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Roller lifters vs standard lifters

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Old 04-01-2002, 07:31 PM
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Default Roller lifters vs standard lifters

I'm planning a cam & lifter change & am interested to know the difference in horsepower between roller lifters & standard lifters. There is a big difference in price but are the rollers worth it ? Comments & feedback from all are welcome !
 
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Old 04-01-2002, 08:50 PM
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The main reason a roller cam is better is that the lobes can be cut much steeper on both sides. This allows the designer to do all sorts of things that a standard tappet cam can't do. By using these steep lobes you can increase lift and decrease overlap, increase flow velocity, or perform other tuning functions that are not possible with a standard cam. They can develop more horsepower without the excessive overlap that makes an engine "lope" and can have flatter torque curves. You may be able to get the same horsepower from a standard cam as you can from a roller but the engine's other characteristics may suffer.
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Old 04-01-2002, 09:25 PM
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Excellent explanation. In the 450-550 hp range we are talking about 35 hp gain with a roller cam right? Everything else being equal.
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Old 04-01-2002, 09:33 PM
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Plus another grand or so. If you are looking to buy a new cam I had real bad luck with comp cams it took them 6 weeks for my cam. They kept telling me it was on its way.
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Old 04-01-2002, 10:57 PM
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Quote:
Originally posted by formula31
Excellent explanation. In the 450-550 hp range we are talking about 35 hp gain with a roller cam right? Everything else being equal.
With a reasonable idle 35 is probably right. But there are some other tuning options available with a roller-such as a flatter, lower torque curve. In marine app you can also get more hp without reversion problems. There is also a marginal increase in hp due to decreased friction, with lower oil temps.
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Old 04-02-2002, 10:20 AM
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I agree with KCHOTBOAT do not buy anything from Comp Cams it is total ****! I bought a matched cam and spring set after talking to them about my boat and how I use it and they said no problem. The spring they sent were single springs that looked like alot less than the stock Gen 5 but they said they were correct. The springs were installed and shimmed to the correct heights and pressures. Needless to say when I dissassembled the motors 3 months later after dropping a valve I had a total of 8 broken valve springs! I rebuilt the motors again and used the comp cams timing chain that came with the cams last year and at the end of the last season the botton timing chain gear broke. My original purchace of a Comp Cams K kit has cost me over $15000 in repairs due to broken Comp Cams parts. DO NOT BUY ANYTHING FROM COMP CAMS EVER!!!
 
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