I would not say you could not get 80hp 80tq for $2500. Depends what products you want from what company and how much you want to pay. I know a local E55 that did the Heat Exchanger and CM30 pump from some guy here on the web for $450 shipped then got a new ASP for $800 from me, then got the new shorty headers no sure of brand but they were new to the market for $1000 made 30rwhp and base tune from LET for $500 on special, and the car made 500rwhp and 550rwtq on dynojet on a 96deg day. So for $2750 he got the job done 80-90rwhp over a stock car not that headers i would have done when there is long tubes or Kleemans out there for $1500 but cost more money.

What does Mercedes do to the engine to upgrade the horsepower to 530?? HP and what is required to upgrade an stock SL55?

Can I install this kit myself?

Can I install the evo kit myself?

Which kit? Depending on your level of technical expertise and tools, you may be able to, but we HIGHLY recommend an experienced tech for the pulley and somewhat for the headers.

thanks
Brad