Q: ok..so the axle that comes in the SJ kit isnt the speedpassion one?
A: Correct, it is different, it is a two piece more similar to the tamiya one
Q:do rcart sell the speedpassion one? as well as the carbon reinforced bits?
A: No, I order direct from speedpassion, http://shop.speedpowerrc.com/
Q:also I can get the tresery sp1 for a great price locally but only a few dollars less than the SJ version and is it really worth getting the SJ version?
A: YES, get the Street Jam it is MUCH better. The rear has more grip and with any F1, like the Speedpassion, that uses a rear center pivot, it tends to need adjustment every race round to be at it's best. The SJ is a different better design it doesn't move with crashes or hits etc
The SJ is a Speedpassion front end and a new better rear end. The rear is totally different except the Speedpassion rear axle is compatible and better.