I got the Stage 2 chip upgrade from speedtuning and my EGR has been thwarted and I can say the car is not a muscle car but is better. Total cost is $410.

I am not sure what the transmission and rest of the drivetrain would do with more power than this is putting out so if you do go crazy to 400+HP you'd better budget for a new tranny and differential too. These are designed to match the power of the engines they are mated to. I think you can get away with a marginal increase, like the speedtuning chip delivers, but if you go all out don't expect the rest of it to hold up that well.

If you want Muscle buy an AMG gas car. My C43 does 0-60 in under 6 seconds and still delivers 20 MPG city/27 Highway.

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz