Has anyone used them? Are they any good? If so how does it all actually work so they come up with a good tune for your vehicle? I am not the first owner of the car and Im not sure what all if anything has been done internally to it. I know the externals but thats about the end of it.

 

I used them for my engine swap, and Vince was very helpful. I started off not knowing what I needed, and Vince spent plenty of phone time discussing what we could/would do for the tune. Even as far as offering to email a updated tune for some changes I made within the first week after getting the first tune installed. For my money Trifecta Performance was great! Props in my sig also.