Well thats my question, if you have one...could you feel the difference?

 

The only difference I noticed is the lack of vibration at +100mph speeds.

I'm running 4:10 gears so 100+ is really spinning that driveshaft!

As for a notice in performance or better 1/4 times.... none.

 

I am of the same opinion, that the alum driveshaft probably did NOT help my 1/4 mile times much if anything noticable. More than likely where the benefit would come from is the fact that it has better balancing, and would vibrate less. When you get vibrations in your drivetrain you loose power because the energy is absorbed into the vibration rather than transfering the power to the rear wheels.

John

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G O D BLESS AMERICA
87 Formula Yellow/Black

5.1 TPI Automatic
Baer 12" brakes 4 wheels, KYB AGX Adjustable Shocks & struts, Custom Leather interior, WAAAY TOO MANY MODS TO LIST

87 Formula TPI (5 Speed) Yellow/Gray STOCK

1967 Buick Riviera 430hp Turns high 14's (Not bad for 4300 lbs)

83 Camaro
83 T/A

http://www.3rdgenformula.com

 

I think it helped a little, it weighs less, as mentioned before, its balanced better, having it weigh less means the engine has to turn less weigh so you won't be loosing as much power(which probly isn't a WHOLE lot..)

 

Even though the aluminum shaft only weighs a little less than the stock shaft, when you rotate a mass at high speed, it creates weight. I forget but for every pound of "rotating" mass you reduce, you mulitply the weight by like 8. So lightweight drag skinnies are a big savings at the track. Same thing with light-weight flywheels, aluminum brake drums etc. I can tell the difference in my 92 Z28 convt 5spd when I have the aluminum shaft in vice the steel one. The reduced mass allows the engine to spool up faster etc. I firmly believe it's a worthwhile modification.

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Rob P
89RSconvtZZ4TPI Edelbrock Intake
SLP Dual Cold Air Intake 1 5/8" Headers Semi-Siamesed Runners, IROC
suspension, alum shaft. Numerous mods.
92Z28convt5spd (stock)
71Impala convt 402BB
BETTER DRIVING THRU SUPERIOR HORSEPOWER!

 

Velocity = Inertia x Radius (V=IR) is the equation for a rotational mass. Mass is a component of Intertia; therefore to keep the equation constant as mass increases then velocity must increase to maintain the same rotational speed. Lighter driveshaft results in less work the engine must do to produce the same rotational velocity. Any savings in HP loss between the engine and rear wheels is a plus. Look on E-bay. One sold last week for $100.00.

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87 TA, 305 TPI, Custom CAI, ACCEL 8mm wires,ACCEL Super-coil, ACCEL Plugs, JET TPI Airfoil, Cherry Bomb Muffler
"35 yr old helo pilot
with a cool new toy my 17 yr old son wants"
The Phoenix Project..click to see my project car

 

I'm unsure how much stock driveshafts' weigh on your vehicle but it will be less rotating weight and also it will definately help with vibration issues.

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Founder, Tealnet.Com

'98 Mustang GT

My 98 GT

Mods: Vortech S trim, 42# inj, 5.4 Heads (ported/polished), custom ground cams, 99 intake, ATI 3 corer intercooler, Walbro 255 intank pump, Walbro 255 inline pump, Aeromotive adjustable fuel pressure regulator #13102, NO FMU!, Steeda Tri-Ax shifter, Steeda heavy duty LCA's, Steeda heavy duty UCA's, Steeda Chrome Moly subframes w/cross-brace, Steeda Cobra R hood (2 1/2" cowl), BBK 75mm TB, Pro M 80mm MAF, Eibach progressive springs, K&N Air, Cobra "R" rims, 31 spline Moser axles, SVO differential, Downs rear Girdle, FMS 3.73 gears, Cobra floor mats, Cobra leather shift ****, "A" pillar (Phantom White Gauges and custom gauge pod), Steeda race pedals, Mac offroad "H" pipe, hi-flo cats, and Borla XR1 catback.

Dyno #'s: 298.2rwhp/332.8rwtq (running rich 9:1 a/f)

Best ET to date: 13.42@104.91 (Temp F: 109 Humidity: 38 Barometer: 28.90) See the run on video!

Mods not installed: 3 core intercooler, ditching the FMU!

 

besides the less rotating mass and being better balanced it looks cool when you work underneath the car

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86',88',89' IROC-Z, 350 TPI, 700-R4

94' Formula, LT1, 6spd

 

It took a vortech s trim to go 13.4 in a mudstain? I wish I had two cams.

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1991 Firebird
350 L98 (was a 305 TBI),T-5,Edelbrock TES and cat back,Accel manifold
NOS,subframes,jegster torque arm,MSD Digital 6
AFPR,Lakewood lcas
Hurst linelock,SLP cam (206 212 .480 .486),relocated battery,cold air,Hypertech chip,centerforce df,clutch
poly bushings and mounts
AFR 190s
Harland sharp 1.5 rockers
autopower rollbar

12.33 @ 114.83 juiced uncorrected

13.510 @ 102 non juiced uncorrected

 

Everybody talks a lot of smack about rotational mass. In accordance with conventional driveshaft engineering equations (I don't have my book with me, might be tau=Tc/J) the radius must increase due to the decreased stregth of aluminum.Somebody post the equation if you know it.

Therefore, by the equation for mass moment of inertia about the x axis, Ixx = Sum (mass)(r^2). Notice how the moment of inertia is more affected by radius than mass. Therefore, depending on the dimensions of the driveshaft, you might be doing more harm than good.

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355 c.i.
Dart 180 Heads
Lunati 224/224 cam
Harland Sharp 1.5 rockers
Performer RPM Manifold
Holley 600 cfm double pumper
Hooker Super Competition Headers
Flowmaster Exhaust
Competition Engineering Sub-frame connectors
Super T-10
GM posi 3.42 rear
Hurst Roll Control
13.9@102

 

I have a TPIS aluminum driveshaft that I got off of a friends '96 TA. After running both at the track (similar weather conditions), I noticed no gain in performance. The aluminum driveshaft's diameter is 3.5" vs the stock one's 2.75(?). Vibrations are a little better with the AL shaft(but not much).

Definitely not worth the $300+ dollars he payed for it. I got it from him for $100, otherwise, I would have put my old one back in.

Sparks a flyin'