if you do try going with a 4 mil long rod with stock ported cylinders,cool head or noss with 18cc cut domes on alky.did one 3 weeks ago and it runs good.4.20's in 300ft.there are 535 cheeta's,421 cubs that are no faster.son's is stock stroke,stock ported cylinders on alky past weekend went 4.40 rich and not good 60 ft.s.i have not seen too good a results from trinity's setups.jmo.