Hey guys I'm still fairly new to the rc world. I'm looking at different engines for my nitro rustler. Will the engines built with tmaxx bolt pattern fit? Some of the engines I have looked at have been discontinued( picco red dot ,o.s. 18tm) so what will fit. I will give up the ez start if need be. I put some huge tires on it so I need the power to run them. I have a 3.3 in it but I'm not impressed. I have the stock pipe on it that's for the 2.5. How much will it help to upgrade the pipe?