carbon fiber driveshaft - Page 3

svxfiles · #31 03-02-2008, 10:18 PM

Quote:

Originally Posted by tubbstcg

When my next paycheck comes in im hoping to get some new wheels tires and brakes

I know where you can get four plated, dimpled, slotted rotors, pads, and stainless steel lines for $375.00.

tubbstcg · #32 03-02-2008, 10:22 PM

Definitely I know where to go on that.

NikFu S. · #33 03-02-2008, 10:31 PM

Quote:

Originally Posted by Myxalplyx

Questions, Questions!!!

Thanks for the stock SVX driveshaft info. Who are you purchasing the $200 driveshaft from? How much does the aluminum driveshaft weigh?

I'm getting it custom made from a place in town. I don't know how much it will weigh. Maybe 15-20lbs? I've been planning it for about 3 years but I've never had a reason until now because I can't use my stock shaft anymore.
This is useful to me as part of a cumulative weight reduction of the car.
No A/C, no trunk junk, fb hood coming later, 5mt w/light flywheel, light wheels, no pass. seat, whatever else I end up doing.

Trevor · #34 03-02-2008, 10:51 PM

Quote:

Originally Posted by sicksubie

a CF driveaft will NOT get you more power to the ground at all. It will not magically reduce the amount of parasitic loss through your driveline. Your car will simply have the ability to rev slightly quicker. Personally look at an aluminum if you have $$ burning a hole in your pocket. I do not see a TON of weight coming off a 2 piece shaft that the svx has stock.

The operative word here is SLIGHTLY. In fact so slight, as to be not practically possible to measure. The engineering has been laid down correctly earlier in the thread.

tubbstcg · #35 03-03-2008, 03:57 AM

about what length of a drive shaft will i need after doing the 5spd swap?

NikFu S. · #36 03-03-2008, 04:15 AM

About 2 inches longer than stock, but you'll want to measure for accuracy.

tubbstcg · #37 03-03-2008, 04:22 AM

k thx alot

cdigerlando · #38 03-03-2008, 05:13 AM

Quote:

Originally Posted by tubbstcg

I was thinking about upgrading when i did the 5spd swap.

Be carful doing this with a manual trans. I know that on my WRX you can only lighten the pully or the flywheel, not both. You get a lot of backfiring. It seems like someone should be able to tune this out, but I don't think anyone has. There is discussion on Nasioc. Perhaps you can post there and see if anyone has discussed this before.

LetItSnow · #39 03-03-2008, 05:21 AM

Quote:

Originally Posted by It's Just Eric

edit: ditto on the wheels and tires. Taking weight off there makes a HUGE diffrence

This could easily begin to venture off-topic, but it should be noted that ANY rotating piece of a car can, in changing mass, have a positive AND/OR negative effect. If a wheel/tire combination is lighter, then it will benefit as unsprung weight (good for the suspension) but if the wheel/tire has a higher moment of inertia, then it could very likely slow the acceleration of the vehicle, as it consumes more energy to spin it up to speed.

Quote:

Originally Posted by tubbstcg

I dont know much about what i am talking about...

Before you begin throwing money at your concern, you should gather an idea of what might be the best solution(s) to the problem. In the long run, a CF driveshaft would be less of a kinetic energy pig than a conventional shaft, but it's a long way out on things that will be beneficial to your car's performance, as it's tremendously unlikely that you'll notice its presence (beyond your wallet).

Myxalplyx · #40 03-03-2008, 05:53 AM

Guys/Gals,

This is what I was driving at earlier. Let's get some pricing info and weight info and let the 'buyer' decide if it is worth it or not. Lots of info here but no data.

As a matter of fact, I would not mind being a guinea pig in this situation. All I want to know is WHO to purchase the driveshaft from, what it weighs and how much it will cost to get done. I will call the shop/manufacturer/person and can go from there. Never was one to argue if it will or will not work. It is lighter. If it is 50% or more lighter than the 35lb stock unit, I will whole heartedly consider it myself. If it is a waste of money. so be it.

Personally, I am happy about the lighter wheels and pulley of the car. This is another small piece to the whole puzzle to wring out as much as possible out of the piggish SVX. Thanks for the NikFu S.

Could you please provide the name of the shop that is the 'place in town' and possibly a number. We can take this offline if you like.

We gotta make some progress with these ideas somehow rather than stifling our imaginations with unproven facts.

Let's move on them and test. You never know until you try.

The link to the article I provided earlier in the thread showed a noticable/measurable difference. It was not much but a difference. The difference between the guys stock driveshaft and a carbon fiber unit was 11lbs. Nikfu is talking at least that much with an aluminum one, let alone a carbon fiber one. Again, people can argue all day over these things. Someone should test this out though. Heres another article to check out-->http://www.acpt.com/article1.html Another driveshaft weight reduction of about 10lbs.

lhopp77 · #41 03-03-2008, 09:35 AM

Again you would probably take off a lot more weight on the car by removing all radio/stereo related equipment.

Of course weight loss is really probably not that important to you.

Lee

svxfiles · #42 03-03-2008, 10:31 AM

Quote:

Originally Posted by lhopp77

Again you would probably take off a lot more weight on the car by removing all radio/stereo related equipment.

Of course weight loss is really probably not that important to you.

Lee

Way ahead of you Lee!

There hasn't been any GOOD music since Jim Morrison faked his death, anyway!

3305#s with a 1/4 tank.

I would rather go with a ONE PIECE alluminum driveshaft after I make more solid the engine and rear diff mount.
The rear is 1/2 way there with the 15 minute mod X three!

Tom

Myxalplyx · #43 03-03-2008, 10:48 AM

Quote:

Originally Posted by lhopp77

Again you would probably take off a lot more weight on the car by removing all radio/stereo related equipment.

Of course weight loss is really probably not that important to you.

Lee

Notice the items I mentioned (Pulley, wheels, driveshaft) is weight loss with rotating mass. No, I am not particularly interested in the typical weight loss. I have no plans on removing anything before making a 1/4 mile run. Spare tires, radios, tools, back seats, etc will all remain inside the vehicle like it normally does.

Because if it is one of the better N/A runs, I want to rub it in like a whole can of Vicks vapor rub, so people can smell my victory after they wake up. **Evil Laugh**

LetItSnow · #44 03-03-2008, 11:33 AM

This sounds like another trampoline shot to the moon, to me. There's no sound math behind it.

Regarding the pulley, consider how the mass is magnified after the transaxle gearing, and how the pulley's reduced mass winds up lost and negligible in all of that.

Regarding the CF driveshaft... I'm not sure about the return which may be as steep as $300/hp.

Kevin, your first link shows the car to actually be slower, two out of three, in the 1/8 mile. It also makes some pretty questionable claims. The second one incorrectly uses the formula for MOI (it doesn't function at the OD!) I'm interested in seeing some credible claims from sources who use correct scientific method and proper physics, if they're going to use any.

svxfiles · #45 03-03-2008, 11:34 AM

Quote:

Originally Posted by Myxalplyx

No, I am not particularly interested in the typical weight loss.
Spare tires,**Evil Laugh**

Me neither!

Spare tire is in the drivers seat!

Thanks, Kevin, now I feel bad about myself.