Really Stupid Question
Thread Starter
Instructor
Joined: Jul 2008
Posts: 123
Likes: 0
From: Wertheim Baden-Württemberg Germany
Really Stupid Question
Hi All,
Am in the process of putting my 350 heads back together after a valve job.
Have a new cam kit from Comp,with lifters,springs ,retainers,ect.
Noticed that the Comp retainers are all the same.No collars,no exhaust rotaters,no nothing,just the retainers and keepers.
Question is,should I use the new retainers as they are,or would I be better off using my old stuff with the new springs?
When I measure the valve lengths I see that the exhaust valve is a bit longer than the intake valve.The difference I believe is evened out by the original retainers, as the exhaust retainers ,with rotaters, are taller than the intakes.If I just slapped the Comp retainers on ,could this cause 2 different seat preasures.
I sent this same question to Comp,but recieved no answer.
Any Ideas?
Alan
Am in the process of putting my 350 heads back together after a valve job.
Have a new cam kit from Comp,with lifters,springs ,retainers,ect.
Noticed that the Comp retainers are all the same.No collars,no exhaust rotaters,no nothing,just the retainers and keepers.
Question is,should I use the new retainers as they are,or would I be better off using my old stuff with the new springs?
When I measure the valve lengths I see that the exhaust valve is a bit longer than the intake valve.The difference I believe is evened out by the original retainers, as the exhaust retainers ,with rotaters, are taller than the intakes.If I just slapped the Comp retainers on ,could this cause 2 different seat preasures.
I sent this same question to Comp,but recieved no answer.
Any Ideas?
Alan
Melting Slicks
Joined: Dec 2009
Posts: 3,235
Likes: 658
From: Thunder Bay
Not a stupid question at all. I've built several of these motors, but I'm not sure how to answer your question. The rotators were there as I understand it, to rotate the exhaust valves to keep heat from building up and burning the valves after they took the lead out of the gas. The lead would lubricate the valves and prevent them from burning. Now they use hardened seats which appears to accomplish the same thing. It seems to me you have to either install the rotators with the new springs, or shim the valve springs to make up for the thickness of the rotators. Either way you need to have the correct installed height/pressure in the springs. Hopefully we will hear from someone with a little more experience. I'm interested in the answer to this one.
Thread Starter
Instructor
Joined: Jul 2008
Posts: 123
Likes: 0
From: Wertheim Baden-Württemberg Germany
Did find one note though in the "common mistakes" section.
"For most engines using a 268H or larger cam you MUST change the valvesprings and if necessary
remove the exhaust valve rotators to achieve the correct height and spring pressure".
Also this statement "COMP cams strongly recommends replacing valve springs on any engine with 60,000 miles
or more.Stock (O.E.M) springs may be retained in some applications where a small camis used such as 252H or 260H"
I have a 262H kit.Still up in the air as what to do.
Last edited by Ravoll; Dec 29, 2011 at 11:40 AM.
