I have read and read and cannot come to a conclusion. Do you need 60lb intake valves? Is it actually necessary unless your running a high amount of boost? And if so at what boost level do they become necessary?

Kinda just starting a little discussion on this and see what comes out of it.
Also from my point of view this is just a dd street driven truck with nothing more than some street flogging.

 

No one?

 

Well if you wanna get a 4GSK than you would need the 60lb springs unless you want to risk floating the valves. They are more or less a safety precaution and give you a peace of mind when adding more power and boost. But thats just my 2 cents

 

If you spin it harder that 3200 or are making 50 or more lbs you should probably have them.

 

I've heard that you don't need them on the intake, even at higher RPM since with the valve timing the way it is, your piston is never chasing the intake valve as it is the exhaust valve (if that makes sense). Although, IMO, I would do it. Better safe than sorry.

 

unless you are doing 5,000 rpms, you do not need these on the intake side, 60lbs springs is not a from the high horsepower side, it comes from the Heavy duty industrial side, the exhaust side has the 60lbs springs becasue they go into machines like dozers, back hoes, skidsteers, etc; they also used them in the freight trucks that have exhaust brakes on them.

I have a skidsteer and it turns over 3800 rpm and the intake springs are still the 30lb stock and the exhaust are the 60lbs stock springs from cummins, have not floated a valve yet, going on 3100 hrs.

but with all that said,on my truck, I even put 60lbs springs on my intake as well, just as mechanicl diesel said "peace of mind"

 

This is the kinda answers i was looking for to kinda clear up what i was starting to beleive was a myth about "needing" valve springs on the intake side. I agree that it is a piece of mind but at the same time i guess you technically dont need them.

 

Higher manifold pressures will try to push the valve open.

 

Correct unless your running high amounts of boost. I would say anything above what 50?

 

Somewhere around there.