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I'm looking to buy an F-cam and was wondering if there is a way to tell if is really an F-cam or not. The guy I'm buying from says that F-303 is written at the end of the cam. Is this right?

Thanks for any help you can provide, Brian
 

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Don't know; I do know that my E303 cam didn't have any external markings that identified it as such.
 

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I own a F-Cam and there are markings on the cam BUT not markings which identify it as an F-Cam. I always wondered why the manufactures did not stamp what type cam it is on the item. I had the same problem with a Wolverine cam I had. There were markings but none which identified the cam. Even when I called several cam companies; Crane or Comp, they were not able to help me.
Unless you know this guy well, be careful. To my knowledge cams just don't come with parts numbers stamped on them.
Good Luck! HTH

BUT, today is your lucky day. In my hand I hold a F-Cam I purchased at Tommie Vaughn. The only markings on it are:

201680 and a letter C with a M inside of it. There is also a small star stamped on it. THOSE ARE THE ONLY MARKINGS!
 

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I think all of this points to a bigger issue - and that is why it's so important to use a degree wheel and dial indicator when any cam is installed. Not only will it allow you to be sure that the cam and timing gear set are manufactured correctly (they often aren't), but you can check to be sure you're putting in the cam you think you are - measure lift, duration, LSA, etc. It's really the only way to be sure. Any other way means you're trusting someone else's judgement or guess.
 

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Man! You see all to often someone mentioning using a degree wheel and dial indicator when installing a cam, BUT to my knowledge I have never seen anyone actually doing this. Most articles I've seen in the mags just lube the thing and shove it in. Very seldom do I see dial indicators used. Is it really too difficult? Is it worth the extra effort? How important is it REALLY?
One day we may get some clarification on this which may help a lot of us "do it yourself ers".
Thanks!
 

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I'm a do it yourselfer and I always use the degree wheel and dial indicator on a cam install (just last Saturday!). It's so nice to know with certainty that the bump stick is opening the valves when it's supposed to. Doesn't matter what the 'dots' are doing, doesn't matter whether things are advanced or retarded compared to the design point. You put the cam in, locate TDC, set up the degree wheel and indicator - - and with an indexed gear set you install the cam so the intake valve is opening however many degrees before or after TDC the cam card says it is supposed to. You can check the intake and exhaust valve openings and closings, calculate advertised and .050" durations, check peak lift both at the cam and the valve to be sure the cam is manufactured accurately. Many (yes the brand names) are not. You can also check piston to valve clearance - a must with any aftermarket cam - unless you're willing to take a risk. You can buy a mag stand, indicator and degree wheel for less than $100. You can make a piston stop device (to determine TDC) for the price of an old spark plug and a 2" long 5/16" bolt (you probably have them laying around). You will learn so much about the way your engine works - as you can tell, I think it's definitely worth it.
 

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Michael Yount said:
You put the cam in, locate TDC, set up the degree wheel and indicator - - and with an indexed gear set you install the cam so the intake valve is opening however many degrees before or after TDC the cam card says it is supposed to.
Not meaning to take out just I want to see but, are you saying I could have used the indexed gear and installed my F-Cam advanced 4 degrees vice straight up(0 on the index gear)? The card says it is manufactured 4 degree advance.

Or is this another topic?
 

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Your question makes the point for me - you can use an indexed gear set to alter the timing (in the case of mine) in 2 degree increments over a 16 degree spread. But unless you check it with indicator and degree wheel, you're assuming your cam manufacturer and timing set manufacturer are accurate with their products. They are not always. Lots of stories out there of people with - you pick 'em - Crane, Ford Racing, TFS, even Comp Cams installing them 'dot to dot' = straight up = O degrees advance/retard, and later for other reasons, checking them to find out they were 2, 3, 4 degrees off. In other words, if the cam card said the intake was supposed to open .004" lift at 28 BTDC, they found out when it was installed dot to dot that it was actually opening at 24 BTDC or 30 BTDC.

Buddy Rawls who handled my custom for me, told me that he's gotten custom grinds from CompCams as much as 4 degrees off. He knows it 's the cam because he's got a timing set which he's checked and knows to be accurate. Buddy always mocks them up before he sends them out; and if you send him your timing set, he'll mark it up for you with the cam so you know you've got a proper install - esentially he's doing the degreeing for you in that case. The lift, LSA, and durations were all accurate on mine, but according to his mockup, the cam was ground 1 degree advanced - that is, instead of the .050" lift occurring at 5 degrees ATDC as he specified when he ordered it, it was occurring one degree early at 4 degrees ATDC -- when he mocked it up 'dot to dot'. Since my index set allows changes in 2 degree increments I had a choice. I could set it at the zero dot to dot mark - and I measured the same 4 degrees ATDC at .050" lift that Buddy did, which would mean the cam was actually installed 1 degree advanced; or I could set it at at the 2R mark (2 degrees retarded according to the gear set), and when I measured that, the intake was opening 2 degrees later at 6 degrees ATDC -- which is equal to an actual 1 degree retarded set up. I chose the former - I put it in dot to dot which in my case is actually 1 degree advanced. Given the rotation of the engine, as mileage goes up and the chain stretches, installing a degree or 2 advanced will allow actual timing to be just about right.

When your specs say the cam is ground with 4 degrees advance, hopefully you can see now what that means. If you were to put the indexed setting at 4A, theoretically you would have added an additional 4 degrees advance for a total of 8. If you put it at 4R, theoretically you would have 'undone' the manufactured 4 degree advance, returning it to a 0degree install. I say theoretically because - you know what's coming - unless you check it with degree wheel and indicator - you're assuming they manufactured it accurately.
 
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