Original Stock Valve Springs

hytorksc

Registered User
In general, how long do original stock valve springs last in an SC in terms of mileage before they need replacing?

Is there any danger of the springs breaking with an SC engine going over 200k miles?
 
OEM Cam?

hytorksc said:
In general, how long do original stock valve springs last in an SC in terms of mileage before they need replacing?
Are you using an OEM cam, or an aftermarket cam?

68COUGAR
 
I asked this same question a while back. I have a bird that had 230,000 miles on it before swapping the heads from another bird. I'm going to get the springs tested in a few weeks to see the difference between the stock rating, 230,000 miles, and 140,000 miles. Hopefully that will shed some light on the life-span of these springs.


btw, I ordered a set of replacement springs from SBI through an engine builder for 34 bucks. not a bad deal. but, we'll see how long they hold up.

also, i've heard on here that springs will loose thier "strength" over time and not necessarily break. But I can only speak for 230,000 miles. after that much use, I dont' know.
 
so if the springs lose some of their strength eventually, then i imagine there still would be little or no effect on how the engine runs or performs- just a little less spring resistance opening the valves. but if running extremely high boost levels, the valves may start to "float" a little sooner than normal. so i guess running an SC engine up to 230k miles would be the latest time to replace the springs as a precaution- or just install new heads or springs right now.
 
that's sounds like what I read when I searched the posts too.

I've never had a chance to feel valve float (not that I've known, so... I don't know). but the theory sounds true, and I've read it in a book, so at least some other guy thinks that's the theory too.
 
Back
Top