HI Guys again .. IF there no Valve Issues on 1987 MOdel SDL 300 How can I do to restores performance in this Engine? I start already changing the air filter, Of course I have to Change the Diesel Filters but any thing Else?

THe car is running good but it is slow at accelerating and does not seems to pass 65MPH on Highway, It is hard I had to put full throttle and it is dificult. Any of your beatifull comments will be very well use

Fernando Q