 Tranny Gearing. |
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| 749142 |
 Feb 18 2008, 10:55 PM
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#1
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Member  Group: Members Posts: 254 Joined: 8-January 08 From: Bakersfield, Ca Member No.: 8,545  |
Hey guys.
does anbydody know about regearing a 914 transmission with a steeper final drive ratio differential. do they make aftermarket differentials? if so any links? thanks steven |
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| Bleyseng |
Feb 18 2008, 10:59 PM
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#2
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Aircooled Baby! Group: Members Posts: 13,036 Joined: 27-December 02 From: Seattle, Washington (for now) Member No.: 24 Region Association: Pacific Northwest |
The final drive/5th gear setup was setup to keep the fan moving at the right speed for cooling.
Changing that for a street car means looking at how you will cool the engine. |
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| 749142 |
Feb 18 2008, 11:18 PM
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#3
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Member Group: Members Posts: 254 Joined: 8-January 08 From: Bakersfield, Ca Member No.: 8,545 |
QUOTE(Bleyseng @ Feb 18 2008, 08:59 PM)  The final drive/5th gear setup was setup to keep the fan moving at the right speed for cooling. Changing that for a street car means looking at how you will cool the engine. my dad has done such extensive polishing to my heads and pistons that my engine runs about 65 degrees cooler than stock. so there for if i can gear it steeper i can get back some of that heat for efficiency and then have more topend if i have the power and have more efficiency becuase of lower rpms. i have video of my heads that are polished. they look like mirrors. you can see the reflection of my dad with the camera in the valves. it took him about 4 months to do the two. but it was well worth it. next best thing from ceramic coating. steven |
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| jd74914 |
Feb 18 2008, 11:30 PM
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#4
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Its alive Group: Members Posts: 4,843 Joined: 16-February 04 From: CT Member No.: 1,659 Region Association: North East States |
QUOTE(749142 @ Feb 19 2008, 12:18 AM) QUOTE(Bleyseng @ Feb 18 2008, 08:59 PM) The final drive/5th gear setup was setup to keep the fan moving at the right speed for cooling. Changing that for a street car means looking at how you will cool the engine. my dad has done such extensive polishing to my heads and pistons that my engine runs about 65 degrees cooler than stock. so there for if i can gear it steeper i can get back some of that heat for efficiency and then have more topend if i have the power and have more efficiency becuase of lower rpms. i have video of my heads that are polished. they look like mirrors. you can see the reflection of my dad with the camera in the valves. it took him about 4 months to do the two. but it was well worth it. next best thing from ceramic coating. steven How do you know it runs cooler than stock? Polishing does not help you loose heat. If you polish the inside of your ports and combustion chambers you increase surface tension and hurt mixing, and if you polish the outside you loose surface area over the rough castings (heat exchange is dependent on surface area). (IMG:style_emoticons/default/wacko.gif) |
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| 749142 |
Feb 18 2008, 11:46 PM
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#5
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Member Group: Members Posts: 254 Joined: 8-January 08 From: Bakersfield, Ca Member No.: 8,545 |
QUOTE(jd74914 @ Feb 18 2008, 09:30 PM) QUOTE(749142 @ Feb 19 2008, 12:18 AM) QUOTE(Bleyseng @ Feb 18 2008, 08:59 PM) The final drive/5th gear setup was setup to keep the fan moving at the right speed for cooling. Changing that for a street car means looking at how you will cool the engine. my dad has done such extensive polishing to my heads and pistons that my engine runs about 65 degrees cooler than stock. so there for if i can gear it steeper i can get back some of that heat for efficiency and then have more topend if i have the power and have more efficiency becuase of lower rpms. i have video of my heads that are polished. they look like mirrors. you can see the reflection of my dad with the camera in the valves. it took him about 4 months to do the two. but it was well worth it. next best thing from ceramic coating. steven How do you know it runs cooler than stock? Polishing does not help you loose heat. If you polish the inside of your ports and combustion chambers you increase surface tension and hurt mixing, and if you polish the outside you loose surface area over the rough castings (heat exchange is dependent on surface area). (IMG:style_emoticons/default/wacko.gif) (IMG:style_emoticons/default/WTF.gif) its just physics. when you polish the chambers. you remove surface area. the casting has peaks and valleys if you stretched those peaks and valleys out its more surface area, which collects more heat. if you remove those peaks and valleys the chambers dont soak up that heat. that heat is therefore used more in pushing the piston instead of being soaked up in the chambers. your right in saying that polishing doesnt help you lose heat, when you polish that extra heat was never able to be soaked up by the chambers in the first place. and i have seen the results first hand on my car. and im not sure wut you mean by surface tention and hurt mixing?(typo?). polishing the chambers helps keep the engine run cooler but polishing the rough castings on the outside of the head is counterproductive. steven |
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Posts in this topic
749142 Tranny Gearing. Feb 18 2008, 10:55 PM
jd74914
:WTF:
its just physics. when you polish the cha... Feb 18 2008, 11:57 PM 749142
:WTF:
its just physics. when you polish the ch... Feb 19 2008, 05:46 PM
toon1
Hey guys.
does anbydody know about regearing a 91... Feb 18 2008, 11:12 PM 749142 I've looked into it, BUT most of the options o... Feb 18 2008, 11:34 PM AgPete139 :ttiwwp: Feb 18 2008, 11:22 PM toon1
[quote name='Bleyseng' post='999500' date='Feb 18... Feb 18 2008, 11:39 PM 749142
[quote name='Bleyseng' post='999500' date='Feb 1... Feb 18 2008, 11:51 PM toon1 205/65's are close to stock height
17... Feb 18 2008, 11:47 PM toon1 :popcorn:
[quote name='749142' post='999507' dat... Feb 18 2008, 11:49 PM 749142 hey jd74914
tell me something. have you ever run ... Feb 18 2008, 11:55 PM Dr Evil Click on the gearing links in my sig line for more... Feb 19 2008, 11:23 AM Bleyseng An easier trick is to use a different cam than sto... Feb 19 2008, 11:02 PM 749142
An easier trick is to use a different cam than st... Feb 19 2008, 11:36 PM |
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