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Valve spring issues

svshaw82

NAXJA Forum User
Location
Escondido CA
Hey guys, got myself into a bit of a snag.

First off, I bought myself the Comp Cams 68-232-4 camshaft. Then since I found out Comp doesnt have matching springs that fit out 4.0 head, I found on jeepforum.com an article that someone had said they were running the same cam with a set of Sealed Power SLP-VS-1456 springs.

They were affordable for me so I bought a set. Now that my cam finally came, I started looking into assembly. Saw a spec on the springs that shows installed Height 1.815 in, and Open Height 1.500 in. That only gives me .315 in lift, and the cam I have is .476 in lift!

Can any tell me where I can find a set of springs that will work for this cam, without breaking my bank? Thanks in advance!
 
mopar performance P5249464 at like $10 each.

otherwise you're going to need to machien the head to run a modern chevy beehive spring.

If you don't take up *too* much of his day without buying from him, Russ @ Bishop-Buehl will probably be more than happy to go over the jeep valve spring options with you. He's tried every combination possible.

Russ Pottenger
Bishop-Buehl Racing Engines
Work (626) 967-1000
Fax (626) 967-7836
Cell (626) 673-2203
 
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What year engine are you working with? maybe this will help answer some questions:
Free Height - is the overall height of the spring in an unloaded condition, when the spring is sitting on the workbench.
Solid Height - is the overall height of the spring in a fully compressed condition, when every coil is touching an adjacent coils, above and below.
Installed Height - is the overall height of the spring in a loaded condition, when the spring is installed on the cylinder head.
Coil Bind - is the difference between installed height and solid height. The rule of thumb is, the maximum valve lift should never exceed the Coil Bind minus 10 percent, or a minimum of .050 (fifty thousands).
Open Height - is the overall height of an installed spring, when the valve is in a fully open position.
Seat/Closed Pressure - is the specified load on a spring, when the valve is in a fully closed position, measured in lbs per square inch.
Nose/Open Pressure - is the specified load on a spring, when the valve is in a fully open position, measured in lbs per square inch. Note - the spring should be replaced if the pressure is less than 10% of the advertised Open Pressure.
Spring Rate - is the amount of weight required to compress the spring by one inch, rated in lbs/sq.in. (not to be confused with Spring Rating - see below).
Spring Rating - specifies load when fully closed (Seat Pressure) and fully open (Nose Pressure), may be a range or a specific number. Example: 80-85/160-165 or 80/160.
 
They were affordable for me so I bought a set. Now that my cam finally came, I started looking into assembly. Saw a spec on the springs that shows installed Height 1.815 in, and Open Height 1.500 in. That only gives me .315 in lift, and the cam I have is .476 in lift!
those specs don't tell you much. Open height does not mean bind height. You need specs like bind height, seal load, open load, etc.

Take a look at engle 593

x2
 
Per Summit Racing, the specs of the springs I bought VS-1456

Number of Springs Per Valve:Single
Outside Diameter of Outer Spring (in):1.315 in.
Coil Bind Height (in):1.130 in.
Damper Spring Included:No
Inside Diameter of Outer Spring (in):0.961 in.
Valve Spring Style:Standard

Installed Height (in):1.815 in.
Seat Pressure at Installed Height (lbs):46 lbs.
Open Height (in):1.500 in.
Open Pressure (lbs):121.4 lbs.

Is this something that might still work for my application?
 
After what Talyn said, do I subtract Bind Height from Installed Height? Because that would give me .685" Thats enough to clear my .476" lift with .209" to spare. Was I freaking out over the wrong numbers? lol!
 
Those springs are awful light. Install seat load is 88# @ 1.64". Open seat load is 202# @ 1.164".

Just for reference a stock spring load is 71# - 79# @ 1.64". Open load is 202#- 218# @ 1.216".

The install height for the 4.0L head is not 1.815". Its 1.64". You have .51" before bind closed & .034" open. Quite close.

These springs are marginally better than stock. I would not run them on any performance cam.
 
Those springs are awful light. Install seat load is 88# @ 1.64". Open seat load is 202# @ 1.164".

Just for reference a stock spring load is 71# - 79# @ 1.64". Open load is 202#- 218# @ 1.216".

The install height for the 4.0L head is not 1.815". Its 1.64". You have .51" before bind closed & .034" open. Quite close.

These springs are marginally better than stock. I would not run them on any performance cam.

So you dont think those springs will be ok with my cam? Its not a high revving engine, I got a hold of Engle. He said their springs have the following specs...

Spring OD 1.440” ID is 1.075”
At 1.700” 115 seat 215 to 230 open at 450” to 500” lift
Bind Height is 550” to 600" lift
 
The spring rate looks to be ok on the Isky spring.

Assuming your running stock valves and installing them around 1.650 you will be
around 130 on the seat and 270 open. My only problem with this spring is dimensionally
it's not going to fit the spring pocket in the head very well.
Because these mildly built Jeep engines have more similarities to tractor engine than
NASCAR engine, you should be fine. Just make sure you have proper fitting retainers
and valve locks.

Most of us that are building the fancy shiny port 4.0 heads are using Chevy LS stuff, and cutting down and Re-machining the spring pockets.

Hope this helps.
 
The springs I have fit in perfectly. I think I will bolt it all together and spin the valve train around to see how it cycles. The spring ratings should be ok right?
 
The springs I have fit in perfectly. I think I will bolt it all together and spin the valve train around to see how it cycles. The spring ratings should be ok right?
These springs are marginally better than stock. I would not run them on any performance cam.
Just because they fit doesn't mean anything.
 
Tayln, Im stuck in a really low budget. Its taken me over a year to get where I am now in my rebuild. Im really hoping they will work, or Im out the money for buying them, and have to spend more to get something else.

You say you would not run them on any performance cam, but is there a slight chance they might work for me? Sorry if I keep digging at it, maybe Im beating a dead horse, just bummed out I jumped the gun so fast on my build. Getting punchy as I get close to finishing up ya know?
 
The problem is with that slight chance they might work, the failure mode is pretty catastrophic.

Cheaper to fix it now than fix it when it blows up.
 
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