[SA] double valve springs vs single.

[Toyyyga]

I've been told by a reputable tuner that in my ls3 with a mild cam I would definately lose a little power after installing double valve springs. That you will always make more power with a single until you go bigger cam bigger lift. Opinions please?

 

[gossie]

If it aint broke, don't fix it, as they say in the classics. I can't believe it would be valve bouncing on the singles. Is it?
Double valve springs will use more energy and with more pressure on the valve train will wear parts out faster.

 

[ari666]

do LS3's have beehives?

 

[07GTS]

ls3 has single spring, u won't loose power but like said u will have more pressure on all associated components, unless u have valve bounce or put a bigger cam in there would be no reason to change them, if u have mild cam then u should change to better springs, some like duels because if one brakes then the other spring stops it from falling in the cylinder...

 

[lowandslow]

A friend of mine broke an inner spring when he was on his way back from Tasmania in his Blown 6lt VE. Lucky he had fitted duals when he done the cam swap otherwise it could have gotten messy. Pretty sure he limped it from near the Victoria border all the way to Wollongong near Sydney.

 

['ssv']

Single springs wear out fairly quickly, I belive they are ment to be replaced every 20,000.

 

[Ian Johnston]

Where did you hear that crap from???

 

[somefool]

There is no way in hell that valve springs would have to be replaced as often as a service item. They dont 'wear', they just weaken/lose their tension over time. Over a long time. Unless they are poor quality items, obviously. Replace them when you do a rebuild/ or a cam upgrade (in which case they would become unsuitable for purpose anyway)

 

['ssv']

Wear out = loose tention.
ive seen it happen, a collet/keeper snap and drop the valve.

 

[PIR4TE]

Go the singles, especially with your lighter intake valves and 'mild' cam. Of course it depends on whatever 'mild' actually means technically, I'm assuming mild increase in duration else what's the point?

I use PAC 1500 series plus lightweight, thin moly rods. Swapping these alone retaining the stock cam will let you rev past 6400 with total control (no bounce), no undue stress / noise plus give excellent economy.

Consider PAC1511 drop in beehive LS spring, the best drop beehive spring available.
Features:
• 130lbs @ 1.800”
• 384lbs @ 1.140”
• Spring rate 385lbs per inch
• Coil bind 1.080”
• Max valve lift .660”
• Frequency 32952
• Nitride surface heat treat
• Polished
• Nano peen
• Extreme high levels of fatigue life