At a bit of a crossroads here, my engine decided to eat the cam today. I have rice sized metal at the small holes of the oil filter. This leads me to believe it's done. Just wanting some opinion these are my options IMO:

1)I have a spare complete long block here, 416 heads stock cam.
1A)swap in another Summit cam kit and run it.
1B)run the peanut cam as-is
1C)Swap on the ported 416es from my current engine.
1D)Swap on the L05s I have. I am wanting to go boosted eventually so this would lower the CR but I'm not objectionable to that.

2)I have an L03 short block here, with an L98 TPI 'vette cam in it. No heads on it now.
2A)Pull my ported 416es from the current engine and reinstall
2B)Put a set of L05 heads.

3)Shove another cam in my current engine and hope for the best, and/or pull a few caps and see what kind of junk actually made it down below.

The cam I had was at least from 07, and I got it NIB from a member here who I suspect sat on it for some time. That means it would have been right in the heart of the flat shoddy tappet lifter era. Should I even consider doing another FT cam again?

 

So you weren't using any ZDDP additive?
I have a friend running those Chinese lifters, and they're surviving just fine. He runs cheap 10W30, plus a new, full, bottle of EOS every 3000 miles or 3 months, whichever comes first.
ZDDP isn't just for "break-in", it MUST be in there ALL the time.
Well, now that you're here, go roller lifters, sleep better, and save money long-term.

 

Yeah it was zinc added. I take that as a vote to build the L03 short block then.

 

I was agonising over this for my cam swap last year, and the previous one back on 05. I encountered symptoms of both the shoddy cheap lifter 'era' (did it ever end?), and the zddp problem. IMO, it's just a question of money to go roller, the main cost being the retro lifters.

Parts over here cost about double US or more, cheapest lifters I could find were about $800 AUD, so I stayed FT. However, the price of the Howards lifters there in the US looks lower now, I would probably go that route.

 

Agreed, I too have learned this. Comp additive goes in every change.

 

On another interesting note I pulled some of the lifters. Based on what I can see there are a few shiny cam lobes, but no "bowled" lifters so far. The dist gear is definitely gone! It was a melanized one and I was using it with a Summit flat tappet kit. I didn't think they were supposed to eat them. Did I miss something here?

 

I can't see why this should have happened, I also hope someone can give us the correct explanation.

 

I can't seem to tell what your current setup is, you haven't really told us what cam it is, what the block is etc?
Yank your intake manifold (or have you?) and pull the pushrods and lifters. If the lifters and cam are fine, maybe you just toasted the dist gear. If so, get another normal stock on, and go to town. Let your oil filter pick up the trash and keep driving. Can't do any more harm now...

 

years back... I gave my perfectly fine running engine to my.. in-Law... he bought a summit
cam, lifter combo... I installed... with Moly break in lube.. they must have disgustingly SOFT cams... some lobes were gone and typical lifter concave wear....
I honestly would stay away... from there cams

PS of all the builds I have done... never had other cams do this....

 

??? yes it can the tiny particles... will be like a hydraulic file.. and destroy the bearings

 

I would hope he'd be installing an "oil filter", to pick up those particles? Grab a wix and sleep well.

 

Maybe your distributor gear is hardened for roller cams and you toasted the cam gear?

See if you can look at the cam gear, if its okay, get a new distributor gear and try to rock on with it.

 

Actually, now that I think about it, a wiped cam & lifters would HIGHLY LIKELY -- NOT create rize sized chunks of metal. That does sound like teeth on a gear came off. If they are gone on the distributor, I would want to shine a flashlight down there to check the condition of the cams teeth. Hopefully they're ok, and you're only needing a new distributor gear!

 

Already pulled the top end, I have a bad feeling on this one. Engine's coming out to investigate regardless if it goes back in or not. I'm not going to take chances on it.

My theory is that the thrust of the cam is off because it's a flat tappet cam and it flattened a buncha lobes. Cam thrust gets outa whack, causes the gear alignment to get off and chews the gear. Just a guess though.

 

flat cams don't use thrust plates, nor buttons. It's just the crown of the lifters, and the angled lobes, that pushes the cam back, by indirect valvespring pressure, against the rear "freeze plug" in the back end of the cam bore. If that had moved, then your ignition timing would have changed dramatically, if not instantly.
For the cam to walk forward, there would have to be a problem with all the lifters / lobes.

 

I'm curious about this - when you get a ft that has flatted all the lifters and presumably also lost the chamfer from the lobes, doensn't this basically put it in the same situation as a roller and suddenly require end-float control?

There is the oil pump pressure pushing the cam back in the block, does this completely suppress the cam's ability to walk forward?

Re dist gear - last cam change, mine was starting to get chewed up too. The cam drive gear was fine. I put it down to use of the cheapest Chinesium.

 

I think you're right. And I forgot about the oil pump. And I never heard of Chinesium, very funny!
I used to think the lifter bores were angled, but that can't be, since the '87-up blocks came with both types of lifters in them.

 

I thought your lifters looked good? You don't need to pull the engine to check that, just the intake manifold. I'd try that first.

 

Roller cams are ground from a steel billet while flat tappet cams are ground from a nodular iron casting. Unless an iron dist/oil pump drive gear is installed onto the billet cam, the roller cam's gear will not stand up against a hard steel dist gear. Bronze gears are available for this. Best route if running a roller cam is to spend the money for a good unit with iron drive gear. If you're running a flat tappet cam, you have a much longer list of issues to deal with.

 

That's if you're using a steel billet cam with a steel gear. Lots (maybe even most these days?) of street roller cams have iron gears pressed on for compatibility with stock distributor gears.

 

FT cam, Melonized GM gear that should work for either a tappet or a production roller cam. Called Summit Racing support and confirmed it should be ok. Have pulled out 3/8 of the lifters and they looked fine, I'm wondering about the cam blank now. I am also wondering if the pump was chewing up bits of junk in it that increased the torque loading on the dist gear. Then again I would have thought it would have sheared the roll pin first, but that would be what I'd get for thinking.

 

no update?

at least the cam is still good it looks like.