I recently purchased a set of assembled dart 225's. I'm considering running a high lift cam with them and would need to upgrade the springs to something that could handle .650" lift with an aggresive ramp rate. I'm assuming I would also have to swap out my retainers to match the springs, but I read somewhere that the valve stems on the dart heads are not the same diameter as LS1/LS6 heads, but don't know if this is in fact the case. If they are different, I would need retainers/locks made to match the valve stem diameter. Can anyone confirm if they are the same size or not?

What I would like to do is just go to a set of Patriot or Manly dual spring/retainers/locks. Can I do this, and if not what other options do I have?

 

Dart looked at other valve sizes early in their development, but in the end the Darts come with the standard 8mm valve stems. You should be able to install the duals, although the PSI beehives that come with the Darts are an excellent valve spring.

Are these new heads?

 

A set our Patriot Gold Xtreme springs will work great for this application. We can do this set up for the 8mm valve stem or the 11/32" if need be. The complete kit with the ti retainers, machined locks, seals, bases, etc. is only $279.50.

 

Awesome, thanks. I will give you a call if I decide to go this route.

Vettenuts: yes they are brand new right out of the box. I'm just not yet decided on my cam choice and contemplating one of the higher lift cams, in the .640 range. I know the springs that come on them are good, that is one of the reasons I bought them. But they are only good to .625 lift and it sounds like the high lift cams really work well with these heads, so I'm not yet decided on which way to go.

 

Sent PM.