Edelbrock/Comp Cams
- Thread starter mikedrini
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I wonder if they’ll improve QC?
mikedrini
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Good call Matt, I've honestly only bought one thing from Edelbrock (Performer Intake for my 383), but I've never heard anything bad per se. Comp Cams on the other hand seems to be hit or miss depending on who you talk to.
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Once bitten twice shy. I’ll not buy Comp cams again.
Mike66Chryslers
Senior Member
So now most speed equipment will be made by one of two companies, the one that owns Edelbrock or the one that owns Holley. 
This may be outdated information, but I read that there are only two companies that supply most aftermarket cam blanks, and some finished cams, for domestic applications. Edelbrock uses the same supplier as Summit, and a lot of their cams have Chevy lobe profiles. Mopars use larger diameter lifters, so they can use lobes with faster ramps to open the valve quicker/higher for more power, versus a Chevy-grind cam with the same duration.
I know Comp makes cams specifically for Mopars which take advantage of this, such as their Extreme Energy series. That probably makes them more sensitive to metallurgy, geometry and break-in issues, which would affect failure rate.
I have Edelbrock carbs and intakes but Comp cams in both my Chryslers. I've had an issue with Comp but with their lifters, not the cam. I used a mild cam in one of their older "High Energy" grinds in my convertible. It's a cruiser, not a hot rod, so I wanted reliability and a quiet valvetrain in that car with a stock-ish performance level.
One the engine heats-up and the oil (Rotella 15w40) thins out, some of the lifters in my convertible start to bleed down and clatter as if the engine had solid lifters. I've inspected and adjusted the valvetrain geometry with shaft shims and custom-length pushrods to ensure it is perfect. Also removed and disassembled the lifters to inspect for internal problems. The next thing I want to try is swapping-out the lifters for new ones (not Comp) and doing a new break-in.
This may be outdated information, but I read that there are only two companies that supply most aftermarket cam blanks, and some finished cams, for domestic applications. Edelbrock uses the same supplier as Summit, and a lot of their cams have Chevy lobe profiles. Mopars use larger diameter lifters, so they can use lobes with faster ramps to open the valve quicker/higher for more power, versus a Chevy-grind cam with the same duration.
I know Comp makes cams specifically for Mopars which take advantage of this, such as their Extreme Energy series. That probably makes them more sensitive to metallurgy, geometry and break-in issues, which would affect failure rate.
I have Edelbrock carbs and intakes but Comp cams in both my Chryslers. I've had an issue with Comp but with their lifters, not the cam. I used a mild cam in one of their older "High Energy" grinds in my convertible. It's a cruiser, not a hot rod, so I wanted reliability and a quiet valvetrain in that car with a stock-ish performance level.
One the engine heats-up and the oil (Rotella 15w40) thins out, some of the lifters in my convertible start to bleed down and clatter as if the engine had solid lifters. I've inspected and adjusted the valvetrain geometry with shaft shims and custom-length pushrods to ensure it is perfect. Also removed and disassembled the lifters to inspect for internal problems. The next thing I want to try is swapping-out the lifters for new ones (not Comp) and doing a new break-in.
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Lifters were my issue as well. They didn’t open valves very well for very long. It took a bit of time to diagnose as well because the performance issues were intermittent and I did find other causes for some of the issues I was having. Fresh engine and eventually the lifters came out and went in the garbage with less than a thousand miles on them.
70bigblockdodge
Old Man with a Hat
Lifters are always the problem.
Cam grinding machines are still here no matter where the blank comes from.
The lifters however have been sent overseas once the OEMs stopped using flat tappets.
You have to buy lifters from a reputable source, comp ain't it.
Cam grinding machines are still here no matter where the blank comes from.
The lifters however have been sent overseas once the OEMs stopped using flat tappets.
You have to buy lifters from a reputable source, comp ain't it.
mikedrini
Well-Known Member
Good to know gentlemen, thanks for the advice. I am doing my first build as we speak (440/505 stroker) and I opted for a Howard's Solid Flat Tappet with Howard's lifters. Hopefully that works out. I had heard and read quite the mixed bag when it came to Comp, which steered me away. I still gave them a fair chance and called to talk to a rep who began our conversation (after a brief email exchange) with "C'mon Mike, you yankin me around or are we gonna get this done?" Then come to find out he didn't have the answers to some of my questions and would answer most of my questions with a "That's a good question, hmmm". He sounded like a routine salesman who wasn't knowledgeable about the product he sold. Which I get, given the size of the company, but also given that was my lone experience with the company, I was turned off.
I went with Howard's hydraulic roller lifters with my custom grind Comp Cam. I had heard horror stories about the Comp Cam rollers. I have heard of hydraulic roller lifters collapsing but my build is mild with not high lift or high rpm's. I think the advantage with the roller will be it's ability to hold the valve wide open for much longer time that a flat tappet. This should help my HP exhaust manifolds breath a little better.
That's the theory anyways.
That's the theory anyways.
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I have a Comp Cams extreme energy cam and a set of Crane lifters came with it, hope it works fine.
mikedrini
Well-Known Member
Yeah, I was nervous about a roller cam after hearing about some compatibility issues with roller cams and roller lifters in 440's. For my first build I stuck with the flat tappet, maybe the second time around I will look into a roller.
Can't say with any authority if one is better than another. I have heard horror stories with both rollers and flat tappet systems. Wish me luck and I wish you and LocuMob luck too.
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What put Comp Cams "on the map" was their High Energy series of cams debut in the later '70s. Prior to that, all cam lobes were assymetrical in shape. The HE series opened the valve quicker and closed it slower. "More area under the curve" without increasing stated duration. A neat trick. The HE 268 worked well in Chevy 350s. Only thing was that for the first 10K miles or so, with the hydraulics adjusted correctly (like .5 turn preload), it sounded like a flat tappet cam. Nobody every could explain why, but it finally quietened down later, with no loss in performance.
I got a HE268 for a 440 I was going to build, a NOS 440motorhome short block. I put the cam in it, put a degree wheel on the crank, with a timing chain, and then rolled it over to get the cam specs and such. Everything happened as it was supposed to. BUT what I was surprised at was that the valve stayed open for a full 10 degrees of crank rotation. By comparison, the MP Street Hemi 284 cam held max lift for only one degree of crank rotation. All of this was going on in the middle 1980s.
BEFORE the issues of "lobe circle diameter" or lifter diameter became known to all. Then Hughes Engines got "big enough" to have their Chrysler lobe circle/lifter diameter cams built for them. Met them at Mopar Nats one year, which was neat. Plus their "step dome" (makes "quench" with an open chamber head) pistons. Neat stuff, especially back then!
Edelbrock has been selling camshafts for years. As a part of their "top end kit" heads, intake, cam, etc. It seems that Comp's product selections have become onerous in the past decade or so. TOO many different cam lines, some of which overlap. TOO many choices, by observation. Plug them into their engine dyno program and some have about 5 horsepower between them!
Look at how many of the old-line hot rod brands that is under the Holley umbrella. Perhaps Edelbrock sees that as "the future"? Who knows where it's going to end?
Enjoy!'
CBODY67
I got a HE268 for a 440 I was going to build, a NOS 440motorhome short block. I put the cam in it, put a degree wheel on the crank, with a timing chain, and then rolled it over to get the cam specs and such. Everything happened as it was supposed to. BUT what I was surprised at was that the valve stayed open for a full 10 degrees of crank rotation. By comparison, the MP Street Hemi 284 cam held max lift for only one degree of crank rotation. All of this was going on in the middle 1980s.
BEFORE the issues of "lobe circle diameter" or lifter diameter became known to all. Then Hughes Engines got "big enough" to have their Chrysler lobe circle/lifter diameter cams built for them. Met them at Mopar Nats one year, which was neat. Plus their "step dome" (makes "quench" with an open chamber head) pistons. Neat stuff, especially back then!
Edelbrock has been selling camshafts for years. As a part of their "top end kit" heads, intake, cam, etc. It seems that Comp's product selections have become onerous in the past decade or so. TOO many different cam lines, some of which overlap. TOO many choices, by observation. Plug them into their engine dyno program and some have about 5 horsepower between them!
Look at how many of the old-line hot rod brands that is under the Holley umbrella. Perhaps Edelbrock sees that as "the future"? Who knows where it's going to end?
Enjoy!'
CBODY67
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