I have a T5z behind my 347 stroker and have not had any problems yet. Although this completely depends on how you drive the car. If you do any track time and plan to race, then T5 is probably not a good choice. But if you are just into "spirited" driving as I am, then I think you will find it fine. Note the T5z and or World Class has some beefier/stronger components, so you shoudl seek one of these out if going with a T5. If you definately want/need an overdrive transmission, the T5 is the only one currently that does NOT require any surgery to get the proper pinion angle. This is a pretty heavily covered topic on this forum, just do a little searching and you will have plenty to read in order to draw your own conlcusion.