Camshaft wiping lobes

[2FAST4U]

I'm beginning to tear down a 60-65K mile longblock that I got out of a local wrecked GN. While tearing apart, I found that the #3 exhaust lobe is partially wiped. I will be rebuilding this engine, basically a re-ring and re-bearing job because everything still checks out good. Of course, I will be installing a new cam and this is where I have questions. Unfortunately, a roller cam is not in the budget. I will be installing either the 204/214, Comp 206 (Weber), or something else comparable. Since this block has wiped a cam before, is there anything that I can do to help prevent excessive wear on the new rebuild? Everything is apart so now is the time to do anything helpful.

The alternatives that come to mind are:
1) break in the new cam/lifter as normal (not much one to HOPE it doesn't wipe)
2) cryogenic treatment of the cam and lifters to harden both surfaces.
3) use either the "cam saver" or "cool face" lifters to help oil the cam better
4) bush the lifter somehow to help the alignment over the cam lobe.

Please give me some opinions and any other ideas that will help.

 

[Slow91z]

Get some weaker springs for the break in...of course don't take it upstairs with the weak springs in...after a proper break in change to the good springs.

 

[2FAST4U]

Thanks, I was planning on the weaker springs too. Anybody ever heard of doing anything to the lifter bore to help this?

 

[Slow91z]

Actually, now that you mention it, I have heard somewhere something about lifter bores going out of round or something to that affect...I'm pretty sure it was about small block chevy's but it could apply here.

 

[Lee Thompson]

coating

Calico Coating in NC can moly coat you cam for around $40. 90 psi max. closed spring pressure will go a long way to making it live.

 

[2FAST4U]

Both the coating and cryogenic treatments are around the same price. I wondering if there is any difference between the two.

I figure that I will install a new set of the old faithful Comp980 springs. They've been proven plenty of times.

 

[Two Lane]

Briefly, the cryo tx "hardens" the metal. The coating puts an anti-friction layer upon the surface.

With the damage possible from a wiped cam, it's still wayyy
cheap-enough to do both.

Tell us about the special lifter treatments you mentioned.

TIA!!

 

[2FAST4U]

I had heard of both the "Cam Saver" and "Cool Face" lifters before, but have not used them myself. After some searching, I found that both are made by Crower. The "Cool Face" lifter is actually for a solid lifter, so it is not applicable. The Cam Saver lifter does look helpful. According to their catalog, they have machined flats on the side of the lifter to provide an additional 12-16 ounces of oil per minute to the cam lobe without adversely affecting engine oild pressure (nominal 1-2 # drop). The part nuber that they list for the Buick Evenfire 78-up is 66050X3-12. I don't have a price on these, but will probably try them out unless someone here has had any bad experiences with them.

 

[87GN_70GS]

I vote for #4. Lifter bore correction is done quite often in those engines that need it.

 

[Two Lane]

Originally posted by 2FAST4U


The Cam Saver lifter does look helpful.

According to their catalog, they have machined flats on the side of the lifter to provide an additional 12-16 ounces of oil per minute to the cam lobe without adversely affecting engine oild pressure (nominal 1-2 # drop).

The part nuber that they list for the Buick Evenfire 78-up is 66050X3-12.

I don't have a price on these, but will probably try them out unless someone here has had any bad experiences with them.

***********************************************
Why not start a brand new thread to ask if anyone has used them?
***********************************************
They sound great!

Thanks for the info!!

 

[Two Lane]

Originally posted by 87GN_70GS


Lifter bore correction is done quite often in those engines that need it.

Have any idea how much that costs?

Sounds as if only one of the lifter bores is "offset", needing correction.

TIA!!

 

[jastrckl]

#3 exhaust, IIRC.
HTH.

 

[GNandTTA]

#3 exhaust was bad on mine as well. So I tapped off the oil supply and ran a dedicated line right to the lobe. Oil will splash on that lobe all the time.

 

[jastrckl]

As I understand it, the issue is that our #3 exhaust lifter bore is "too centered" over the cam lobe and thus doesn't always spin as it should, so it wears in only one spot. Adding an oil line is good I bet but still doesn't really address the problem. Bushing the lifter bore to get the lifter to spin again just like the other lifters should make everything gravy, but it's more expensive.

 

[1badTTA]

As someone mentioned earlier about using soft springs, they are wrong. I have managed to wipe out a lobe on an aftermarket cam (not mentioning names) and I feel it is most likely due to the soft factory springs I had in the car. After 500 miles I replaced the springs and still managed to wipe the cam in 2,000 miles (#1 exhaust lobe). I installed the factory cam with new lifters and it has ran fine for the last 13,000 miles after that.

Moral of the story, if the valves float once you may have just wiped your new cam.

 

[Slow91z]

Excuse me, I said to use softer springs for the BREAK-IN...not for everday.

 

[2FAST4U]

Originally posted by 87GN_70GS
I vote for #4. Lifter bore correction is done quite often in those engines that need it.

Any details on doing this, like specs on how far the bore is offset and which way? This could vary between blocks, but what would you measure to get a starting point and what lifter bore position are you trying to achieve?

Any ideas on what this would cost?

 

[87GN_70GS]

Not sure on cost but should be reasonable. Of course it will vary depending on which machine shop you talk to.

0.060" - 0.080" should do it, If I recall correctly, it needs to be moved towards the front.

 

[KendallF]

Originally posted by 87GN_70GS
Not sure on cost but should be reasonable. Of course it will vary depending on which machine shop you talk to.

0.060" - 0.080" should do it, If I recall correctly, it needs to be moved towards the front.

BHJ makes a fixture to correct spacing and angles for the lifter bores. The fixture retails for $1800 and it requires a dedicated fixture kit for each block (i.e., SBC, Buick V6, BBC, etc.).
They are bored, bushings inserted, and the bushings are honed for correct lifter fit. I have watched a SBC being done and it's a pain..the charge is somewhere north of $200 here.

Doing just one lifter bore on a mill would probably be more reasonable but still would be a pain to set up.

 

[Two Lane]

Originally posted by jastrckl


Bushing the lifter bore to get the lifter to spin again just like the other lifters should make everything gravy, but it's more expensive.

Do you know of a particular engine builder or machine shop that is set up to do this on the 109 blocks, i.e., someone who has done this before?

TIA!!