Is there a diff in the stiffness of an intake and an exhaust valve spring from crower? I have heard the stock valve springs of an ITR are different, but I couldīnt find any colored marks on the springs, either on the ITRīs and on the Crower.

 

comonīguys! nobody know it?

 

I can only tell you what I did with mine, if you wish to go over your stock limit you must increase the seat pressure, spring rate and if using a big cam make sure that the spring can handle the coil bind, basically increase the intake and exhaust the same rate, intake valves apply abt 20PSI more pressure throughout. there are a couple of springs out there that will grind your cam and ruin your valve seats so watch out, increase your spring pressure no more than about 40PSI.

 

Thanks!