flat tappet cams and friction coatings

[BOWTIE6872]

now for the last 8 years the flat tappet cam and oil without zinc issue has been around with tons of different oils/ add and ways to break in the cam.
light springs/ no proload/etc

why not just coat the cam lobes with a friction coating and let it slowly ware off and ware in the cam/lifter together..
seems to easy, am I missing something

[Huskinhano]

Re: flat tappet cams and friction coatings

If I'm not mistaken, Comp Cams has a hardening treatment, of course at an added cost on some cams.

I'm still out on the debate. There's a lot of factors that need to be looked at before you rule on the zinc thing IMO. There are faster ramps, stiffer springs and for a while off shore "quality" tappets. I wonder if these factors added to the perfect storm. In the mid 70's I worked the parts counter at a Chevy dealer. I saw a lot of wiped cams and sold an awful lot of cam & tappets!

[SpiderGearsMan]

Re: flat tappet cams and friction coatings

it is a tuftriding treatment
I say go roller

[BOWTIE6872]

Re: flat tappet cams and friction coatings

I roller everything now..
cost to much not to..
one lube fails and the money saved not going roller just left the building

[min301]

Re: flat tappet cams and friction coatings

It was Crane Cams Mikronite process.

[BOWTIE6872]

Re: flat tappet cams and friction coatings

what was..
?
i was talking like the coating they put on piston skirts

[min301]

Re: flat tappet cams and friction coatings

If I'm not mistaken, Comp Cams has a hardening treatment, of course at an added cost on some cams.

I'm still out on the debate. There's a lot of factors that need to be looked at before you rule on the zinc thing IMO. There are faster ramps, stiffer springs and for a while off shore "quality" tappets. I wonder if these factors added to the perfect storm. In the mid 70's I worked the parts counter at a Chevy dealer. I saw a lot of wiped cams and sold an awful lot of cam & tappets!

I was reffering to this post.

[Caveman]

Re: flat tappet cams and friction coatings

I think the piston skirt coating stuff is a teflon... which in a wiping-action scenario (like a lobe-to-lifter)would maybe start to come off like the coating on your frying pan when you make scrambled eggs with a metal fork.

I think a lot of the flat tappet problem stems from the fact that if you harden one item, (cam), but not the other, then you have two items of different hardness in constant contact;

Harder metal always wins.


Proper break-in ensures that BOTH the cam lobe surface and the lifter surface harden to the same level.
The heat cycles they go through are what does it...

Same reason rusty exhaust bolts are hard to cut through... they've been friggin' heat treated.

[Scott Liggett]

Re: flat tappet cams and friction coatings

If I'm not mistaken, Comp Cams has a hardening treatment, of course at an added cost on some cams.

I'm still out on the debate. There's a lot of factors that need to be looked at before you rule on the zinc thing IMO. There are faster ramps, stiffer springs and for a while off shore "quality" tappets. I wonder if these factors added to the perfect storm. In the mid 70's I worked the parts counter at a Chevy dealer. I saw a lot of wiped cams and sold an awful lot of cam & tappets!

I was reffering to this post.

Yet most of those cams wiped, then and now, are from user error more than anything else.

[SpiderGearsMan]

Re: flat tappet cams and friction coatings

my blazer had an L98 GM roller , my nova had an ultradyne roller
the last 2 cars I put flat tappets in was richie's 57 in 1988 - still running good and his merc in 1995
still good
competition cams were pretty good
one of theories on the 80s gm cams was one plant getting the tooling wrong and the angle was death to the cam
all the 200 -229 v6 wrecked the cams
what a good paying job , but it helped import sales too much

[BBR]

Re: flat tappet cams and friction coatings

I roller everything now..
cost to much not to..
one lube fails and the money saved not going roller just left the building

Solid roller lifters fail almost as often as ft's from what I see...

[HEMI]

Re: flat tappet cams and friction coatings

The choice of engine was not mentioned.Maybe it's a Hudson Hornet 6 cyl.
Roller lifters?Ferget it.Maybe coating the cam would work,esp.if it's being reused.

[milner351]

Re: flat tappet cams and friction coatings

In a previous post I thought I heard mention of a lifter that had a hole on the cam face - it was EDM'd and was a very small hole like .008" or something - but it insured a pressurized flow of oil directly to the cam / lifter interface.

I am slowly building a Ford FE engine - talk about something that's expensive to go roller on! yowza!

so - I'm VERY interested in anything new that can put this issue to rest...

The other part of this issue I rarely hear discussed is the lifter / bore clearance....
it seems this part of the block machining process is rarely paid attention to.
I've heard of some folks enlarging the lifter bores and running bronze sleeves so they can run a larger diameter lifter that will put up with higher ramp lift rate cams, but beyond that, it seems that lifter bore clearance is mostly assumed to be correct and not really thought about much ???

However -- if a lifter stops rotating in the bore --- that's going to cause a problem and quick.

What was the lifter bore clearance on the first forum 454 with the flat tappet cam that killed itself during Seth's trip to NC ???

Is it junk metallurgy in the cams or in the lifters?
lack of zn/ph in the oil?
too much spring pressure?
too aggressive a cam profile?
- or too tight clearance between the lifter and the block?
all of the above?
a combination of these and more?

and

why is it that engines that have flat tappets and have been running for years are fine with the new oil?
it seems that just new flat tappet cam lifter combos that seem to have the problem? ???

[BOWTIE6872]

Re: flat tappet cams and friction coatings

I understand most times it's user error, but if a coating , lowers that to nil..
it's makes your product "look" better, cause , nothing can stop a guy from badmouthing a comp. even if it was their own fault..