Anyone here heard a non sewing machine sound from 918 on a mild cam?
Look at my specs.Could I get by with LS6 springs,I know lift might be pushing it ?

 

i would not run LS6 springs with that

 

Why not?
Thats a perfect spring for that cam
What spring do think should be used

 

918
not the LS6

 

Linginfelter runs the LS6 springs with the GT2-3,Its a .009 less lift

 

LS6 springs are spec'd to hold .570 lift. .579 would be over that.

 

I thought they normally have saftey built in other here have ran stock LS1/w hot cams what are they spec'd at?,sorry not trying to sound like an ***.I have a set of 918s just dont want the noise if I can avoid it.

 

Here is GT2-3

Intake
Exhaust

Lobe lift:
0.336"
0.340"

Rocker ratio:
1.7:1
1.7:1

Valve lift:
0.571"
0.578"



Duration at 0.050:
207°
220°

Advertised (total) duration:"
255°
281°



Lobe separation angle:
118.5

Centerline:
118.5

I was mistaken,there is only .001 difference lift between cams,do you trust there company that they know what they are doing when selling that cam with those springs?

 

I would not run LS6 springs with either. Especially with a single spring where if the spring breaks it will drop a valve and you'll have bigger problems in your hands. With Double Springs I would feel safer using them close to their maximun specified lift but even then I would not go over. My .02

No unless they are willing to put in writing that if I brake a spring they will cover all the damages to the cam and motor.

 

my understanding of what I've read here is that the short duration large ramp camshafts seem to upset the valvesprings more than the smoother ramps of more duration and lift. yeah Most companies spec in a .050 safety margin. but sometimes they advertise on th cutting edge. Only way to know for sure is to have them measured and as hard as I've looked noone has really gave a definite answer. I was thanking about using a CC 275 568 112 lc camshaft on these springs but have doubts.

 

i ran the gt2-3 and there was no way i was going to run stock ls6 springs when i have seen people break them on stock cams.The 918 is 100 times better then the ls6 spring as far as durability and valve control..The 918's that i ran with my gt2-3 were not quiet either..my duals are less noisy suprisingly.

 

Guys,
1- There is no such thing as a "noisy spring". The valvetrain noise is a result of improper preload on lifters due to the wrong pushrod length (or bad rocker adjustment if you are running adjustables)
2- yes you can run LS6 springs on that cam. You could run 03 "orange" LS6 or shimmed 02 (yellow)
3- IMO run your 918's but use 7.425 push rods. Your "noise" as you call it will be reduced.

 

Someone telling me what I want to hear.
No need to uses yellow and shim
7.425 is a custom length?
Would the "orange" have any chance of valve float shifting at 6200 with 6-7 Lbs boost?

I have a lot of faith in the orange springs because Linginfelter does,I have heard of more 918s breaking than Ls6,I am not saying they will handle more ,just that less reports of breakage on mild cams.Anyone feel free to tell me where I am wrong.

 

Now you are throwing boost in the mix. Then you should definately run 918's.
7.425 is not a custom length, Comp Cam makes them.
Comp makes p-rods in .025 increaments.

The 918's are THE best single beehive spring out there. I've ran 918's on .610 lifts for more than 20K miles before with no issues. Proper geometry and preload is necessary.

 

What he said.

 

I will take your word for it 918s,although linginfelter recommends the GT2-3 cam and LS6 spring PKG for the radix applications.If I toss in the 7.425s Will i have to chance of the preload being to tight?This new trucks valvetrain is whisper quiet,is the base circle smaller on this new cam over OE?

THANKS

ONE more question pros
Do you see anything wrong with this cam I plan on using ? Going Radix in this truck.

 

The Lingenfelter lobes are proprietary lobes and their ramp rate is considered lazy by todays market standards.
Boost will increase cylinder pressures tremendeously and require increased spring pressures capabilities.
if your springs do not have enough pressure potential, they will not close your valves on time and a hanging valve will result, therefore bleeding that valuable boost.

Aftermarket cams have smaller base circle than stock, therefore we need to compensate the decreased effective base radius with longer p-rods to re-establish close to or at stock preload. stock lifter preload is usualy around .100
I usualy shoot for .080 to .100 on stock lifters.

 

Please take a look at my last post,I added to it.THANKS

 

Any reason for shimming the yellow and not the orange? the sticky at the top list the seat pressure the same. Any Idea how large of a shim. I have a set of the LS6 springs already and am looking at a .568 lift cam. Thanks for your help also.

 

can't tell you the shim size but you should shim within .050 of coilbind value.
the orange is an improved yellow and can handle ~.580