sabersaw30

iTrader: (10)

I have always been curious what would be to much spring for a cam.I have a 585 lift cam in my car know not sure what springs is on it bought the car used like this.What would be a good lift spring to go with on a 585 lift cam?What would happen if you put to much spring on it like a 700 lift spring?Basically trying to figure out how much is to much?Would rule of thumb be 100 over the lift of cam?

Whiteaw57

iTrader: (2)

the trick to this is getting the right spring pressure in the range your cam lives at. You dont want to put a spring in thats going to be 160lbs seat pressure and 400 lbs at your .700 lift (this is totally hypethetical). Basically youd only have about 275 to 300 lbs at open and thats not enough. A good .600 lift spring would be ideal for your case. comp 918, pac1218, or even a pac 1518 shimmed to the right height if you want the nitrided spring. Main thing is to get your spring shimmed to where it is near its advertised lift when the cam is fully open so that you have enough pressure in order to control the valve.

BIG_MIKE2005

iTrader: (116)

Just as a example I run the Patriot Gold Dual kit with my 224/224 .581/.581 114 cam, had a set for 80k miles without a single issue.

Whiteaw57

iTrader: (2)

a lot of dual spring kits are .650 rated. Me personally I have the lunati gold duals and ran into valve float issues with the heavier retainers at 6800 rpm. I needed to shim them a tad since my cam is only a .610 lift.

sabersaw30

iTrader: (10)

I kinda see what you are saying.I am fixing to put a set of heads on the car just wanting to put the right springs on.I am dumb on this one.

Whiteaw57

iTrader: (2)

well youll need to determine your lift, and the type of lobe you have on the cam. If its super aggressive youll need stronger springs. Your typical open psi on a street LS1 is 400lb open. Stock rockers don't like much more.

farmington

iTrader: (14)

Too many people over-spring their motors. Unneeded spring pressure just eats up hp and is also hard on the rest of the valvetrain. You only need a good beehive spring with that cam.

poltergeist 02

iTrader: (65)

Go with the pac 1518's. Done

SweetS10V8

iTrader: (4)

I agree... Id use a Comp 918 here.

sabersaw30

iTrader: (10)

Nope no 918.https://ls1tech.com/forums/generatio...omp-918-a.html

SweetS10V8

iTrader: (4)

I would bet Comp sells 10:1 of their 918s to others. I run them on my personal vehicles, and on almost every engine I build. They are a great spring. They keep great vavletrain control, Ive seen it on the Spintron many times vs. duals.

A.R. Shale Targa

iTrader: (2)

PSI Maxlife beehive.....ls1511ml

bwkmaro

i even use the comp 918 in the v6 industry for bigger cams its a great spring no issues ive ever heard of. but ive also heard very good things about PAC so....

PowellSixO

iTrader: (1)

When chosing valve springs you need to look at the information given for the valve springs and compare it to your cam. For example, I am going to use PAC 1218's with a Comp Cam 220/218 .581"/.562" 111 LSA.

1.800"(recommended valve intsalled height)-1.140"(coil bind spring height)=.660" (spring opperating range)

.660"(opperating range)-.581"(max cam lift)=.079"(distance left before coil bind)

.079"(distance left before coil bind)-.050"(recommended tolerance before coil bind)=.029"

So if my math is right these springs will safely handle this cam with .029" of tolerance.

Whiteaw57

iTrader: (2)

I would throw a .025 shim under the locator though and take the spring to its open pressure point specified my the manufacturer. I have .030" of my springs that I didnt shim for and ended up with some high rpm valve float

PowellSixO

iTrader: (1)

My thoughts too. If you subtract .029 from 1.800 you get 1.771". I would want the installed valve spring height to be somewhere between these 2 numbers. If I were above 1.800" then I wouldn't have the advertised 130lb seat pressure when the valves are closed, and would lead to valve float as you said. If I were under the 1.771" I could get coil bind. I think after I rebuild my heads I am going to shoot for 1.775-1.785" installed spring height. This will give me more closing force and keep me safe on coil bind.