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> Bus 4 spd trans, Anybody done this
jwalters
post Jan 21 2005, 06:38 PM
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Sooo Close.......
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(IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif)

Thought of an interesting topic---has anybody put a beefed up bus or t1 trans in the teener----

I loved the gear spacing on my old superbug--and first gear for my car,,well,,,sucks ass--and second is too tall for a good start off--

Would rather spend 650 bucks on a pro-streeter WITH a rhino case and super diff than thousands upgrading my 901--

Sand rail mid engine cable shifter should be able to be adapted rather easily and the trans install is a non-event...

What you think???? (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif)
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jwalters
post Jan 23 2005, 07:55 AM
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Sooo Close.......
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(IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif) Andys---I do admit I have not done this kind of math in a long time, and I do not have my cheat book auto math in front of me--but to kinda look at this from the other side of the coin:

Lets say that high gear is 1:1 + a 4.429:1 R&P , net ratio = 4.429

A .71 and .84 high gear is less than one--we are taking away--hence, subtraction, I do remember that much from the pre algebra course I took ( I am not a mathematician, and do not claim to be, I use cheat sheets all the time)

So this is not a multiplication problem----A 4.429 R&P is being turned slightly more than per engine rotation, or, .29 times more or put into a % --29% more if the input shaft = 1, and it does. Due to the overdriven .71 gearset

With high gear we have taken away tq multiplication--we are now subtracting tq from a 1:1 constant

So now plug this into the equation--

1 - .84 = .16
1 - .71 = .29 These are the difference of our 1:1 constant

We then take these away from our R&P : Because it is being overdriven by this much with our constant of 1 :

3.88 - .16 = 3.72 Final drive The engine is turning 3.72 times per full revolution of the wheel.

4.429 - .29 = 4.139 final drive The engine is turning 4.139 times per full revolution of the wheel.

This is a difference of .419 between the two, not much on paper, but a tremendous amount in practice.

Remember, the high gear is overdriving the input shaft to the R&P, 1:1 is our base constant--if the high gear set was in fact 1:1, but because of the overdriven high gear we must take this difference away from the R&P.
only when the cogs are of a greater value than 1 do they become a Division equation of underdrive, hence, a 12 tooth input meshed with a 27 tooth output you get a ratio, or division of 2.25:1, hence the 12 tooth one will turn 2.25 times for one turn of the 27 toothed one. We are discussing less than one, .71 & .84 This is a division equation of overdrive to be subtracted from the R&P. All underdrive equations are added to the R&P.

The gear sets themselve only multiply torque, this is a theoretical value-they do not multiply themslves, they divide speed for speed.

I hope this makes sense, the term torque multiplication is just that--theoretical tq--the gears are meshed in a multiplicative manner--whatever gear is driving the other it has a constant of 1, no matter how many teeth it has, it is still 1-but by mulitplying 1 you only get the same constant--- therefore-they always divide speed for speed. A division of a ratio of 12:27 is 2.25:1, this does in fact mean that the work output is multiplied by that same constant, 1 x 2.25 = 2.25, or 100 ftlb of tq x 2.25 = 225 ftlb of tq. But work is not tangible, you cannot hold horspower in your hands ( the numerical value) so this stays in theory only.

But I also do admit that I could be wrong--as I stated I am no mathematician, and even I am staring at my avatar a little too much (IMG:http://www.914world.com/bbs2/html/emoticons/wub.gif)
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Posts in this topic
jwalters   Bus 4 spd trans   Jan 21 2005, 06:38 PM
TC/914   I'll tell you what I think if you PM me as to ...   Jan 21 2005, 07:07 PM
736conver   I had a 2.0 914 engine in a type 1 chassis, fiberg...   Jan 21 2005, 07:20 PM
jwalters   http://www.914world.com/bbs2/html/e...   Jan 21 2005, 08:13 PM
736conver     Jan 21 2005, 08:24 PM
Mueller  
  Jan 21 2005, 08:30 PM
SpecialK   <...   Jan 21 2005, 08:36 PM
jwalters   ht...   Jan 21 2005, 09:07 PM
jwalters   ...   Jan 21 2005, 10:27 PM
bondo   Wow, I'm intrigued. How much HP and torque are...   Jan 21 2005, 11:13 PM
Aaron Cox     Jan 21 2005, 11:16 PM
jwalters     Jan 21 2005, 11:53 PM
andys   What are each of the "net" ratios (1 thru 4 x fina...   Jan 21 2005, 11:58 PM
jwalters     Jan 22 2005, 12:13 AM
andys   ...   Jan 22 2005, 12:29 AM
GWN7   I wonder how it would work with a V8?   Jan 22 2005, 01:43 AM
jwalters     Jan 22 2005, 02:10 AM
jwalters     Jan 22 2005, 02:40 AM
SpecialK   I hear ya talkin', but all I see is your avata...   Jan 22 2005, 03:58 AM
redshift   You are never going to be happy with a gear that l...   Jan 22 2005, 05:59 AM
carambola   i don't know about ratio's and stuff like ...   Jan 22 2005, 06:48 AM
scotty b   Bus tranny will bolt right up to a type 4 engine, ...   Jan 22 2005, 08:26 AM
TC/914   I just had RANCHO build a type I swing axle trans ...   Jan 22 2005, 08:57 AM
jwalters   http://www.914world.com/bbs2/html/e...   Jan 22 2005, 09:01 AM
scotty b   TC what did you have to do to mount the vw trans i...   Jan 22 2005, 09:04 AM
jwalters     Jan 22 2005, 09:08 AM
carambola   i appologize must have been thinking of something ...   Jan 22 2005, 10:01 AM
TC/914   Hey Guys, I just got the shipping confirmation fr...   Jan 22 2005, 01:13 PM
jwalters   http://www.914world.com/bbs2/ht...   Jan 22 2005, 02:33 PM
Tom Perso   I had a Rancho IRS trans in my Bug with a 2270cc T...   Jan 22 2005, 06:43 PM
andys   ...   Jan 22 2005, 10:47 PM
reverie   Tom Perso, that was excellent info... thank you...   Jan 22 2005, 11:19 PM
jwalters   http://www.914world.com/bbs2/html/e...   Jan 23 2005, 07:55 AM
Cap'n Krusty     Jan 23 2005, 10:35 AM
jwalters   Yea well the buggie guys are more interested in tr...   Jan 23 2005, 11:02 AM
andys   ...   Jan 24 2005, 12:58 PM
Mueller   Andy, thanks for the link...that is pretty slick ...   Jan 24 2005, 01:17 PM
Cap'n Krusty   ...   Jan 24 2005, 02:52 PM
Tom Perso   The diameter of all the input shafts (that we are ...   Jan 24 2005, 03:25 PM
Cap'n Krusty  

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