 Taller fifth gear, Substituting a flipped HB gear in fifth |
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| bluhun |
 Feb 24 2013, 04:52 AM
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#1
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Member  Group: Members Posts: 91 Joined: 23-January 06 From: San Rafael, CA Member No.: 5,464 Region Association: Northern California  |
At the Bay Area meet last week, one owner who is planning a 3.2 liter six conversion also talked about substituting a flipped HB (19:31) gear in fifth in place of the standard ZD (31:22) in order to lower engine revs at highway cruising speed and increase fuel economy. Does anyone have any experience with this transmission modification?
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| RonW |
Feb 24 2013, 09:44 AM
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#2
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Member Group: Members Posts: 76 Joined: 31-December 05 From: Alameda, CA Member No.: 5,340 Region Association: Northern California |
thats an interesting idea, i hadn't heard of that but that makes total sense. now instead of the ZD 0.709 ratio, the flipped HB would be 0.613 ratio
so given 205/50/15 tires ZD @ 3000 rpm = 68 mph flipped HB @ 3000 rpm = 78 mph makes kind of a big jump between 4th to 5th, you could add a Y gear (0.8214) from 4th to have a smoother transition to the flipped HB. Y was used in many 901's for 5th |
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Posts in this topic
bluhun Taller fifth gear Feb 24 2013, 04:52 AM
Luke M Dr. Evil would be the guy to answer this question.... Feb 24 2013, 08:59 AM Mark Henry Talk to Dr. Evil
I'm doing the same I thing H ... Feb 24 2013, 09:36 AM partwerks I think it was an H gear that was used in mine. An... Feb 24 2013, 09:59 AM toon1
I think it was an H gear that was used in mine. A... Feb 24 2013, 10:16 AM kg6dxn I had an H gear with my V8 and Turbo rotary.
With... Feb 24 2013, 10:24 AM Mark Henry I guess it's HA and HB, mine is the HB which i... Feb 24 2013, 10:29 AM toon1
I guess it's HA and HB, I think mine might be... Feb 24 2013, 11:25 AM
Mark Henry
[quote name='Mark Henry' post='1825319' date='Feb... Feb 24 2013, 12:46 PM RonW this is a site i look up gearing
http://www.blues... Feb 24 2013, 12:56 PM shoguneagle There also threads via research which does discus... Feb 24 2013, 01:02 PM |
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