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New Valve Springs?

blkaplan said:
The biggest issue I have heard of with the stock springs is if the car has sat for a while, the spring can get rusty and gets pitting. When you get the car back to life, the spring will fatigue from the pitting. If the free length is fine and there's no rust, those springs will go and go.
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Rusty springs go straight into the recycle bin, every single time :nod:
Heck, even suspension springs will break if they're being used close to coil bind and have rust. The safety factor on a spring is really low for most applications.
 
@culberro, any qualms about running the square tooth belt with the BTR et al springs?

Also, can you put the rally car back, chubby Howard the Duck freaks me out.
 
shoestring said:
@culberro, any qualms about running the square tooth belt with the BTR et al springs?

Also, can you put the rally car back, chubby Howard the Duck freaks me out.
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No issues with the square tooth. I like to get the belts just a bit more snug than the tensioner can.
The old 8v rally car was square tooth with dual springs that were 150lbs on the seat. No issues with the belt slipping ever, even over 8k.

I'll find something else for an avatar... I just wanted to scare the children :rofl:
 
I guess that's very true. That springs have different outcomes in OHC vs. push rod.

The BTR springs were the cheapest I've found so far.

The 242 was sitting in open weather for a fair amount of time. I'll check the springs carefully for any rust.
 
So if I were to put BTR springs in my car, would it actually lose low end, but gain high end through higher RPMs?

Trying to learn a bit more.:nod:
 
culberro said:
Nothing would change...
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Okay. I was going off some forum discussion I found (not TB) and that's what they were saying. Clearly misinformation.

Springs change nothing, except allow for more aggressive camshafts and the like? But on the opposing side, the stronger the spring, the more potential wear on all the moving parts.

Then there's benefit for lighter retainers and springs, as well, and that's just potential for higher RPM ramp speed?
 
No performance difference at all, should just facilitate higher RPM by virtue of better valve control/lighter valvetrain mass. Unless you're already floating valves...

Camshaft ramp speed is more a function of bucket diameter/design than anything.
 
OldCarNewTricks said:
Okay. I was going off some forum discussion I found (not TB) and that's what they were saying. Clearly misinformation.
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If you're running really heavy springs on an improperly setup pushrod engine, you can definitely reduce lift and duration by a significant amount.
On a direct acting OHC engine, you're only dealing with a slight (and I mean very slight) frictional loss.

Also, with a rocker arm ratio of ~1.5:1, the force acting on the lifter is 50% more than what is acting on the valve, and the lifter is 1/2 the diameter of a Volvo bucket. That means you have significantly higher contact stress and wear on something like a flat tappet V8.

All that to say, that on a Volvo 8v the likelihood of destroying a cam from too stiff of springs is almost impossible.
 
2manyturbos said:
Free length? Whatever happened to using a valve spring pressure tester?
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Free length is a reasonable way to check that's pretty simple and only requires a ruler or a pair of calipers.

Since the steel wire doesn't get stiffer or softer as it gets older (Young's modulus stays the same). The free length slowly decreases in height, which decreases the spring force at a given installed height.

How many people have a valve spring testing tool and get it calibrated regularly?
 
There was an awesome article in Super Stock and Drag Racing Magazine from about 20 years ago that extolled the virtues of beehive springs in which David Vizard runs a small Chevy to like 8200 rpm or something on a single spring. He includes some maths and stuff and I've never used straight springs since.

And this is from 20 years ago.
 
shoestring said:
There was an awesome article in Super Stock and Drag Racing Magazine from about 20 years ago that extolled the virtues of beehive springs in which David Vizard runs a small Chevy to like 8200 rpm or something on a single spring. He includes some maths and stuff and I've never used straight springs since.

And this is from 20 years ago.
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They're really great, their downside is that they are limited on diameter/length/rate.... and the cost.
 
I recently had the Yoshifab beehive springs installed on a 531 head. When I first had the head built I went for the high seat pressure dual Isky springs. I wanted to build an 8500rpm engine. Then I woke up and realized I needed something different. The group buy happened at just the right time. Looking forward to trying out the head in the not to distant future.
 
I've been looking around for OE style beehive springs that will work, and I'm finding that it's difficult finding a spring that will not bind in our redblocks.
 
OldCarNewTricks said:
I've been looking around for OE style beehive springs that will work, and I'm finding that it's difficult finding a spring that will not bind in our redblocks.
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Yep. The installed height is pretty low, and there are some large cams that are used.
You can change installed height with different retainers as well, to an extent.
 
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