Sirio evo 4 sti is a great motor. On my 4th gal never had a problem with it, Idles great.Great power all the way around, but in a truggy most people go with a cl7b sti for their truggy but for buggy its fast enough.If u go with a sirio evo 4 sti u need the 2013 pipe will give you the best low end and hardly lose any top end.My track has a 200ft straight and would not be pass by nobody with a 8 pound d8.
.Parts are very hard to come by since trinity took over.Smooth motor botttom to top and rev to the moon.My run time is about 8.30 to 8.45 with 8 mm insert am sure I can get much better a 7mm or 6.5 but never needed it good . If u need a connecting rod I think u can use a trinty extech rod or a werk b7 pro but dont hold me to it.