stock 5.2 Magnum valve springs MAX LIFT

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Slantsix64

Slantsix64

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Hey guys wondering whats the max lift on a stock magnum head with 1.6 rockers trying to run up to .533 lift on those puppies heres the cam info

Lift: .507 / .533, Duration @ .050: 221 / 225, Centerline: 108, Mild idle, Street performance, Big low end torque, Should have 9.0:1+ compression & 1800+ stall converter.

 5.2L - 5.9L Magnum

Camshaft Type:
Hydraulic Roller
Basic RPM Range: 1200 to 5700
Valve Lift Intake:.507
Valve Lift Exhaust:.533
Duration Intake:274
Duration Exhaust:278
Duration at 050 Intake: 221
Duration at 050 Exhaust:225
Lobe Separation:112
Intake Centerline:108
 
More info just incase you guys ask 1968 Barracuda 4 speed 3.55 gears RPM Intake 600cfm Carb
 
The springs would not be my first area of concern. Retainer to guide clearance would be.
 
Just get the Hughes 1110 spring kit. Stock springs are weak as hell, not to mention the retainers will hit the guides somewhere before .500” lift.
 
macdrew77 said:
Just get the Hughes 1110 spring kit. Stock springs are weak as hell, not to mention the retainers will hit the guides somewhere before .500” lift.
Click to expand...
Are you sure? For fact? The reason I ask is because I forget stuff, but, the MP 360/380 crate engine has a cam lifting the valve to .513 (IIRC, which is the issue right now.... LOL!) and the heads are simply stock with upgraded springs and no mention from MP or anyone else about a modified head or trick spring set up like the Hughes engine’s spring kit.

I know this topic has been covered before. A good searching should turn up the answer to the OP and the readers.
 
Is that the lift with the 1.6 magnum rocker arm ratio or the 1.5 everything else ratio?
 
The Magnum cam was a Hyd. roller that is used with the OEM rockers @ 1.6.
 
The camshaft in the original post requires better springs. Use the Hughes kit with springs, retainers, and locks. It is well worth the little extra money.

Post #12 in the thread linked below is the measurements I got for retainer to guide clearance with stock heads, pistons, valves, and head gaskets.

The 380hp crate engine used different retainers and straight Mopar springs instead of the beehive style stock springs.

Oil consumption and ticking after cam swap?
 
Bobzilla said:
The camshaft in the original post requires better springs. Use the Hughes kit with springs, retainers, and locks. It is well worth the little extra money.

Post #12 in the thread linked below is the measurements I got for retainer to guide clearance with stock heads, pistons, valves, and head gaskets.

The 380hp crate engine used different retainers and straight Mopar springs instead of the beehive style stock springs.

Oil consumption and ticking after cam swap?
Click to expand...

That's good information. The only concern I'd have is, not all the heads are the same in that regard. Some might can stand .550 lift at the valve. I've read where some contact about .100" less. So it's always safe to check.
 
The consensus my research indicated was .520 before machine work to the guides.

Agree on changing springs.
 
looks like hughes is out of stock, might just put some
P4876062
springs on it with new retainer clips and call it day
 
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YY1 said:
The consensus my research indicated was .520 before machine work to the guides.

Agree on changing springs.
Click to expand...
Stock magnum springs are done at 5000 rpm. My mag has the 1110 springs also Hughes retainers 512 lift cam and .020 guide clearance. I did recently read that Hughes has retainers to solve this clearance problem if you cam is .533 lift you better make you have valve/piston clearance
 
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YY1 said:
The consensus my research indicated was .520 before machine work to the guides.

Agree on changing springs.
Click to expand...

It's critical enough that I wouldn't rely on a "consensus". I will be measuring. Thinking of the consequences of retainer to guide interference is enough for me not to rely on anyone or anything but my own information. I don't take any chances there.
 
Just to be clear, mine was measured with the Hughes spring and retainer package installed, and they do add a little extra installed height and clearance.
I forget what the clearance was on mine with stock springs and retainers.
 
Brooks James said:
Stock magnum springs are done at 5000 rpm. My mag has the 1110 springs also Hughes retainers 512 lift cam and .020 guide clearance. I did recently read that Hughes has retainers to solve this clearance problem if you cam is .533 lift you better make sure you have valve/piston clearance
Click to expand...
 
Bobzilla said:
Just to be clear, mine was measured with the Hughes spring and retainer package installed, and they do add a little extra installed height and clearance.
I forget what the clearance was on mine with stock springs and retainers.
Click to expand...
I spoke pertaining to stock spring/inst height. Cheers
 
Geezz no to the factory springs. Toss them quickly. I just keep max lift to .525 and nothing's close to contact. The gross lift means nothing.
 
These are what I'm using

68044 Valve Spring Set

COMP Cams 632-16 COMP Cams Super Valve Locks | Summit Racing

COMP Cams 740-16 Steel Retainers, 1.437-1.500 Inch, 10 Degree

Everything went together great!

I'll let you know once I get the motor in and running, but so far no spring bind or valve to piston issue in my 5.2 Mag. I put the head on with NO head gasket and used playdough with no valve to piston issues.

Using the Comp 1.6 Chevy Roller tip rockers, Comp guides and 5/16 to 3/8 Stud conversion
 
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Tsully said:
These are what I'm using

68044 Valve Spring Set

COMP Cams 630-16 Super Valve Locks, 10 Degree/1-Groove, 11/32, Set/32

COMP Cams 740-16 Steel Retainers, 1.437-1.500 Inch, 10 Degree

Everything went together great!

I'll let you know once I get the motor in and running, but so far no spring bind or valve to piston issue in my 5.2 Mag. I put the head on with NO head gasket and used playdough with no valve to piston issues.

Using the Comp 1.6 Chevy Roller tip rockers, Comp guides and 5/16 to 3/8 Stud conversion
Click to expand...
Can you elaborate on your combo? The 11/32" locks you listed won't work for stock Magnum valve stem diameters.
 
Slantsix64 said:
Hey guys wondering whats the max lift on a stock magnum head with 1.6 rockers trying to run up to .533 lift on those puppies heres the cam info

Lift: .507 / .533, Duration @ .050: 221 / 225, Centerline: 108, Mild idle, Street performance, Big low end torque, Should have 9.0:1+ compression & 1800+ stall converter.

 5.2L - 5.9L Magnum

Camshaft Type:
Hydraulic Roller
Basic RPM Range: 1200 to 5700
Valve Lift Intake:.507
Valve Lift Exhaust:.533
Duration Intake:274
Duration Exhaust:278
Duration at 050 Intake: 221
Duration at 050 Exhaust:225
Lobe Separation:112
Intake Centerline:108
Click to expand...

Just a FYI
Hughes sells a lock and retainer set that has more lock to stem seal clearance.
Those 1110 springs and that retainer and lock set is what I used with my .512 lift cam.
The lock to guide isn’t the issue.
Locks to stem seal is.
The retainers and locks are from the 2.2 V6 motor and give a bit more clearance, but if I remember correctly not enough for a .533 lift.
Hughes can tell you for sure, as I spoke with them to get the parts I got.
 
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