I was curious at what point is it necessary to change out the valves? If I am planning on upgrading camshafts and valvesprings/retainers is it necessary to change valves as well? My plans would be to go to a speed density based engine management then get jun 272's and supporting springs/retainers. I will eventually go big turbo and stroker kit, etc...

valves or no valves?? what can the stock ones handle?? thank you very much.

 

The stock valves could handle anything you throw at them.

Bigger valves are obviously needed if you port the head but otherwise the stock ones would be fine.

 

with those JUN cams, which springs are you going to use? I see deals on getting them with either the JUN springs or Supertech springs. I want to know which ones will work the best with the JUN cams.

 

I dont know for sure, but the JUN springs would probably work best with their cams. Usualy companies design their products to work well with each other. Have you looked into the revolver set? I have them on my car now and I really like them. The throttle response is great with them.

 

thats exactly what I am thinking. Yes...I have looked at the Revolvers and they have that high ramp up profile as well if I remember the thread about them. Thats what I desire. I just dont know how proven the Revolver cams are at the moment and is the only reason I am leaning towards the Jun considering the massive price difference. I could buy two full sets of Revovler's for the price of one set of the Jun cams/springs.


Sorry to hijack your thread.....

 

Dont appologize its cool. I am still debating between the revolver or the Jun cams. I had pretty much planned on getting the dual springs from springtech. The whole key is the higher ramp up profile like you said and both the revolver and jun have them. For price reasons I think I may go with the revolver set.

LetItBreath--where did you get your revolvers from?? and did you put new springs in when you replaced? thanks!

 

I think new springs are needed with jun cams.

 

This is not true the stock head is only good up to 650 hp anything past that is just going to go blank and it will just start to lose power. Ive talk to 4 people about this one of the people owned a porting shop and the other worked a shop or owned the shop. One shop ran a test they bought it up to 649hp and 596tq on 100oct with a 40R so he put some C16 and changed the map to the C16 setting and lost over 35hp and 57tq. Next day he ripped it out to get a 1mm port. Placed the car back on the dyno same map it was 10 deg less in the dyno room he made 745hp with 37pounds of boost 657tq so there are limits.

 

without a doubt. that ramp profile requires it, just like the revolvers. Buschur sells revolvers w/springs and retainers (from Revolver) for $750 I believe. Double check that on his site.

 

I called AMS today and talked with them on the issue of springs. They said the Supertech's are fine and that is what they run on the cars with Jun cams to include the 900hp Evo's

 

He asked what they could handle... They wont break from 2000 horses... they may not flow enough for they will handle it .

As for how much will they flow before starting to restrict the airflow horribly.. yes i would guess in the 650 range which is fine for pretty much anyone here. If he plans on making more than 650 I dont think the valves are going to be his biggest concerns

 

The stock valve train will probably hold up to 8000 rpm, though I personally wouldn't want to push it that high (at least not for long). With higher lift cams, such as Jun or Revolver, you will need to upgrade your valvetrain (e.g. Supertech, Revolver, Jun, etc.). You will also need to upgrade your valvetrain (and engine internals) if you plan on revving much past 8000 rpm.

l8r)