I see people say that certain valvesprings are too stiff for their applications, just wondering what this criteria is based on.

How do people know how stiff a valvespring is unless they have spring pressure testing machines/ tools and what is the consequences of running too stiff a valvetrain?

 

All that comes to mind is:

1. Stiffer spring = greater Cam resistance = HP loss

2. Stiffer spring = greater Cam/Rocker pad wear


But I've never heard people gripe about having too stiff a spring. The benefits (no valve float) still outweigh the costs (slight power loss).

 

Thanks for the info. That pretty much confirm what I was thinking, just that I was afraid that too stiff a spring may stretch a valve or even pull it into the head. On Hondas this sounds possible since the valve are steel and the heads are aluminum.

 

But the valve seats are steel. The valves never actually contact any aluminum.

 

too much spring will cause the cams to eat into the head eventually. Just like the old 87 CRX Si engine. They took the EW3 carbuerated engine and stuck a dual valve spring higher lift cam into it and fuel injected it and the cams always ate into the heads after 100k.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IndySporty &raquo;</TD></TR><TR><TD CLASS="quote">too much will cause the cams to eat into the head </TD></TR></TABLE>


What does that mean?

 

I imagine what you are saying is the journals or cam cap went to an extreme out of round condition....? This is the only place the cams contact the head. Otherwise its all rocker arms.