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Nos valve springs

BuickGN

BuickGN

TTA# 130
Was thinking of using the LT1 Nos upgrade Springs 3927142. Are these acceptable to use with a stock cam?
(105 seat pressure at 1.70)
 
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They are acceptable but a little too much spring pressure for my liking on a flat tappet cam.

There are better choices from Comp cams, like the 980's for street use and 981s for street/strip use.

whatever you decide, it probably goes without saying, but run a ZDDP additive in your oil.


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Actually I think it's one like 105 seat pressure. I use Amsoil in all my engines. Do you put that additive even with synthetic?
WS6 said:
They are acceptable but a little too much spring pressure for my liking on a flat tappet cam.

There are better choices from Comp cams, like the 980's for street use and 981s for street/strip use.

whatever you decide, it probably goes without saying, but run a ZDDP additive in your oil.


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BuickGN said:
Do you put that additive even with synthetic?
Click to expand...

I would!

Look, I know that ZDDP is controversial and has been discussed ad nauseum here and over at TB.com.

But the fact of the matter is that Zinc Dialkyl Dithio Phosphate levels in any passenger car oil has been reduced as means to keep catalytic convertors from going bad before 100K miles....which the Fed says they must last that long.

So....we know that Zinc Dialkyl Dithio Phosphate is the sacrifical component(layer) in severe metal to metal contact surfaces such as the "scrub" of the lifter on a cam lobe, and we know that adding ZDDP to motor oil brings those levels back up to what they were before the Fed mandate...so the question should be "why not use it?" regardless of conventional or synthetic oil uasage.

I mean we're talking about $6-$8 additional to the cost of an oil change VS. a couple wiped cam lobes and lifter bases that have spread metal throught the motor.

I mean here's how much I use...one bottle per oil change and if I go to the track and make a dozen or so passes on that oil I will even add a half bottle more to the existing oil just to replace what was "sacrificed" during that punishment...after all Zinc Dialkyl Dithio Phosphate is a consumed part of the oil, hence the mandate,because it wreaks havoc on a catalytic converter.

So...yes...even with synthetic...para or fully.


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WS6 said:
I would!

Look, I know that ZDDP is controversial and has been discussed ad nauseum here and over at TB.com.

But the fact of the matter is that Zinc Dialkyl Dithio Phosphate levels in any passenger car oil has been reduced as means to keep catalytic convertors from going bad before 100K miles....which the Fed says they must last that long.

So....we know that Zinc Dialkyl Dithio Phosphate is the sacrifical component(layer) in severe metal to metal contact surfaces such as the "scrub" of the lifter on a cam lobe, and we know that adding ZDDP to motor oil brings those levels back up to what they were before the Fed mandate...so the question should be "why not use it?" regardless of conventional or synthetic oil uasage.

I mean we're talking about $6-$8 additional to the cost of an oil change VS. a couple wiped cam lobes and lifter bases that have spread metal throught the motor.

I mean here's how much I use...one bottle per oil change and if I go to the track and make a dozen or so passes on that oil I will even add a half bottle more to the existing oil just to replace what was "sacrificed" during that punishment...after all Zinc Dialkyl Dithio Phosphate is a consumed part of the oil, hence the mandate,because it wreaks havoc on a catalytic converter.

So...yes...even with synthetic...para or fully.


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will be putting it on the menu. Thanks for the input
 
Well said about zddp, and I favor the Comp 980's. Can't remember all the seat pressure details but the stockers are around 80-85# iirc. When I did mine in the GN, which had the retainer cups, not sure if the TTA has them, but I kept the cups, removed the internal dampener spring in the 980s, then the added height change due to the cups thickness put the spring pressure just barely above stock values, maybe 5# more. ..that was years ago, at least 12 years ago which is why I can't remember the details, but no issues. Seems like the 980s with the internal spring were about 10# more than stock. With the stock cam there is no need for added seat pressure and these motors don't rev to the moon to begin with.
 
I would stay as close to stock spring pressure as well ... new fresh springs will make a difference.

It's interesting any discussions about oil ... Bill Owen told me they built a test setup somehow and he could prove synthetic oil was superior and he strongly recommended running Mobile 1 (I think he said) synthetic ...
 
I am a huge believer in trusting the GM engineers. I rarely will do anything outside their parameters on stock parts.

However, I will go against their recommendations in this instance due to the cars being close to 25 years old. The oil that Bill Owens tested is no longer available. The product spec sheets have changed and the Mobil 1 sold today no longer has the same properties and additives it did in the 80's. This is an irrefutable fact. Am I right? Who knows, but I haven't had issues doing it my way. All of us change the oil WAYYYY too often anyways, so I think running conventional for our use is not a problem at all.

My opinion anyway and we all know what opinions are like!
 
I'm going to trust the engineers and use the LT1 Springs. Guess I will be your test guinea pig on this item. I already use Amsoil 10W 30 in my vehicle which I have used for years and change the oil every year since I stored over the winter. I'm also going to add the ZDDP. I'll see how it goes. As years go by and the Springs loosen up, it'll settle into the correct spring pressure. I think the Amsoil combination with the ZDDP will hold it out.
 
I use Amsoil in new vehicles. Awesome product!

The LT1 springs are 20 lbs heavier than the factory stock springs. Their seat pressure is 110# installed at 1.700.

You'll most likely probably be fine. Just my opinion!
 
I've seen two seat pressure listed for the spring. 105 and 110. How do you know which was which? Doesn't matter from earlier years or newer years?
 
Well, I have no idea what the spring pressure is at max lift for a stock spring since pressure is usually quoted at the install height which means the valve is closed. You might want to see what those LT1 springs are at max lift of the stock cam also, they may only be 20# more at install height, but may be much more at max lift than a stocker, you will want to be concerned about that also. Back in the early days, the LT1 was a popular choice, but lots of folks have wiped their cams too. I see no reason to compromise this as the stock cam is not aggressive by any means and does not need any added pressure than what it was stock. You'll notice a huge difference just in refreshing the 24 yr old springs either way. The pressures you have seen may be different depending on the install height quoted, the height and pressure go hand in hand.
 
I got a note that Sealed Power VS744 would be the stock factory correct replacements ... not used them myself and have not looked at the spring rate etc. but thought I'll share what I found some time ago. (in the end I went with a full roller setup and Comps beehive springs instead).

My GM part books don't list the springs in them for some reason so can't help with the GM part number I'm afraid.
 
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The VS-744's are 78 lbs according to the spec sheet at 1.700" install height-ie what you'll have.

15% less than 980's.
29% less than LT1's.
 
Keep in mind that AMSOIL makes many oils and most of them comply with the API SN limit of phosphorus (800 ppm). For the types of engines discussed in this thread, this is the only AMSOIL engine oil I'd consider:

AMSOIL Z-ROD 10w30 Synthetic Motor Oil (Product Code ZRTQT)
(zinc – 1440 ppm, phosphorus 1320 ppm)

More than happy to get AMSOIL products for forum members at dealer wholesale pricing, about 25% below retail, via the AMSOIL Preferred Customer Program. Drop me a PM if interested. :cheers:
 
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