C200/250CGI tune
You are right, sky is the limit if you have the money, but by the time we spend enough to realise significant gains, well, we could just trade in for a 300 or better.
So I just got word form one of my Benz contacts. The Pistons, Cams and compression ratio are different between the models, as well as the turbo.
He is going to get back to me about specifics, but they definitely run lower compression in the 250's with higher boost pressure.
So basically, short of a substantial rebuild, we are not going to get the same performance out of a 200.
I will get back to you when/if I get my hands on specific details
So I just got word form one of my Benz contacts. The Pistons, Cams and compression ratio are different between the models, as well as the turbo.
He is going to get back to me about specifics, but they definitely run lower compression in the 250's with higher boost pressure.
So basically, short of a substantial rebuild, we are not going to get the same performance out of a 200.
I will get back to you when/if I get my hands on specific details
Wait, how come Edmund's information says it's the same compression as c180/200?
http://www.edmunds.com/mercedes-benz/c-class/2012/road-test-specs1.html
Last edited by Knightmare69; Sep 2, 2014 at 11:33 PM.
Wait, how come Edmund's information says it's the same compression as c180/200?
http://www.edmunds.com/mercedes-benz/c-class/2012/road-test-specs1.html
The C180 is 10.3 (with the 1.6 M271)
I seriously doubt the edmund's, or any other vehicle reviewer, have actually measured the compression ratio in each vehicle. They usually go off of dealer released info. As we all know, Benz is pretty tight lipped about that. Take those figures with a grain of salt...
I am one hundred percent sure that the part numbers differ. Given that the turbo and cam part numbers also differ, it makes sense that the ratio would be different. From a mechanic's perspective, the best way to get more power from an engine with identical bottom ends is to either lower compression and increase boost (cam change required to optimise) or bore it out. They have the same volume (1796cc) so it hasn't been bored.
We will just have to wait and see what comes back form my sources
Last edited by AusMB87; Sep 3, 2014 at 12:54 AM.
The bottom end is almost identical. conrods, block and crank are the same. Pistons aren't
The Best of Mercedes & AMG
Tuning was done on a dyno (dynojet).
Overall results were -
Before(With Rado IC and DP): 175PS, 278Nm
After (With Rado IC, DP, and Unichip): 195PS, 306Nm
Keep in mind these are taken at the wheel and not on the crank / flywheel. I can post the dyno sheet if anyone is interested. Looking forward to more updates from you guys as well!
As for the tune - there are many benefits to going with something from brabus, carlsson etc. Much more comprehensive units.
Above all, why do what's already been done? The figuring it out is more fun to me than bolting it on. The day I run out of mods is probably the day the car goes up for sale :-)



