[Mike Taylor 3601]

I can say,I have ran under the old style rules spring pressure and lift, duration and overlap and it having to check.... and I have and do run under current rules....
I would pick current rules on cam,lifters and springs...been there done the stock pressure spring,which was checked...and duration overlap....
my IHRA pure stock combo 305/160/230 ABSOLUTELY ate springs and valves and it LOVED the taste of them... if nothing went wrong about 35-50 runs heads were coming off for valve job, valves and springs....

present rule stocker... I have one right now in D3 with 3 seasons on engine and same springs... had one with 500 runs on cam and lifters...had 300+repeatedly

I will take current rules on springs...
however if I built another stocker it would be a roller cam car... no other reason than eliminating cam break in...