Do I need bigger valve springs?

turninheadz94

turninheadz94

casey ross
Joined
Mar 14, 2011
Messages
128
I'm rebuilding my motor and wondering if I need heavier than 60lb springs for the 181-210 cam I'm going to run, don't plan on going past 3900rpms. I had around 75 psi boost before.
 
Sure why not when you get into high boost you need more spring to keep your intake valves closed. And its best to get springs that will hold up to what ever the lift of your cam is. I had 60 lb springs and a 181-210 cam once running 87 psi of boost had valve float and had cracked most of the valve spring keepers.
 
The reason Cummins calls it a 60lb spring ts because it takes 60psi of port pressure (boost) to lift the valve off the seat with that spring.

While you have pressure on the other side of the valve at times to offset it, think about how close that seems to floating valves and potentially throwing a scrap iron fit.



Valve springs are cheap in the grand scheme of things.
 
Another thing that I hadn't thought of in the past, Cummins uses that spring for the exhaust. Since the intake valve is bigger in diameter, it takes less than 60psi to lift off the seat when used on a intake valve.
 
So what would be a good spring rate for me? I think cpp has 150lb valve springs now and I already have billet retainers and locks
 
turninheadz94 said:
So what would be a good spring rate for me? I think cpp has 150lb valve springs now and I already have billet retainers and locks
Click to expand...

I think they have good stuff. I always call and get the info on the spring if they don't post it just to be sure. I think 150lb springs will work fine.
 
A set of 150# springs from CPP is $120. A set of 60# springs is also around $120 from most dealers. IMHO, you might as well get the heavier springs so that you can turn more RPMs without having to worry about valve float and you'll be spending about the same amount. I know Dynomite Diesel makes a set of 90# springs but they're $200. Might as well go with the 150# springs. Just my opinion.

Jared
 
I have pax brake 60psi springs so are those 150' on the seat too? I was running 70-75psi with 2 boost leaks on both turbos, had 2 bolts push out of the turbine housing and on the ht60 there was a bolt missing. So I'm guessing I'm around 80-90psi
 
I realize they are the same lol, so I'm not gonna put the same exact thing, just don't see what Hamiltons 110's and everybody else's is the difference
 
The 150lb springs being sold are the Cummins 60psi spring, the stock Cummins spring is ~ 90lbs @ the seat. The aftermarket springs are beehive using a 10* lock/retainer setup which is where the real advantage is, and the seat pressure is a bit higher ~ 160-175lbs @ the seat.

110lb springs are for a 24v, and most forget that means a total of 220lbs @ the seat for the combined load on the bridge/rocker and pushrod.

The aftermarket retainers sold for the Cummins springs helps keep the locks from pulling through the retainer, Haisely uses a 10* lock/retainer and EEP uses an 8* lock/retainer.
 
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