to compare speed between the front and rear wheels. At 4,500 RPM the car shuts down as there is no wheel speed in the front while the rears are turning. No data available. There are a few lessons here...the first is beware the claims of the speed and horsepower equipment manufacturers, with no dyno information...how good are their claims? Secondly, ask around and test, test, test in your own car. Share what you find. Still glad to be driving a Crossfire.

Chris

 

There's an article in the November Car and Driver that describes how to disable this speed sensors in Mercedes cars for "diagnostic purposes." I'll have to see if I can dig that up.

 

Just have to pull the relay, but you will also lose function of your ABS.

 

I don't think you need ABS on a dyno test !

 

Here are two graphs.

First one is stock Crossfire before and after Powerchip software.

Second one is stock normally aspirated 3.2L vs. stock C32 AMG, which shares the engine with SRT6. This 330 HP business is simply marketing, it makes 349 HP. I looked at SRT6 and I do not see anything different from AMG motors, except for plastic engine cover.

 

If this is correct, what it shows is that the standard Xfire 3.2 is putting out considerably less than the rated 215 h.p. and even the chipped version is less than the rated 215 h.p.

Is that what were saying here.

 

The dyno is measuring horsepower to rear wheels. The marketing is advertising horsepower at the crankshaft. The difference is the power loss through the drivetrain. The measured numbers are pretty close to what Bullseye guessed.

 

My understanding is that all the manufacturers these days rate the engines horsepower as 'net' horsepower; in other words at the rear wheels. The days where 'gross' horsepower was rated ended back in the 1970's.

 

Perhaps I'm wrong, but I have a different understanding of 'net' horsepower and 'gross' horsepower. My understanding is that 'gross' horsepower is power at the crankshaft without all the engine accessories (alternator, power steering pump, etc.). 'Net' horsepower is power at the crankshaft with all the engine accessories. 'Wheel' horsepower (wph) is horsepower at the rear wheels.

 

MBtuner: Great info. on the dyno numbers. 9 hp to the wheels with the power chip and 13 ft-lbs torque! Great! Just to confirm, the stock 3.2 in our Xfires does't need any internal mods to supercharge to 330+ hp? This is what Kleemans also said. Seems too good to be true but I am becoming a believer. Do you know how they got by the relay/sensor for the dyno? If it is just a disconnect, how did you identify the right one? Thanks

 

You are correct and I admit that I was partially wrong. I have researched this and found the following from an automotive web page explaining Torque and Horsepower; I now understand the reason for much lower horsepower readings on the charts:


"There are many different ways of measuring the power of an engine. Brake horsepower is a common term and refers to the power measured at the crankshaft using a "prony" brake. A prony brake was a simple lever that was connected to the crankshaft with a brake. As the brake was applied, the lever would deflect and power was indicated. Nowadays, computers and strain gauges are used to measure the power.

Rear wheel horsepower is just what it implies - horsepower applied by the rear wheels. A chassis dynamometer is used to measure the power transferred by the drive wheels onto the dynamometer's rollers. Brake horsepower is much lower than the horsepower specs provided by the manufacturers, because of all the power used by the transmission, final drive, and accessories.

Gross horsepower is the power measured at the crankshaft without any engine accessories. This includes removing the air cleaner and ductwork, exhaust system, water pump drive, and any other devices driven by the engine. Prior to 1973, horsepower specifications were listed by the manufacturers as gross horsepower. After 1972, manufacturers provided net horsepower specifications.

Net horsepower is also measured at the crankshaft before it goes into the transmission, but this time the engine is operated as it is installed in the vehicle, complete with accessories and ductwork."

 

I thought you had to change compression meaning valves and pistons. Is this right ?
And lower end bearings.

 

Dan:
According to Kleemanns Technical Manager Cory Umemoto, the supercharger goes on the "stock" 3.2 block with zero internal mods. He said that they have done a number of superchargers on the motors in the SLK with "NO" power train issues. As we know it is the same engine and train as ours. The power is 330 hp plus a ECU chip which costs $1,000 and adds 20 hp and 300 rpm. If you send me a personal e-mail; I will forward the correspondence that I had with him.
With just the supercharger, 330hp plus the chip 350hp, so if you do any work on the short block, or heads who knows? He did say that our power train can handle 400 ft-lbs continuous torque without modifications and the Super Charger and chip is around 345 ft-lbs torque ><.

 

MBtuner,

In the first dyno output you posted, do you know whether this if for Powerchip's "Gold 91" or "Gold 93"?

 

I checked out Powerchip’s site. Powerchip claims a 9% increase in net horsepower at the crankshaft (21 hp gain). Mbtuner’s dyno output shows a 5% increase in horsepower at the rear wheels (9 hp gain). That is an interesting discrepancy. Nevertheless, I am interested in their product.

I have a few questions about the impact of Powerchip’s product on the car manufacturer’s warranty.

Powerchip claims that the car manufacturer’s warranty is not affected by their chip flash. To support this, they quote a couple of lines from a position statement by the Specialty Equipment Market Association (this statement is SEMA’s opinion and not a legal document).

Has anyone on this forum ever had a warranty denied due to an after market chip flash? Has anyone ever been in a dispute with a dealer over a warranty due to an after market chip flash? Has anyone actually received anything in writing, in advance, from a dealer regarding after market chip flashes and the impact on the car’s warranty?

 

AlvinByars: Here is copy of the information from Powerchip directly, which may answer your question.
"The Powerchip is designed in unison with the factory engine management system, and will comply with any emission test in the same way as a standard vehicle. Furthermore, the Powerchip enhanced vehicle will continue to utilise the various diagnostic scan capabilities as per factory specification, which means that the dealership or factory cannot tell that you have made any changes to the software. All items offered by Powerchip are warranted to be free from defects in workmanship and quality prior to installation. This warranty does not cover abuse, misuse, labor, faulty installation, failure of related or unrelated parts."
If this is true, mums the word!