what makes higher hp engines less durable
10-10-2014 | 05:09 PM
#1
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From: Ontario, Canada
what makes higher hp engines less durable
These motors have higher quality everything built with much more precision and run at similar rpm compared to black engines. I assume it has to do with the power generated by combustion but in sure there is a better reason. If I put top of the line heads and a bob madera cam on my 502 shouldn't reliability be improved? I hear that blue motors need freshening at 300 hours
Last edited by stimleck; 10-10-2014 at 06:06 PM.
10-10-2014 | 06:46 PM
#3
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From: On A Dirt Floor
Valvetrain mostly.
With good breathing stuff,
For more hp you need more 'cam' and more rpm.
More lift usually creates more valvetrain stress. Add the two together = More rpm means spinning your cam faster thus more lift more often.
For BBC:
.500 lift very little maintenance if any (black motors)
.600 lift moderate maintenance (blue motors)
.700" lift very tight maintenance schedule. (big ballz motors...Lol)
Edit in: in case someone want to go deep on this: Above very generic info but will give OP what he is looking for right now.
With good breathing stuff,
For more hp you need more 'cam' and more rpm.
More lift usually creates more valvetrain stress. Add the two together = More rpm means spinning your cam faster thus more lift more often.
For BBC:
.500 lift very little maintenance if any (black motors)
.600 lift moderate maintenance (blue motors)
.700" lift very tight maintenance schedule. (big ballz motors...Lol)
Edit in: in case someone want to go deep on this: Above very generic info but will give OP what he is looking for right now.
Last edited by SB; 10-10-2014 at 07:11 PM. Reason: Above very generic but will give you what you are looking for
10-10-2014 | 07:05 PM
#4
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Joined: Sep 2013
Posts: 334
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From: Oklahoma sticks
Parts too hold power need replaced. I have a 800 hp small block with about 50000 miles and don't miss a beat. But I change valve springs and lifters about once every two years. I never have had a problem lower end. Just valve train and that's because it has too breathe
10-10-2014 | 07:33 PM
#5
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Posts: 10,042
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From: Toledo Oh
Valvetrain mostly.
With good breathing stuff,
For more hp you need more 'cam' and more rpm.
More lift usually creates more valvetrain stress. Add the two together = More rpm means spinning your cam faster thus more lift more often.
For BBC:
.500 lift very little maintenance if any (black motors)
.600 lift moderate maintenance (blue motors)
.700" lift very tight maintenance schedule. (big ballz motors, Cslobs low hp wonder motors...Lol)
Edit in: in case someone want to go deep on this: Above very generic info but will give OP what he is looking for right now.
With good breathing stuff,
For more hp you need more 'cam' and more rpm.
More lift usually creates more valvetrain stress. Add the two together = More rpm means spinning your cam faster thus more lift more often.
For BBC:
.500 lift very little maintenance if any (black motors)
.600 lift moderate maintenance (blue motors)
.700" lift very tight maintenance schedule. (big ballz motors, Cslobs low hp wonder motors...Lol)
Edit in: in case someone want to go deep on this: Above very generic info but will give OP what he is looking for right now.
fixed it for you....
10-10-2014 | 07:39 PM
#6
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From: On A Dirt Floor
10-10-2014 | 07:56 PM
#7
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Posts: 4,189
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From: Cape coral, FL
The whole engine doesn't need rebuilding at 300. Top ends need freshening. Higher quality parts but under a lot more stress. As long as proper top end maintenance is done bottom ends will last a long time. Got a friend with a 42 fountain. Over 600 hrs on bottom ends. Motors never been out of boat. Just top ends. These are merc 454/420 with blowers (525sc clone).
10-10-2014 | 08:12 PM
#9
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From: Toledo Oh
Stimlek...its not that either are more or less durable....
Your a motor, you walk all around the park all day long....no big deal, you run around the park all day.. at the end of the day your more tired after running all day than walking, but your the same Stimlek, no more or no less durable at the beginning of the day, at the end of the day, running is harder than walking.
Your a motor, you walk all around the park all day long....no big deal, you run around the park all day.. at the end of the day your more tired after running all day than walking, but your the same Stimlek, no more or no less durable at the beginning of the day, at the end of the day, running is harder than walking.
Last edited by phragle; 10-10-2014 at 08:15 PM.
10-10-2014 | 08:51 PM
#10
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Posts: 1,037
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From: FredVegas, Va
The main reason for the "top end rebuild" is to change the valve springs and sometimes rocker arms.
To make more power, you need more air which = more cam.
More cam = less valve spring life.
