I ahve now have my manual boost controller installed for about 10 days now and thought I would post my results. After first installing the controller I noticed a definate increase in power only in the upper end of power as crushers had suggested. While going up a hill under load there was a lot more power and that power seems to not drop off until I reach higher rpms. I also have had less black smoke under full load which tells me I am using that fuel now instead of wasting it,I have yet to turn up my fuel asI wanted to see how it performed without doing that. All in all I am very happy with the controller but have a few questions. I went away to my cabin this weekend, about a 500 km drive from vancouver to 70 mile house area. On the way there the truck performed flawlessly. It under load would come up to the 12 lb mark and sit there no problems. On the way home today I started to notice that the boost was acting erratic sometimes(all of this under load) going to 14lbs then dropping off to 6 then slowly rising to 12 then maybe dropping to 10 and then sometimes coming up to 12 and then holding there like it should. I am wondering what could be some of the causes of this. The truck itself seemed to be running great and only noticed once where it felt like Iwas under powered while being under load and what should be a high boost senario. Am I doing damage,should I remove this controller gizmo or is it maybe a leak under higher boost conditions(I didnt fell like the was any loose clamps and such?