 Another trick for you guy building high RPM sixes |
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| TimT |
 Mar 13 2004, 08:49 PM
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#1
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retired  Group: Members Posts: 4,033 Joined: 18-February 03 From: Wantagh, NY Member No.: 313  |
OK...8000 RPM plus...the engine needs some "oiling" help.
have the crank cross drilled... Its mentioned in BAs book... To compliment the cross drilled crank, you have to modify the center main bearing.. Made a fixture to hold a bearing (this can be reversed one end holds a 3.3 the other a different main) A finished bearing is in the fixture in this pic Attached image(s) 
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| TimT |
Mar 13 2004, 08:50 PM
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#2
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retired Group: Members Posts: 4,033 Joined: 18-February 03 From: Wantagh, NY Member No.: 313 |
fixture and bearing chucked in my lathe
Attached image(s) 
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| TimT |
Mar 13 2004, 08:50 PM
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#3
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retired Group: Members Posts: 4,033 Joined: 18-February 03 From: Wantagh, NY Member No.: 313 |
Finished product
Attached image(s) 
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| TimT |
Mar 13 2004, 08:52 PM
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#4
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retired Group: Members Posts: 4,033 Joined: 18-February 03 From: Wantagh, NY Member No.: 313 |
This helps with extended high RPM running....
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| Brad Roberts |
Mar 14 2004, 01:14 AM
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#5
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914 Freak! Group: Members Posts: 19,148 Joined: 23-December 02 Member No.: 8 Region Association: None |
You may need to explain a little more.. I'm sure the person at home who has never seen a 911 main bearing is completely clueless right now.
B |
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| ChrisReale |
Mar 14 2004, 01:18 AM
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#6
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Sleazy Group: Members Posts: 2,665 Joined: 20-January 03 From: San Francisco Member No.: 176 |
Kinda like what you do to rubber suspension bushings?
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| TimT |
Mar 14 2004, 01:22 PM
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#7
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retired Group: Members Posts: 4,033 Joined: 18-February 03 From: Wantagh, NY Member No.: 313 |
OKIE... the way the 911 crank gets oil can lead to the 2&5 rod bearing getting starved for oil during extended high RPM running. This isnt a good thing.
To get a better supply of oil to the center of the crank and the 2&5 rods you cross drill the crank, and cut a groove in the center main bearing.. |
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