aftermarket bravo gears?
11-27-2014 | 10:10 AM
#1
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From: Cincinnati ohio
aftermarket bravo gears?
The 'bravo build up' thread got me thinking. People were discussing which bravo build up is better. Max machine word, teaque platinum, bravo shop etc. And I believe it was mentioned that they all still share the same weak point of using bravo xr gears. Are the bravo upper gears the true weak point in the bravo drives? Why has no one started cutting gears out of some very strong material (tool steel, chromoly)? On a 5 axis CNC?
11-27-2014 | 10:23 AM
#3
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From: OK CIty, OK
This is just my engineer mind wondering...
Everyone blames the gears because that's the visible representation of a failure. What's not seen is how much the gear housing flex under load. I'm almost positive Merc put strain gauges on them for some real world testing, but we're not privvy to that.
Anyhow, to answer your question- because a stronger gear won't get you anywhere. Gears are extremely efficient for transmitting force when properly designed and installed, but when you have a housing that flexes all of your critical alignments/relationships are toast. Once that happens, the gears eat themselves, whether they're made from S-7 or sharp cheddar.
Everyone blames the gears because that's the visible representation of a failure. What's not seen is how much the gear housing flex under load. I'm almost positive Merc put strain gauges on them for some real world testing, but we're not privvy to that.
Anyhow, to answer your question- because a stronger gear won't get you anywhere. Gears are extremely efficient for transmitting force when properly designed and installed, but when you have a housing that flexes all of your critical alignments/relationships are toast. Once that happens, the gears eat themselves, whether they're made from S-7 or sharp cheddar.
11-27-2014 | 10:37 AM
#5
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From: Delray Beach, FL
Wasnt Smitty doing it?
Anyway, I agree with Cole. I think the cases flex a lot. I used the Max Machine works top cap with 7/16 studs and they worked great. To the point that failures seemed to happen less frequently. Also, I think the cases flex and fatigue. For example, after 1 or 2 failures that drive seems to have problems so maybe they fatigue or get stretched or tweaked over time and abuse levels.
Anyway, I agree with Cole. I think the cases flex a lot. I used the Max Machine works top cap with 7/16 studs and they worked great. To the point that failures seemed to happen less frequently. Also, I think the cases flex and fatigue. For example, after 1 or 2 failures that drive seems to have problems so maybe they fatigue or get stretched or tweaked over time and abuse levels.
11-27-2014 | 11:14 AM
#6
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From: OK CIty, OK
Wasnt Smitty doing it?
Anyway, I agree with Cole. I think the cases flex a lot. I used the Max Machine works top cap with 7/16 studs and they worked great. To the point that failures seemed to happen less frequently. Also, I think the cases flex and fatigue. For example, after 1 or 2 failures that drive seems to have problems so maybe they fatigue or get stretched or tweaked over time and abuse levels.
Anyway, I agree with Cole. I think the cases flex a lot. I used the Max Machine works top cap with 7/16 studs and they worked great. To the point that failures seemed to happen less frequently. Also, I think the cases flex and fatigue. For example, after 1 or 2 failures that drive seems to have problems so maybe they fatigue or get stretched or tweaked over time and abuse levels.
When operating on the thin margins of a high HP engine coupled to a bravo a more thorough rebuild program is needed, something beyond new parts and slappin' 'er back together. It would be great to get a set of factory prints for one. Then a competent machinist could at least assess the case to see if it's jacked up.
