I recently purchased stock pipes for my 86 4runner 22re. These stock pipes are around 1.5". After reading a few threads, most are saying to go with 2.25" or 2.5" pipes. What type of performance should I expect from my 1.5" pipes? Is this bad? and what muffler should I run? I have a friend that has a flowmaster 44 and I would like to have that, but will it work on my setup?