Thread: Cam Help!

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Hey just wondering how to figure out what cam i have. I got a cam from a buddy and didnt get any information with it so im wondering the lift and duration. It's stamped from timing gear end to rear distributor end like so:

cwc
D5 C5
O6 E6


I 5 1539

Just wondering if anyone can help I called comp cams and it wasnt theres
My buddy said it was a decent cam too like a $160 new I dont think he's lying to me but I need to know what it is.

Thanks

What engine is it intended for?

Is this a brand new, in the box, never used cam? If not - it's really tough to ID. If it's used, you'd be well advised to just let it go..

I'd never install an already run cam in any engine other than the one it was run in as they immediately take on a personality that is unique to each engine.

My 2 cents,
Glenn

Agree with Glenn. If the cam is used, it's best future use is as a door stop.

The CWC stands for Campbell Wyatt and Cannon, the foundry that cast the cam blank. The blanks are then sold to various OEM and aftermarket manufacturers to be finish-ground into a useable product.

When manufactured, a flat tappet camshaft lobe will have an angle to it as you hold the cam out in front of you and look along its length. The taller side of a lobe will be several thousandths of an inch taller than the shorter side of the lobe. It is this tall side that engages the convex surface of the lifter to spin the lifter in its bore. The lobe therefore does not scuff on the lifter face, but rather engages the lifter face and more or less stays at that particular point of the lifter face to walk the lifter around in its bore. Camshafts and lifters "wear in" to a particular pattern, just as piston rings do in the cylinder bore. If you remove the cam from one motor and install it in another motor, there is little chance that the relationship of each and every lobe will be exactly the same as it was when the cam and lifters were broken in in the previous motor and the majority of the time, the cam/lifters will fail.

Sometimes a guy will get lucky, using a used cam in another motor with new lifters, but most of the time, this is a fool's game. Cams are relatively inexpensive, so the best bet is to begin with a new cam and new lifters and let them wear in together. If you use a dial caliper or micrometer and measure from the heel to the nose of each lobe, you will be able to determine if the cam is reuseable or not. For instance, if one side of the lobe measures 1.250" and the other side of the lobe measures 1.254", then the angle is still there from one side of the lobe to the other and the cam can probably be reused with new lifters. If it measures, for instance, 1.250" on one edge and 1.250" or 1.251" on the other edge, then the cam is worn out and should be used only as a door stop.

The previous explanation applies only to flat tappet cams and lifters. Roller tappet cams and lifters are a whole different animal and can be re-used motor to motor indefinitely as long as they remain structurally sound. Holding a roller cam out in front of you in the same manner as described above will reveal that there is no difference in dimensions from one side of the cam lobe to the other. They are cut "square" because the lifter does not have to spin in its bore. Matter of fact, that would be catastrophic. The roller tappet wheel must be restricted to one position so that the wheel of the lifter rolls on the cam lobe. To turn the lifter wheel one way or the other would scuff both the lobe and the lifter wheel, sort of like a screeching tire on the pavement when a car "pushes" going into a turn (steering wheel is turned one way or the other and the car is still pushing straight ahead).

Tech,
Not to hijack the thread, but since a roller cam is cut square is it still advisable to break in the new cam for the 20 minutes at nominal 2000 rpm's when first started? It seems logical that this is critical to a flat tappet cam, in order to establish the lobe/lifter relationship you describe, but is the procedure the same for a roller cam?

Originally Posted by rspears

Tech,
Not to hijack the thread, but since a roller cam is cut square is it still advisable to break in the new cam for the 20 minutes at nominal 2000 rpm's when first started? It seems logical that this is critical to a flat tappet cam, in order to establish the lobe/lifter relationship you describe, but is the procedure the same for a roller cam?

there is on break in on a roller there no lobe relationship other then the roller rolls over its lobe that is all there should be .Sorry not Tech thats what your thust button or trust plate is used for. the hi load seen over the face of the cam you want it flat . over the years they have work on the rollers of the lifters and finsh .a off set loads roller and will wear out lifters if it skids or start to track in the cam bad things are going to start .i put alot of roller cams in and have many ground for my shop . so i could not help my selfdone many roller engines with them not just 20 or so

Thanks, Pat. I did not think there was any "break in" for a roller, but this was a good opportunity to be sure.

Thanks Pat, we're on the same page.

The cam is brand new never been used it jsut never came with a box. I was reading other forums and people with the same I 5 1539 code said it was a 350/350 LT1 aftermarket re grind. It is intended for a chevy small block

Anyone around your area have a cam check stand and indicator??? If you could find one, you could at least determine the lift, and with a little ingenuity with the degree wheel you could determine all the cam's specs... A lot of time and effort, probably easier to just buy a cam that would be correct for the engine you have or are building???? Without a cam card or a cam check stand, it's pretty much who's word you want to take as to what it is.... Or, just install it in a short block and degree it out... Guess I'd like to know for sure what I have before I install it.....

The 1970 LT-1 was an engineering triumph in 1970 as a combination of components that performed very well together and made for an incredible engine. Some say it is one of the five best engines to ever come out of GM. It red lined at 6500 RPM and the valve train was proofed to 7200 RPM. The 1970 LT-1 also had 11:1 compression (factory advertised) and ran on “premium fuel only” and was not available with an automatic.

If your cam is truly an LT-1 copy, the specs are: 242/254 @.050", .458/.485" lift, and 116 lobe separation. It’s a mechanical (solid) cam and needs a lot of care and feeding in the form of regular valve adjustment. The original LT-1 was optimized for the GM factory cast iron manifold, that’s the reason for the longer exhaust duration and the wider lobe centers (116 versus 114 on the “header” version of the cam used in Z-28 – GM Part Number 3849346 which was also used in the 365 horse 327)..

Unless you’re prepared to “go all the way” and re-create an LT-1, don’t use this cam. You’d be better served to use it as a conversation starter and tell stories about the “legendary LT-1 Corvette engine….”

As is continually discussed on this site – the correct way to build an engine is to start with a clean piece of paper and build from the back forward. The rear end and transmission decisions should be considered before developing an engine build. Case in point – the cam you’ve got (if it is an LT-1) was not even available in an automatic version in the Corvette because there was no practical rearend/transmission combination with a TH400. Even with the four speed and a 3.73 rear end, it was hard on clutches. An automatic would have been a disaster off the line but would have run like jack-the-bear when you nailed it at 70 and it downshifted!

Think about what you want to do with your car – then let us help you decide which pieces and parts will allow you accomplish the dream. This cam is way too much for a “weekend project” and would provide lots of disappointment if not combined with all of the correct parts. It will have a really lumpy idle – but there’s a lot more to making usable horsepower than an impressive idle. The guys in their “Subaroos and Hondos” would eat you alive if you stuck this cam in an otherwise stock 350.

Regards,
Glenn

That there is some really good advice IMO ......................

Kitz

ok thanks for all the information im just gonna set it aside.

You can Check Camshaft Lift with a Caliper . Then you X's that Number by the Rocker Arm Raito Hot Rod Math Stuff .