Comp Cam 918 Springs Question
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12
Comp Cam 918 Springs Question
I am going Forced Induction soon and want to swap my factory springs with Comp cam 918 springs as added insurance to avoid valve float.
Car is a 2000 C5 with stock heads/cam and 60k miles. I have just bought some brand new Comp Cam 918 Springs only. Do I need brand new locks, lock retainers, retainers, seats, exhaust valve and intake valve seals to swap my old springs with the new 918 ones?
If so, where can I find these items as a complete kit. How many of each do I need of each item including spares? Does it matter if I buy GM parts or aftermarket ones?
I already have access to spring swap tool. Anything else I need besides a compressor?
Any help would be greatly appreciated.
Car is a 2000 C5 with stock heads/cam and 60k miles. I have just bought some brand new Comp Cam 918 Springs only. Do I need brand new locks, lock retainers, retainers, seats, exhaust valve and intake valve seals to swap my old springs with the new 918 ones?
If so, where can I find these items as a complete kit. How many of each do I need of each item including spares? Does it matter if I buy GM parts or aftermarket ones?
I already have access to spring swap tool. Anything else I need besides a compressor?
Any help would be greatly appreciated.
Team Owner
Joined: Mar 1999
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From: At the beach in little Rhody
No, retainers/locks/etc. will all fit.
However, while its apart it is really a good idea to measure your installed height and shim so you have the same seat pressure on all springs. I tested some 918's last winter with a digital load cell from work and found they were extremely consistant between springs. I also prefer the machined locks over the stamped OEM's, but that is just me being cautious. With that many miles on the car, and the fact that they are right there, I personally would also swap in a new set of seals but again that is personal preference. So you can swap in the springs directly, but as options you can consider new seals and machined locks (other opinions will be different on this I am sure). I would measure your installed height with a spring micrometer too.
However, while its apart it is really a good idea to measure your installed height and shim so you have the same seat pressure on all springs. I tested some 918's last winter with a digital load cell from work and found they were extremely consistant between springs. I also prefer the machined locks over the stamped OEM's, but that is just me being cautious. With that many miles on the car, and the fact that they are right there, I personally would also swap in a new set of seals but again that is personal preference. So you can swap in the springs directly, but as options you can consider new seals and machined locks (other opinions will be different on this I am sure). I would measure your installed height with a spring micrometer too.
Melting Slicks
Joined: Aug 1999
Posts: 3,452
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From: Spring, TX
You can re-use the factory locks and retainers. However I agree with Vettenuts. I would use new machined retainers from Comp as well. You can still use the factory locks. I would recommend that you buy one bag of extra locks from a local dealer you can get them when you pick-up your new valve seals as they should be changed with your milage. Cheap insurance. You need the extra locks because the little bastards have a tendancy to go flying and disappear. Don't want to be held up by one missing tiny piece of metal.
Changing the seals is easy. Us needle nosed plier to pull off the old seals. Be careful not to hit the valve with the teeth of the pliers. Scratches are no good. Push the new seals on with your fingers and the use a deep socket that is slightly smaller than the seal to push down over the valve to make sure the seal is seated. You will hear a faint click and feel it as well. An improperly seated seal will leak a lot of oil so make sure it is seated but don't crush it either.
Changing the seals is easy. Us needle nosed plier to pull off the old seals. Be careful not to hit the valve with the teeth of the pliers. Scratches are no good. Push the new seals on with your fingers and the use a deep socket that is slightly smaller than the seal to push down over the valve to make sure the seal is seated. You will hear a faint click and feel it as well. An improperly seated seal will leak a lot of oil so make sure it is seated but don't crush it either.
Melting Slicks
Joined: Jan 2003
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Likes: 4
great advice above.
*new valve stem seals
*a few extra locks because you always drop one or two
*Vaseline, dab each lock with it and they'll stick to the stem(highly recommend)
*a pen magnet(as you compress the spring stick the magnet on the locks)
*air compressor adapter to fill the cylinder
*No need to by new retainer or seat the 918s are direct drop-in
you want the least pressure you can get away with. I run 9-10# and the 918s work flawlessly. More is not better with valve springs especially on the stock heads. Too much pressure will stress the heads and valvetrain. Besides it will cause extra drag that will cost you hp.
*new valve stem seals
*a few extra locks because you always drop one or two
*Vaseline, dab each lock with it and they'll stick to the stem(highly recommend)
*a pen magnet(as you compress the spring stick the magnet on the locks)
*air compressor adapter to fill the cylinder
*No need to by new retainer or seat the 918s are direct drop-in
you want the least pressure you can get away with. I run 9-10# and the 918s work flawlessly. More is not better with valve springs especially on the stock heads. Too much pressure will stress the heads and valvetrain. Besides it will cause extra drag that will cost you hp.
Last edited by IM QUIKR; Nov 22, 2006 at 12:07 PM.
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Originally Posted by gonbad
You can re-use the factory locks and retainers. However I agree with Vettenuts. I would use new machined retainers from Comp as well. You can still use the factory locks. I would recommend that you buy one bag of extra locks from a local dealer you can get them when you pick-up your new valve seals as they should be changed with your milage. Cheap insurance. You need the extra locks because the little bastards have a tendancy to go flying and disappear. Don't want to be held up by one missing tiny piece of metal.
Changing the seals is easy. Us needle nosed plier to pull off the old seals. Be careful not to hit the valve with the teeth of the pliers. Scratches are no good. Push the new seals on with your fingers and the use a deep socket that is slightly smaller than the seal to push down over the valve to make sure the seal is seated. You will hear a faint click and feel it as well. An improperly seated seal will leak a lot of oil so make sure it is seated but don't crush it either.
Changing the seals is easy. Us needle nosed plier to pull off the old seals. Be careful not to hit the valve with the teeth of the pliers. Scratches are no good. Push the new seals on with your fingers and the use a deep socket that is slightly smaller than the seal to push down over the valve to make sure the seal is seated. You will hear a faint click and feel it as well. An improperly seated seal will leak a lot of oil so make sure it is seated but don't crush it either.
I think I used a 12mm deep 6 point (1/4" drive) socket to push my new seals down on to the head. Worked perfectly. Just eyeball the installed position on the old seals as a guide to how far down the new ones go. Piece of cake.I picked up my air line adapter for the spark plug holes from NAPA. Cheap too.
HTH,
Robert
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From: At the beach in little Rhody
Originally Posted by gonbad
You can re-use the factory locks and retainers. However I agree with Vettenuts. I would use new machined retainers from Comp as well. You can still use the factory locks.
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12
on the machined locks and retainers.Cant I just use the OEM GM ones or is it a wise idea to go with the machined ones? Anyone's got a link to the complete kit that I need without springs?
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Originally Posted by FactoryRaceCar
on the machined locks and retainers.Cant I just use the OEM GM ones or is it a wise idea to go with the machined ones? Anyone's got a link to the complete kit that I need without springs?
Check Comps website for the hardware items you need and get part numbers, then find a vendor. Thunder Racing did me good on pricing.
HTH,
Robert
Team Owner
Joined: Mar 1999
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From: At the beach in little Rhody
While I agree on the retainers, I am nervous about recommending them now since someone had problems installing them as they were overly tight and the springs ended up breaking. That is the only instance I have heard of this. The Comp retainers should fit better though.
Springs/Retainers
Valve Locks: 623-16
Retainers: 774 - Steel, 772 - Titanium
Springs/Retainers
Valve Locks: 623-16
Retainers: 774 - Steel, 772 - Titanium
Last edited by vettenuts; Nov 22, 2006 at 08:42 PM.
Racer
Joined: Mar 2006
Posts: 464
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From: silverdale washington
I would not buy ti locks, waste of money, If youre going to buy ti, buy retainers but not required. Also I would order to sets of locks when you order. Crane usually includes 32 + 1 extra and comp usually only 32. Howver I have done 2 builds in last month and both crane and comp sent me locks with the wrong machining on 2 locks!!! That will really **** you off and its always the last one when you think you are done. When you are done take a flashlight and look around the edge of where valve stem and lock meet and make sure the lock touches the valve stem all the way around not just on the outside corners. These parts are about $1 a piece and if they are wrong it could cost you a motor.
Burning Brakes
Joined: Aug 2006
Posts: 789
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From: Shreveport LA
Originally Posted by TYSON1997
Howver I have done 2 builds in last month and both crane and comp sent me locks with the wrong machining on 2 locks!!! That will really **** you off and its always the last one when you think you are done. When you are done take a flashlight and look around the edge of where valve stem and lock meet and make sure the lock touches the valve stem all the way around not just on the outside corners. These parts are about $1 a piece and if they are wrong it could cost you a motor.
Thread Starter
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12
So guys basically you are saying that I dont need any new hardware (stock or aftermarket) to go with my new 918 springs and I can use the existing hardware without any problems. Correct?
I can get new oem GM hardware but not required and I do it only if I want to do it?
I can get new oem GM hardware but not required and I do it only if I want to do it?
Melting Slicks
Joined: May 2005
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From: Leon Iowa
St. Jude Donor '06-'07-'08-'09
Originally Posted by FactoryRaceCar
So guys basically you are saying that I dont need any new hardware (stock or aftermarket) to go with my new 918 springs and I can use the existing hardware without any problems. Correct?
I can get new oem GM hardware but not required and I do it only if I want to do it?
I can get new oem GM hardware but not required and I do it only if I want to do it?
Thread Starter
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12
Originally Posted by mvvette97
yep
BTW Marc, buddy has the spring swap tool so I think I should be ok.
Melting Slicks
Joined: May 2005
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From: Leon Iowa
St. Jude Donor '06-'07-'08-'09
Originally Posted by FactoryRaceCar
As long as none of the locks or retainers or anything go flying away
BTW Marc, buddy has the spring swap tool so I think I should be ok.
BTW Marc, buddy has the spring swap tool so I think I should be ok.
Thread Starter
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12
Originally Posted by mvvette97
Does he have the Crane or the Moore tool? I can change the springs on my TA in about 1 1/2 hrs with the crane tool. I like it because you can do two springs at one time. I also always use the top dead center method. The air thing I don't trust because a buddy of mine has a valve fall because thew air hose sprung a leak. the TDC method eliminates all chances of a valve falling.
Maybe we can swap the springs and install the boost and fuel pressure gauges too
Last edited by FactoryRaceCar; Nov 23, 2006 at 02:05 AM.
Melting Slicks
Joined: May 2005
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From: Leon Iowa
St. Jude Donor '06-'07-'08-'09
Originally Posted by FactoryRaceCar
I dont know which one he has but I know that I can drive 2 hours to borrow yours
