 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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| toon1 |
Feb 24 2013, 11:25 AM
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#2
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Senior Member Group: Members Posts: 1,849 Joined: 29-October 05 From: tracy,ca Member No.: 5,022 |
QUOTE(Mark Henry @ Feb 24 2013, 08:29 AM)  I guess it's HA and HB, I think mine might be the HA which is a bit lower ratio when flipped. I think peeps call it an H gear when really it's an HB? Anyone know what my final ratio and RPM's would be with a flipped HA and 205/60-15 tires? (IMG:style_emoticons/default/smile.gif) It's gonna get you back close to stock gearing, maybe a touch taller. I was running 195/60/15's and that's about 4.7%under driven. There is a gear chart/rpm/tire size XLS chart in the archives somewhere that Aaron cox posted a long time ago that you can change the tire size and it will give you a final output. The someone was able to also add flipped gears to the chart to give a taller gear ratio and different tire size ratio's. If you can find it it will tell you what your ratio's will be. |
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| Mark Henry |
Feb 24 2013, 12:46 PM
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#3
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
QUOTE(toon1 @ Feb 24 2013, 12:25 PM) QUOTE(Mark Henry @ Feb 24 2013, 08:29 AM) I guess it's HA and HB, I think mine might be the HA which is a bit lower ratio when flipped. I think peeps call it an H gear when really it's an HB? Anyone know what my final ratio and RPM's would be with a flipped HA and 205/60-15 tires? (IMG:style_emoticons/default/smile.gif) It's gonna get you back close to stock gearing, maybe a touch taller. I was running 195/60/15's and that's about 4.7%under driven. There is a gear chart/rpm/tire size XLS chart in the archives somewhere that Aaron cox posted a long time ago that you can change the tire size and it will give you a final output. The someone was able to also add flipped gears to the chart to give a taller gear ratio and different tire size ratio's. If you can find it it will tell you what your ratio's will be. I remember that chart, I can't find it now and IIRC it didn't tell me what ratios a flipped HB would be. |
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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 RonW thats an interesting idea, i hadn't heard of t... Feb 24 2013, 09:44 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
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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