I use the stock 5 hole Piston with 30wt front and 25wt rear I must say this thing is on rails at my local indoor track... i could have TQ but screws backed off on my steering rack.. so I started on the back of the pack on the A main... took the lead only after 5 laps and never look back and put the whole field a lap down... not to mention this is the first time my SC6 seen the track with one practice on it the day of the race and I never race 2wd SCT ever. All I can say is wow! All the fast guys on our expert 2wd SCT class just got blown away how SC6 handles. I can point the darn truck anywhere I want it to and it just on rails..