Buying used cams yay or nay?
11-30-2010, 03:35 AM
#11
Havoc
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11-30-2010, 06:40 PM
#12
ahhhh
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Re: Buying used cams yay or nay?
Unless you have some way to identify exactly what they are, and they are in like-new or almost-new condition, I wouldn't bother.
About the breakin: Decent quality cams with low mileage shouldn't wear to the point where different rockers should be a problem, as long as the rockers are new or low mileage. It's like anything else, if one part is worn and the other isn't, they aren't going to work well together. One hardened part that wears very little mated to another hardened part that wears very little usually work ok together because the wear during breakin is very low for both parts. Obviously if one part has much higher mileage than the other, it's a lot more likely that there will be differences in surface wear and surface shape, which is why it's somewhat important that the rockers aren't too worn.
That being said, a lot of people swap new cams into high mileage stock valvetrains.
Really the biggest problem is that it's usually really hard to verify what you're actually buying in terms of brand, specs, etc... It's also hard to verify how the cam was treated during install and removal, and any hidden damage is pretty difficult to spot. Soooo it's always a gamble when you're buying used cams unless you know the skill/reputation/honesty of the previous owner. Cams are hard to identify and somewhat fragile so make sure you trust the person selling.
I dunno, I always have this mental picture of some eBay seller dropping one of the cams while boxing them up, and saying "oh well, they'll never know" and then shipping them out.
About the breakin: Decent quality cams with low mileage shouldn't wear to the point where different rockers should be a problem, as long as the rockers are new or low mileage. It's like anything else, if one part is worn and the other isn't, they aren't going to work well together. One hardened part that wears very little mated to another hardened part that wears very little usually work ok together because the wear during breakin is very low for both parts. Obviously if one part has much higher mileage than the other, it's a lot more likely that there will be differences in surface wear and surface shape, which is why it's somewhat important that the rockers aren't too worn.
That being said, a lot of people swap new cams into high mileage stock valvetrains.
Really the biggest problem is that it's usually really hard to verify what you're actually buying in terms of brand, specs, etc... It's also hard to verify how the cam was treated during install and removal, and any hidden damage is pretty difficult to spot. Soooo it's always a gamble when you're buying used cams unless you know the skill/reputation/honesty of the previous owner. Cams are hard to identify and somewhat fragile so make sure you trust the person selling.
I dunno, I always have this mental picture of some eBay seller dropping one of the cams while boxing them up, and saying "oh well, they'll never know" and then shipping them out.
Thanks, I need Mivec Cams.
Last edited by split; 11-30-2010 at 06:44 PM.
11-30-2010, 08:26 PM
#13
braap braap
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Re: Buying used cams yay or nay?
Had that happen... to a set of 600 dollar Skunk Pro1s. The seller said 'they weren't like that'. I forget which postal service was used but they covered half of the cost. So I got one cam and half the money back. yay.