Valve springs

[Ol' Ron]

I just found out that the Isky 85 valve spring has 85 ft/lbs of spring pressure at installed height. I have to admit, I always thought it had 65, and wondered why they called it the 85 valve spring. Sounds pretty stupid I guess, but the last time I used a set was back in the 60's when I removed a set of dual springs fron an Isky 404 cam and replaced them with the Isky single spring. I don't remember what they called it, at that time. I recently was asked how I get the 50/55 spring pressure on the chevy valves, at one time I could get LZ springs from JWL, and these worked quite well on the chevy valves, Using a .060" shim on the sock spring is all that's necessary on a stock valve.
Now with all that said, are people here actually using the Isky 95 springs in their street engines??? I don't think there's enough Zink in the world that can save these cams. A street engine rarely hits 4K and spends most of it's life under 3K. I just can't find the justification for using these springs. I hope I get some comment on this.
Ron

[tubman]

I have a set of the Isky springs on the MAX-1 in the 258" I just finished. As I have said in an earlier thread, it'll rev easily to 5500 and it seems to want to go a lot higher. I hope I don't have problems in the future.

I ran a bottle of GM "EOS" for break in, but nothing' fancier than my old reliable 10W/30 from Dollar General. You know, the stuff that says "Not to be used in engines made after 1985" on the label. I figure I should be OK.

[GOSFAST]

Hi Ron, really all depends on the actual I.H.

We use/sell a number of the Isky (185-G) springs during the course of the year. We get a nominal seat pressure of 70# @ 2.060" and a nominal open pressure (at about .340" lift) of 160#. These pressures have had no adverse effects on any of our own builds here. Many with 40,000 miles plus now!

Thanks, Gary in N.Y.

P.S. Having said this I would also add we sell many more of the "stock" replacement springs than we do on the Isky's, price being one factor and the OEM springs "get-the-job-done" fairly well in most applications. Haven't had a single complaint about any of the springs we use. When building the unit you simply need to know which spring will work best all-around.

[Brian]

I'm yet to hear of a flathead suffering 'valve bounce'. I just use stock progressive wound springs in all my builds. No problems

[Ol' Ron]

I'm sure the springs will work, that's not the issue. I just don't think their necessary. Most people aren't running at Bonneville , or a 100 lap feacher at the local dirt track.

[Frank Miller]

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I'm far from an expert but if you think about it you want to run the least seat pressure possible for the job. The more lift on the cam the faster the valve needs to close. The higher the rpm is the same effect. Seat pressure will also help with cooling the valve holding it tight to the seat. On compression the pressure will hold both valves closed giving more seat pressure. Excessive spring pressure will do nothing but create heat. I'm thinking unless you're running high rpm for extended periods of time you should be ok.
Here is a link with some interesting reading about what overheads run. They rev higher and valve float can be a problem. I remember the 289 Hipo engines had pads on the top of the piston to close the valve in case of valve float.
http://www.cranecams.com/bulletins_listview.php?s_id=16

[Tinker]

Think LZ are around 85. I have a ground cam and LZ springs. I sometimes wonder if that was a bad combo for me on stock crank, .60over, ford valves, and slight mod'ed cam. Now a single carb, but I planned to maybe go to a 2x2. Guess I'll see if the cam holds up. No valve flutter at 70mph.

[Ol' Ron]

The LZ spring is around 60. I have a 294 I built a few years back in a friends 38 PU/ Engine has an L-100, 9:1 Cr 3 97's and turns over 5K every time we go to lunch. 50/55 lbs on the cam. I have been doing this for the paast 20 years on street engine, Haven't had a valve float yet.

[flatjack9]

I don't think that the LZ springs are anywhere near 85 lb at the installed height. I use these quite often, but I would have to check my notes on the heights and pressure. I rarely go over 55 lbs on the seat.

[freddie]

I am by no means an oil "expert" but would like to share and pose a question or two:
I work with very large generators of which runs on white metal bearings similar to those used in our cars. The shaft that sits in the bearing has a diameter of 1' 9" and the bearing length is 2' 6". These bearings were manufactured late 40's early 50's. The rotor which is supported by two bearings weigh 68 metric tons.

The bearings have a top and bottom also similar to those used in our cars. With the generator rotor in position we remove the top half of the bearings and pour normal Wynns (an oil additive) oil on the shaft. Plus minus 3 cups of oil. We also do the same with the bottom half of the bearing prior to setting the rotor into it. I can then turn this shaft of 68 tons with my hand. When in operation this rotor will run at 3000rpm 24/7 for 6 months and longer and we only open the bearings for inspection every 6 - 7 years.

Can someone please explain to me what the function of zink is or was in the oil?

We use normal Castrol GTX (Ashless) oil on this lubrication system and the sump hold 9500 gallons of oil.

Thanks

[Pete]

Originally Posted by freddie

I am by no means an oil "expert" but would like to share and pose a question or two:
I work with very large generators of which runs on white metal bearings similar to those used in our cars. The shaft that sits in the bearing has a diameter of 1' 9" and the bearing length is 2' 6". These bearings were manufactured late 40's early 50's. The rotor which is supported by two bearings weigh 68 metric tons.

The bearings have a top and bottom also similar to those used in our cars. With the generator rotor in position we remove the top half of the bearings and pour normal Wynns (an oil additive) oil on the shaft. Plus minus 3 cups of oil. We also do the same with the bottom half of the bearing prior to setting the rotor into it. I can then turn this shaft of 68 tons with my hand. When in operation this rotor will run at 3000rpm 24/7 for 6 months and longer and we only open the bearings for inspection every 6 - 7 years.

Can someone please explain to me what the function of zink is or was in the oil?

We use normal Castrol GTX (Ashless) oil on this lubrication system and the sump hold 9500 gallons of oil.

Thanks

Zinc/Phosphorus is for hard metal bearing surfaces like cam shaft lobes, piston rings and valve guides.

[Tinker]

Originally Posted by Ol' Ron

The LZ spring is around 60. I have a 294 I built a few years back in a friends 38 PU/ Engine has an L-100, 9:1 Cr 3 97's and turns over 5K every time we go to lunch. 50/55 lbs on the cam. I have been doing this for the paast 20 years on street engine, Haven't had a valve float yet.

Good to know. Thank you.

[freddie]

Thanks Pete

[Talkwrench]

Its a wonder Lawrie hasn't come along. Im sure he said to me they ran valve springs of not much more than 50lbs on their drag rail and shifted at 5600- 5800rpm.
Correct me if Im wrong Lawrie ..

[Ol' Ron]

Here's agood one. I put a Max#1 cam in an engine and told the guy i had to change the valve springs and keepers, because the engine had rotatos. He said why, I didn't really know. I put a .050" shim under the springs and off it went. Guess it worked it never came bacl. Now On the small engine I;m building for the roadster I;ll do the same. then we;ll see when the valves float.

[cmbrucew]

On that big generator the oil pump was started before the generator so the armiture was floating on oil . typical for ball mills and most large rotating machinery.
Bruce