As the previous post said, a list of your mods would be helpful. A short answere without knowing your mods would be depends on how much money your willing to spend. I am not done doing things to my car and I already have a JMS chip. I got it because I got tired of hitting the rev limiter with my 4.10's. When I do a few mods I will need to recal my chip (that is where the extra money comes in) for those mods. If I did the mods first and then got the chip I woudl not need the recal. I believe when I purchased the chip it was $50 for a recal but that was 3 years ago so it may be more now. In hind sight I am glad I got the chip when I did because mods to the car have been on hold due to building a house. I have been purchasing new mods but have not installed due to trying to minimize the amout of times I need to recal. It will definately cost more in the long run if you purchase the chip before completing your project (if there is such a thing).