Do these add timing and fuel or just fuel. I was going to
buy a code scanner / reader and thought for a little more
money I could get one of then and load the 40HP program
to "stack" with my Van Aaken.But I don't want anymore
additional timing just more fuel.

 

both alter fuel and timing. The have ran both and the Superchips ran much better than the hypertech, especially stacked with another box. If you do a search there has been a lot of posts on this topic. If you want a code scanner / reader it is already built into your truck. Simply cycle your key 3 times and leave it in the on position and it will display DTC's in ECM and PCM in the digital odometer display. Then go to web pages like this one http://netdp.proboards14.com/index.c...num=1057800048

to look up what the code is. If you already have the vanaken and want about 40HP i would definetly go with some Bosch RV Injectors. That is the best towing setup with the stock turbo.

 

rv injectors for towing. what is the benefit of adding these injectors? more power for pulling hills?
better economy? lower EGTs?

just curios sorry for butting in.

 

RV Injectors are basically the first step above stock injectors. Typical gains are 40 rwhp. As for economy some people report about 1 mpg gain when unloaded. They will not lower EGT's, no product that adds fuel will lower them. They are great injectors if you tow heavy with a stock turbo because you can easily control the heat. They are relativily in-expensive and when combined with edge ez or tuner or other low horsepower boxes your EGT's are kept in line fairly well.