Took the XFire to the dyno shop today .Wanted to establish a baseline prior to doing any mods. We were unable to get it to rev past 4K. Turned off the traction control but it was a no-go. Talked to the tech at the Chrysler dealer and he said it has a sensor that limits rpm if the car does not sense enough load on the drivetrain. Went back to the dyno shop & we tried to dial in some load. He kept turning up the brake until it started to stall the engine but it still would not exceed 4K rpm. So- who's actually had a dyno run done on their car and how did you do it? :?

 

Hmmm this is a problem. If there isn't a way to disable this, then there is no way to dyno the Crossfire. I wonder if one of the aftermarket chips will disable this, or if there is a way to disable it using diagnostic tools. It would be kind of ridiculous if we could never get a dyno of the Crossfire.

 

I was reading a recent issue of scc(sport compact car) and they were comparing europes best(m3, s4, carrera 4s) against evo7's.. they tried to to dyno the m3 and they had a similar problem, but they said the cause was the car's speed sensors are on the front wheels and since the front wheels aren't moving it would engane a early revilimiter.. the crossfire will only rev to 4k in neutral i remember someone saying that, that might be the cause.. i'll try to find the the magazine so i can get more exact explanantion..

later..

 

I'm sure you've dyno'd some SLKs. How do you get it to rev above 4K? Or has something been added to the XFire that prevents it from exceeding 4K rpm unless the car is moving? Would appreciate your expertice on this.

 

I'm pretty sure something has been added to the Crossfire. I haven't heard of this problem in the SLKs. I am going to contact some people today who may have already dynoed the Crossfire, and see what the had to do. I'll let you know if they were able to do it.

 

I have gotten some information on dynoing the Crossfire. Evidently on Mercedes, there is a Dyno mode. It has to be activated using the STAR system at a Mercedes dealer. I am assuming a Crossfire also has this mode. I'm not sure if Crossfire dealers have the STAR system (diagnostic tools), but I assume they do since they need it to work on the Crossfire engine. I would try calling the Crossfire dealer and asking if they can enable the dyno mode for you, or ask for more information on it.

 

yeah i re-read the article, the speedsensor on the m3 is on the front wheels, and when they're not spinning the same speed as the rear wheels, computer only lets it go up to 6500 and cuts off the fun, they even tried disconnecting the speed sensors but that didn't help.. My guess for whp numbers its gonna be around 170whp.. anyone know what slks dyno?

 

Star Diag. may not be required to disable dyno mode, here is how to disable for MB on a 2002 W203 chassis, M211 engine:

http://www.csportcoupe.com/faq.shtml#2

Having not seen a crossfire since the Detroit auto show, I can't offer much more help. Consider this a clue.

Additionally, 2003 coupes with M271 engine use a different procedure.

When it is disabled it returns upon the next start up.