Valve Spring Question Mark IV 454

[DSnyde34]

Hello everyone,

I have a Mark IV 454 in a 74 K20, the motor needs a new camshaft. I have decided on putting the COMP Grind XE262H-10(11-238-3) and an Edelbrock Performer 2-0 Intake Manifold(2161) on the motor. I had someone tell me that I should just use the valve springs that are currently on it. After some research I think this is a bad idea and that I should go ahead and replace the valve springs. The two springs recommend by COMP for this camshaft are part #s 911-16 and 924-16. With that I know virtually nothing about this stuff so, should I get single or dual springs? What do I need to get besides the springs themselves Valve seals, Locks, Retainers etc. What do I need to get new and what can I reuse. Also will new springs mean that I also need new push rods and rocker arms? And lastly I have seen a lot of information on camshaft break in and valve spring break in but hardly anything on breaking them in at the same time. Any tips on break in procedure for new springs and cam, is it possible to break them in at the same time or do I need to break in the camshaft on the old springs? Thank you in advance for the help as I said I know virtually nothing about this stuff so any information is appreciated.

 

[bluecamden85]

Not sure on cam and new springs but I recommend if u have umbrella seals to get all rubber. All I could find was hard plastic fel pro . Went to machine shop and they hook me up with all rubber. The originals were hard plastic and most were cracked with no top for valve guides.

 

[bucket]

Definitely replace the springs. The specifics all depend on which heads you have and if you are taking them to a machinist. You need to verify clearances and determine if you can use either of those recommended springs without machine work. If they don't fit and if you aren't going to a machinist, you'll need to find springs that have similar specs but fit in place of the stockers. Your spring retainers and locks will also need to jive.

If you have 5/16" pushrods, you will need to replace them with 3/8" pushrods and matching guideplates.

 

[Wumbo]

Run the single springs, and get a set of rotator eliminators too

 

[bucket]

Run the single springs, and get a set of rotator eliminators too

Yeah, I forgot about that. Definitely do that too. If your heads happen to have rotators on the intakes too, the eliminators may need opened up a bit to fit.

 

[AKguy]

Hello everyone,

I have a Mark IV 454 in a 74 K20, the motor needs a new camshaft. I have decided on putting the COMP Grind XE262H-10(11-238-3) and an Edelbrock Performer 2-0 Intake Manifold(2161) on the motor. I had someone tell me that I should just use the valve springs that are currently on it. After some research I think this is a bad idea and that I should go ahead and replace the valve springs. The two springs recommend by COMP for this camshaft are part #s 911-16 and 924-16. With that I know virtually nothing about this stuff so, should I get single or dual springs? What do I need to get besides the springs themselves Valve seals, Locks, Retainers etc. What do I need to get new and what can I reuse. Also will new springs mean that I also need new push rods and rocker arms? And lastly I have seen a lot of information on camshaft break in and valve spring break in but hardly anything on breaking them in at the same time. Any tips on break in procedure for new springs and cam, is it possible to break them in at the same time or do I need to break in the camshaft on the old springs? Thank you in advance for the help as I said I know virtually nothing about this stuff so any information is appreciated.

Call the folks at Comp, they will set you straight. They have always been very patient with me.

 

[Craig Nedrow]

The 924 springs are great for a moderate life cam, but are somewhat heavy @ 175 gr for the spring and retainer. Compare that to comp cams # 26918 beehive and hardened steel retainer @ 125 grams. This combo will give you up to .66 lift. 125 seat pressure and 367 open lbs. PAC springs # 1220 are high quality and very similar to the above data. Springs are a very big deal, worth hp and more rpm. Also you might consider buying a adj push rod to get the length right, then buy 3/8 .080 wall pushrods. Heads and optimal valve train are worth tons of power for about the same money as a ok setup.

 

[Craig Nedrow]

Mark Jones is a member here, and builds these motors, and has proven results.