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caroni. I will share the imfo on my caliper conversion, but beware, you might be flamed alittle about you alfa ford porsche spider:w00t::w00t:... what driveshaft are you going to use?
 

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Snap of S10 short shifter in GTV, just changed the oil by pouring it down the shifter, works but patience is required.
Re strength of box , at last outing on track I was coming down straight flat out in 4th, braked for a 3rd gear corner and put it in 1st , it went straight in, put the car sideways but no complaints from box, still not planning to do it again.
Box is taking some getting used to , had a moment on a recent hillclimb where I couldn't get a clean gearchange ,I think changing from 2 to 3 lost a second , maybe 2 and that was enough to ruin the run , and the day as it turned out, will be quicker next year.
 

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Bianchi,

I had an old ford driveshaft with the correct u-joint and slip-joint for the T-5 so I had it cut down, flange welded on and balanced. It is steel but it is also a tiny bit to big for the e-brake. Like your aluminum one. It is so close I'm going to try to massage the e-brake lever and see if it will work. If not I will go with a slightly narrower steel one. Although aluminum would be nice I want to keep the original e-brake set up. I'm not trying to produce gobs of power, maybe 600bhp on a good day! :clown: Just kidding. ≈200 would be nice though.

As to the flaming... I have read many of the caring and embracing comments directed your way over the years so I guess I know what to expect. That is why I joined SNO a few years ago.

I look forward to learning about the brake conversion. Thanks for being willing to share. I did some creative work on the speedo and tach if you are interested in seeing pics. Let me know I'll post them under another topic heading.
David (caroni)
 

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just for fun , asked local dyno guy about the diff between a alumiumn drivesaft and a 1 piece steel on,, he pulled out charts.. 1.5 more hp to the rear wheels and 5.5 more tq. to the rear wheels then he showed me a conversion from a two piece d/shaft to a 1 piece alu d/shaft 4.5 more hp to the rear wheels and 12.4 more tq to the rear wheels that 2 piece d/shaft hade only reg. ' u ' joints not rubber flex disk at the front.. he thought that may be more hp/tq loss at the rear wheels.
 

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Interesting -- easy reliable horsepower gain, by the time you get to around 180hp its takes a lot to get that much extra out of the engine
 

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Richard Jemison
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Bianchi`s dyno page

Sorry, but that`s crapolla.

There is no reason that a lighter driveshaft increases "power" to the wheels. It might have an effect on "speed of acceleration" but a significantly small one as the diameter of the masses involved are too small.

You are most likely seeing differences in the engines operating temp, outside temp or operator performance. Look at the separation.

The engine makes HP, not the other components and specifically a non significant component like a driveshaft.

If you want to make a driveline change that will make an improvement, differentials with pinions centered on the ring gear rather than offset below center are more efficient. Ie: some Chrysler types, quick changes from various builders etc.
Rj
 

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Why does the graph compare an unbalanced driveshaft? ...

Pete
 

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question all things being = a stock d/shaft with all the u joints steel and gilbo.. if you put a handle on it and started to turn it over as compared to a 1 piece aluiumn d'/shaft , would not the 1 piece aluiumn d/shaft turn over easyier..? now ad the angle the the stock alfa d/shaft has at the rear part should there be a little more resistance? as compared to a aluiumn d/shaft ?
 

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what is easyer to turn over? a single piece aluiumn d/shaft,with only 2 flex points that weighs in at X pounds or a 2 piece much heavier steel d/shaft with 3 flex points? perhaps I was wrong/ mis typed on hp, yes motor make hp but a heavy steel d/shaft with a gilbo on the front then 2 U joints sucks power... the reason for the alfa set up was smoothness, less vibration( you all know that part.. some of you fit it a lot)
 

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quick question,if a 2 piece steel driveshaft is so great... why, when they can do drivers stuff in a 1 piece aluiumn or carbon fiber drivershaft? a steel 2 piece driveshaft eats of hp/tq.. a light shaft' will not
 

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Some folks need to do some homework on the subject of the 'critical speed' of shafts. Aluminium and carbon composite driveshafts have a higher stiffness to weight ratio than steel, and thus can be designed to have a higher critical speed at any given length than a steel one.
Therefore--it is possible to replace a two piece steel shaft with a one piece in aluminium.
If you reach, or even approach the critical speed (the speed where it whips like a jump rope) of a drive shaft, EXTREMELY ugly (even fugly !!) things can and WILL happen.
If ujoints or support bearings absorbed ANY significant amount of power, they would get unGodly hot !! Just 1 Hp worth of friction generates 2546 Btu/hr. of heat--MORE than enough to get either a U joint or a support bearing WAY hot !! They don't--so--they are NOT absorbing that kind of power.
Im pretty well convinced that Alfa used the guibo in their driveline for two reasons: (1) to get a CV joint at the first joint in the two piece driveline. (2)to provide some torsional shock absorbtion in the driveline so as to make life gentler for a tranny and final drive which are not excessively stout. Shock loadings absolutely produce the highest losds on transmission and final drive gears.
Another issue with guibos, which becomes obvious in racing, is centrifugal expansion (and occasional failure !!) at high rotational speeds.
One more thing while I'm on a roll: Dana Spicer, for one, says NEVER to set driveshafts up so that their U joints are running, steady state, at a deflection angle of LESS than about 1.5 degrees!! This much deflection is necessary in order to move the needles in the joint far enough so that they (1) lubricate themselves (2) do not brinnell themselves into the cross and caps.
IMO spending money for time on an inertial (NON load bearing) dyno is an absolute waste. To quote RJ--'the numbers they generate are crapola !!'
Greg
 
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