List of best mods for added horsepower
#26
There are some members on an SLK forum (different site - don't recall but slk was in the site name) that have posted their dyno results. They seemed about right. Both tuners originally sold those kits for the SLK crowd. For the W203/4 they required extra work to get them to fit, specially the collectors & down-pipes. These new headers though should be much easier to install but will still require some cutting and welding since the outlet pipes on the headers are almost 3/4" larger.
I think the performance gain is two fold. First slightly less back pressure due to the larger piping, second the OE headers allows the gases to mix right away as soon as they leave the engine, whereas the these headers have much longer equal length tubing and then mixes the exhaust gas at a central point. From my limited knowledge, the key to good/tuned headers is that they allow the gases to flow from the exhaust port on the engine without interference all the way to the collector. With the cast iron/cost-effective OE headers the gases mix right away and the pressure waves interfere with one another and this also causes back pressure and changes in exhaust velocity.
But most importantly...they should sound pretty badass
I think the performance gain is two fold. First slightly less back pressure due to the larger piping, second the OE headers allows the gases to mix right away as soon as they leave the engine, whereas the these headers have much longer equal length tubing and then mixes the exhaust gas at a central point. From my limited knowledge, the key to good/tuned headers is that they allow the gases to flow from the exhaust port on the engine without interference all the way to the collector. With the cast iron/cost-effective OE headers the gases mix right away and the pressure waves interfere with one another and this also causes back pressure and changes in exhaust velocity.
But most importantly...they should sound pretty badass
DI is the reason the SLK's make around 300hp from the factory and the 350's don't.
#27
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2014 Ghibli S Q4 & 2008 C350
I don't think DI is here yet for the SLK or SL. I heard it was possible they might for the MY2011. The current M272 SL/SLK350 engine makes more power because it has a different intake, cams and exhaust plus a modified tune on the ecu. The redline was increased to 7200 and most of the added HP is up high.
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2014 Ghibli S Q4 & 2008 C350
Yeah, a full exhause redo would sound pretty sweet.
Do any tuners customize the tune for individual cars? If you get a full intake and exhaust rework, it seems the ECU mod could be tweaked to really benefit all the extra work. The AMG Performance manager at the Buckhead center says they do that on site but I have not really dug much deeper for the details.
Do any tuners customize the tune for individual cars? If you get a full intake and exhaust rework, it seems the ECU mod could be tweaked to really benefit all the extra work. The AMG Performance manager at the Buckhead center says they do that on site but I have not really dug much deeper for the details.
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2014 Ghibli S Q4 & 2008 C350
Not sure yet but the K3 kit is about $6300 EUR and I think that includes VAT. So I'm not sure of the USD price once you back out the VAT tax. But probably between $8000-8300.
The camshafts are priced about $3700 EUR. The headers are $1600 EUR if I recall but again I think those includes VAT so once you back that out and convert the price, . Cory is supposed to email me final USD pricing once it's available.
The camshafts are priced about $3700 EUR. The headers are $1600 EUR if I recall but again I think those includes VAT so once you back that out and convert the price, . Cory is supposed to email me final USD pricing once it's available.
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Mercedes Benz
These motors can only squeeze out so much horsepower... Eitherway you go for an ECU re-program, I'm sure you'll be happy with the results. The only way to make real horsepower is to remote turbo... But, why? Might as well buy a c63. You can't supercharge this motor because of the compression and without seriously modifying the internals. The biggest problem for these cars are the manifolds. ECU/Headers is the best options for the car. Other than that it's not worth the hassle.
#36
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2008 C350 Benz, GLA250 4matic
Well I bought my C350 for 22000 with 50000 miles , and I've been in the automotive industry for a few years and I know some friends who have quoted me 5-6Gs for turbo or supercharging. So 28Gs for a C350 with hp in the 380+ range is a lot less than a c63 lol plus the insurance on the 63 is kille so it actually might be worth it for me. Lol
#38
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Well I bought my C350 for 22000 with 50000 miles , and I've been in the automotive industry for a few years and I know some friends who have quoted me 5-6Gs for turbo or supercharging. So 28Gs for a C350 with hp in the 380+ range is a lot less than a c63 lol plus the insurance on the 63 is kille so it actually might be worth it for me. Lol
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'11 C350 '13 F150 lariat
not worth the 5-6 grand. You can easily do headers a cam and some porting and tune the car for 100 octane sunoco and run 350+hp for 2-3 grand, not worth the TT or charger if its not factory installed. Could also do nitrous shot pretty easily for alot less and just use it when u need it. And there really is no room for a charger in there, motor sits too high. The remote turbo has been done but as said the reliability of the car goes to hell. You can get a used E55 or cls55 for under 30k that is already charged and can tune another 50 hp+ like nothing out of it. better to start over or grab a C32 if u like a C with a charger