Well, some of you may have been watching the RPM Air-Gap vs. Victor Jr. thread, and I just finished taking everything apart so the Air-Gap could be port matched tomorrow and installed.

Turns out that isn't going to happen. Upon disassembly I found out my Demon (#@!@) is again leaking fuel, and for some reason the #2 port is full of carbon and fuel deposits, the others are kind of clean with fuel deposits on the valves...

Ok so I pulled all the rocker arms and they all looked fine, pushrods checked out fine as well. I pulled the lifters (Comp 818-16) and they all looked GREAT! The wheels were in great shape and the rollers felt as smooth as butta'

I guess the fun stops there, I was checking out the cam lobes through the lifter bores and the #6 exhaust lifter wasn't looking the part...
All the other lobes looked good, but #6 looks like someone dug a ditch in the rollers path ~.030-.060" deep.

That roller lifter is in perfect shape, so I am assuming the cam is bad.
I am going to call Comp tomorrow and ask them what they will do about it (read: nothing?). I don't see how this could be anything other than the cam material. This is a Comp XR-280R with a tempered cast steel core, commonly known as their street roller cam.

I see Crane Billet in my future.

Looks like racing season may be over, I wanted to refresh the motor this fall so it looks like I am getting an early start. :'(

Who knows, I may go ballistic and have it done by the weekend..

Stay Tuned.

EDIT UPDATE: Here is a picture of the TWO bad lobes, and there are more pictures below.

 

I feel lucky I have a Crower solid roller! Put up a pic if you get a chance, please...Wow...wazzup with all the Comp Cam failures?

 

Man I hate to hear that...but it's pretty common on the cast street rollers. I got about 3 years out of one..it ran great....but lobes did just as you said.

You can have Comp grind same cam on a billet core if you like...make sure you get cast iron dist gear.

Or as you said....call up Crane. I think they have some of the best billet cores out there and I've always had good luck with their cams. They don't always look as hairy on paper...but they deliver the numbers. You gotta pay close attention to "where" each of them is rating stuff from...especially on solids.

I've been using Engle for the last 5-6 years and have nothing but good to say about their quality and customer service. Definitely tops. You can get Mark Engle on the phone and he will spend time to help you out. Plus they buy their cores from Crane!

Lunati is also another good one....call up and ask for Harold...it will be a good long chat about cams and design.


CamMotion is another good smaller company that makes great stuff.


Might check into the Isky Red Zone lifters to last longer or Crowers with HIPPO option. The new Comps have pressurized oiling, but not sure they are advanced as the other two...but they are half the price!


Good luck!!


JIM

 

Hey Jim, thanks for the encouragement!

I am running the Comp Polymer Gear so I will just go with an all billet core.

The lifters all all in perfect shape, including the one that was on the bad lobe. I am surprised the roller has no sign of wear on it.

I would like to keep my valve springs, so I will need to go with a profile that will work with the lower pressure.

Wayne (Motorhead) is running this same cam, so maybe he should have a peak at his every now an then.

I am just very glad I caught it before it did any real damage.

 

Not sure how many miles on those lifters, but I would strongly suggest getting them rebuilt. Comp does a good job with it for a decent price. When a lobe has been running loose (as it wears) it quickly damages the needles in lifters.

I've resigned myself to rebuilding/replacing them every year or so just to be safe. it's no fun when they die.

I now have two sets and I just keep one set in rotation.


JIM

 

Man Travis that stinks !! It sure is disappointing to find something like that when we try to maintain and improve upon our rides.

Now, you need to get your butt in gear and get that thing back to health for the intake comparo

 

I have a Comp Cams cam in my engine

 

Heard a rumor from an engine builder that a shipment of Chinese made cams with bad alloy has made it into circulation. Anyone else heard this?

Message from another board:
I have worked closely with a very good cam manufacturer and I can tell you there are many cams in use and on shelf ready for use that are defective. There are two core suppliers in the country that are bringing in cores from overseas that are a perfect copy of what we produce here and they are causing trouble all over the country. I have had personally engines from three different states with three different cam manufacturers and no one is willing to admit it like always . There are approximately 8500 cores that were brought in.

 

Hey Mike, I am going to the speed shop today to discuss what will be done. I think I am just going to get a billet core of the same grind and have the lifters rebuilt.

The #2 cylinder looking the way it does has me a bit concerned, but I think that hunk of #@(! demon is back to it's old games...

Garys 68: That is not encouraging....Was this cast cores or billet as well?

Thanks!

 

Update: I ordered the same XR280R cam with a Billet Core so I won't have to worry about the material again. This cam has worked great so far and I don't see any reason to change it.

Some more bad news is it looks like the #2 intake valve is bent as the intake runner is full of carbon, it is the only one and the carbon runs all the way up into the manifold.

I will have the motor out tonight, so the cam and that head will be off and to the machinist in the morning.
I ordered the cam with 2 day shipping so it may be here friday.
I am going to replace the #6 exhaust lifter and button it back up and go racing.

 

Hope that you'll get everything back together soon!

 

I'm running my Comp polymer gear on sleaved cam right now. I was too lazy last year to change it off the dist. Now I bought a new Dist and put the poly on it just because it still looked brand new after 25,000 miles.

This is my bad roller - bearings went out and beat up the billet cam also. Crane sold me new better lifters at cost along with another custom billet cam of my choice. I went with Crane Pro rollers hoping to never have bearing failure again.

 

Hey George, I remember when you had that happen, it was ugly.

The motor and cam will be out here in a few hours, if not later tonight.

The polymer gears are incredible, can't say enough good things about it. I will be using it with the new cam.

If Comp grinds the cam ASAP I might have it by Friday, may go racing Saturday/Sunday.

The thing I find the most interesting is the roller that was on the bad lobe is in perfect shape, you couldn't tell at all from looking at it. The roller has no play in it and it feels like it's brand new.

 

I've got 3 motors with comp cams. The only one with significant miles is the one with a High Energy cam. I have an XE268 in another and a hydraulic roller in another. I only have a couple of hundred miles on the one with the XE268. Hopefully, I'll be one of the lucky ones.

 

I don't know everything But this guy at comp cams told me that after they grind the blank that they do a hardening process. That could mean something as simple as using a torch or other means to heat up the cam to about orange glow and then quench it in water. Then you achive some amount of hardnes and they polish it up. When I ordered a custom cam from Comp cams they told me that the reason that it took so long was because all three of them that they had ground failed the hardness test for solid roller extreeme series cams. Well that's when I got on the guys butt about I had ordered a billet custom. no hardening required

So anyway I don't trust Comp cams. To many flat cams. It doesn't matter to me if they sent me new everything. The manhours - gaskets - the worry if you put it together right! No amount of additional money would make up for the lost time that you will never get back.

You must be younger than me my days of thrashing till the wee hours to make a race are over!

 

Sorry to hear about the troubles Travis, looks like you caught it in time. I adjust my valves every 2000 miles or so and the last time they did not really need any adjustment so I am going to let it go a little longer this time.

I pulled my intake to inspect the rollers at the end of last year amd everything looked fine, never thought to look in the lifter bores at the cam lobes though, I thought if the lifters were OK then the cam must be OK I have nearly 10,000 miles on XR280R setup now

 

Billet is a buzz word with no meaning what so ever. A billet is the chunk of metal you begin with. Even a casting can be a billet.

Now if your talking forged!
Forging might not need to be hardened but everything else does.

Even a forging uses a billet. They stick a billet into the machine

 

George: I think it may have something to do with the hardening process as there is not one, but two bad lobes, RIGHT NEXT TO EACH OTHER. The #5 & #6 have the same problem. I will take a picture and post it in a few minutes. I turned 24 about a month ago, the way this is going I'll be sick of it in...oh, 40 years...

Wayne, the problem with this is you won't notice a thing concerning lash as the damage is only on the opening ramp of the lobe, my lash checked out fine as the base circle is undamaged. I don't want to make you lose any sleep, but I sure am glad I checked. This is with ~6000 miles.

Techno: I did not know that, I ASSumed a billet core meant it came from a forging, mostly because that's what they do with cranks. Thanks for the heads up.

 

OK, I have got some pictures.

 

Dang...that be ugly. A couple of years ago, we built a motor for a customer. The cam wiped the lobes. We ate the engine rebuild labor. One guess what kind of cam was in there? We sent it off to the cam grinder, they said "nothing wrong with the hardness".