Yes!!

 

I'm in on this, e-mail sent. Come on we need 21 more.

 

The shipping is free at the group buy price as long as it is in the continental US.

 

i wouldnt mind getting in on this, but am i right the savings is only $50 plus shipping?

i need to divy up my tax dollars before i can commit to this though

 

How many ponies does this free up for the wheels?
Only $50 savings off regular retail?

 

Put me down for one with the adapter plate!!

I'm still overseas, but I might as well get in on a good deal too! If this were the 4" shaft i wouldn't be doing it, but for a 3.5" it's worth it....

 

I have an automatic 05 GT.

I've heard about vibration issues with automatics and most people here are probably purchasing for manual transmissions.

Will this shaft be OK for automatics?

I want real evidence for this not just speculation.

 

While I can't speak directly about the Shaftmasters driveshaft on a automatic I do have the competitions driveshaft on my automatic and have absolutely no issues with vibration. Hope this helps!
Scott

 

Here is some info from a forum on rotation weight. Warning science and math to follow...

My quick calculations (odds are not 100% perfect but close)
Stock DS (43lbs)= .597 ft/lbs
Shaft Masters DS (17lbs)= .181 ft/lbs
this is the inertia that the engine must over come just to start the DS rotating, and the higher the RPMs the more HP from the engine is required to rotate the DS.

Here is a link on the physics of rotation weight
http://dev.physicslab.org/Document.a...arMomentum.xml


this is from another car forum
*************************
Ok.. So you hit a sore spot.... physics... Open your minds brothers...

I read that whole article... and yes.. it is all very very true. But only one underlying factor.... no calculations for you to see exactly how much force changes when you actually increase or desrease the weight and or size of the wheel.... I'll show you...

Moment of Inertia - The property of an object associated with its resistance to rotation. It depends on the objects mass and the distribution of mass with respect to the axis of rotation.


Basic Rotational Inertia formula. I= ½ MR2 (2 = squared)
I= Moment of Inertia... M = mass and R = radius of the wheel.

So... lets take a 20 pound wheel... 17 inch.. (I'll work in SI units)

I= .5x(9.0718474)x(0.4318/2)>2 (>2 means squared)
I= .959040098 kg/m>2

The same equation for a 15 pound wheel that is 17inches...

I=.5x(6.8038856)x(.4318/2)>2
I= .539460063 kg/m>2

Just for clarity.. the next exp. is the same two wheels being pushed by 200 HP. ( Its not exactly right because I'm not taking in acount for the weight of the car.. but this should demostrate how much the weight of the wheel actually plays in acceleration of the car..)

Ok.. still speaking of a 17 in. wheel here...
Equation for torque being applied to both wheels is: Force times the Radius:
BTW 200HP is equal to 529559102.065818 Newtons

t = Fr = (529559102.065818N) x (.4318/2)= 114331810.1
This torque value is a constant... because it is just showing how much force is applied.

AND finally... when you take the Torque.. or Force being applied to each wheel.. and DIVIDE it by the moment of inertia.. which I remind you is the resistance to rotation. You get.....

20lb Wheel : I/t = (114331810.1)/(114331810.1) = 119214838.2 rad/sec>2
15lb Wheel : I/t = (.539460063)/(114331810.1 ) = 562500008.2 rad/sec>2

Ok... So.. now your wondering what the hell I've found with these numbers... well after another converstion from radians per second squared.. to RPMs... I get..

20lb Wheel : 5270.45301489 RPMs
15lb Wheel : 24867.9603047 RPMs

Both of those numbers clearly demonstrat... that with less weight you can speed that wheel up faster... an almost 2000 RPM increase due to 5 lbs of weight.

So... in short... lol... it takes

This is how much HP it takes to move each wheel....

20lb = 0.13039 horsepower
15lb = 0.07335 horsepower

As you can see... the 15lb wheel... takes less horse power to move..
***************************


Re: Revolutions per minute to Radians per second
by Wilfred on 10/07/05 at 20:46:52

 

yea so, i couldnt stand to read any of that physics stuff......

but less weight is better, more freed up HP to the wheels, and more pucker for the butt dyno!!!!

thats all the rationale that i need

 

I've got an automatic plus I'm lowered and I have no vibration issues with my 3.5" Shaftmaster DS.

 

Did you get the one with the adapter ?

How does it compare with Spydershaft ?

 

Yup I got the one with the adapter. I never had a Sypdershaft so I wouldn't know.

 

If I don't mind changing out the pinion flange, shouldn't I go without the adapter and get the new pinion flange? It's just one less point of failure that way, no? Again, assuming I don't mind changing the pinion flange.

 

That is fine with us, as long as you are confident in changing the flange. I currently have five shafts built and am working on more right now. I am going to try and have enough built by the time we finish receiving 25 orders so they can ship out without any delays.

Robert

 

Any members that have posted on this thread that they are in for the group buy have been added to the list. However, it would be nice if from here on out memebers could follow the instructions and email me.
david@shaftmasters.com

thanks, David

 

What kind of HP will the DS handle? I plan on adding a KB SC sometime this year.

 

We have customers who are using these shafts that are pushing over 500 hp.

 

will it handle 600 or 700hp?

 

Rated at 8044 RPM 1/2 Critical Speed and 5036 FT-LB Torsional Yeild