aluminum driveshaft

[DriFt3r]

was thinking about getting this...how much power will this driveshaft free?

[I am Technoman]

Well the drive shaft you have now is a two piece one and is somewhat heavy so if you get a lighter one piece it will allow more torque and more HP at the wheels. I want one damit!

[WDRacing]

You need one once you get into the 10's anyway....lol. Lighter rotational mass is always a good thing. Not to mention the lighter vehicle in general.

WD

[mrniceguy]

who sells em

[EastCoast240]

Enjuku

[LT_Z]

Do you know if they make one for 89 RPS13 ?

[Structure240sx]

yes they do i want one too

[andrave]

lighter rotational mass isn't "always" a good thing, especially in drag racing. rotational mass, especially the flywheel, stores up energy that is released when you drop the clutch. too light of a flywheel and you car is much more likely to bog on the starting line, which makes it more difficult to launch. Same with the crank.

[WDRacing]

A ultra light rotational mass means the shifting has to be done without error and real fast, like when drag racing. The lighter rotational mass will be able to rev a ton higher, but as soon as the clutch is engaged, the rpms will drop alot quicker then with say a heavier flywheel. Using a lightened crank, lightened meaning only 3lbs or so removed at max is fine. Cause it needs to be knife edged vey badly. If your not going with titanium rods then you don't have to worry about what rods you pick. Pistons aswell. The flywheel is like 28lbs or so stock, far to heavy, so one that cuts down to 15 would help the revibility as well as allow for the turbine to come on boost without so much lag do to paracitic loss. And finally, NO ONE in drag racing should use stoc driveline componants. Your average car that can't get deep into the 13's is fine, but for all else, if you have the money, a D/S swap isn't a bad idea if you do alot of drag. Also, get a D/S loop installed at the same time.

As far as launching goes, you need to slip the clutch alot more or drop it from a bit higher then normal. But it isn't all that hard to figure out with some practice.

WD

[Structure240sx]

thanks WD i just ordered my fidanza flywheel and ill be doin mainly drag racing and got worried after reading what andrave said.

[andrave]

I think the fidanza is still heavy enough to store some power off the line. I didn't say that you don't want a light flywheel... just that you don't want too light of a flywheel.

Also, I believe the new rules for one of the sanctioning bodies call for scatter shields and DS loops for any car quicker than 13.99 now. Whatever you go with, if you are making power, a DS loop is CHEAP insurance. They aren't that much and dropping a DS is never pretty.

[Structure240sx]

can u explain to me a DS (driveshaft right) loop and scatter shield. im guessing the scatter shield is for the flywheel maybe. if that rule is tru ill be needing it my car should be in the mid 13's til after the winter

[andrave]

NHRA rules as quoted from "SFI or die" from the october issue of drag sport (please note that that "NDRA, NHRA, and IDRC safety requirements are all similar. However, the rulebooks from each organization will detail the specific class requirements for competition").

"13.99-12.00 Seconds

Driveshaft loop. IF you have a rear or all wheel drive car which is running 13.00 or quicker, an NHRA accepted driveshaft loop installed within six inches of the front U joint is a must. If you're running slicks, the rules are enforced for 13.99 seconds and quicker. The driveshaft loop protects the driver and vehicle from serious injury and damage in the even of a broken U joint or shaft.

11.99-11.00 seconds

Flywheel and Clutch: The flywheel must meet SFI spec 1.1, 1.2, or 1.3. No cast iron flywheels or pressure plates are allowed. If a slider clutch is used, it must meet SFI spec 1.2, 1.3, or 1.4.

Flywheel shield. All vehicles equipped with a mnaual tranmission are required to have a flywheel shield (bellhousing) meeting SFI Spec 6.1 (single disc clutch) or 6.2 (multi disc clutch). Cars w/rotary engine must have a flywheel shield made of 1/4" minimum steel around the bellhousing 360 degrees. The NHRA allows the use of approved shield designed for a different application when one is not available for a particular vehicle.

10.99-10.00 Seconds

Axles/C clip: Aftermarket forged alloy, high strength axles are mandatory on cars running 10.99 or quicker. Any vehicle with a locked or spool rearened also requires aftermarket axles, regardless of elapsed times. Positive axle retentino device also required (no factory C clip style axles are permitted). Harmonic balancer: Factory cast iron harmonic balancers are not permitted. Only units meeting SFI spec 18.1 are legal. "

Please not that I was incorrect above, DS loop is only for 13.00 and quicker, and scatter sheild is even faster. Also there are many other requirements, I just tried to give the drivetrain ones since that is what is pertinent to our discussion/

[LT_Z]

Dood where can i find more info on requirements for low 10's. And where the hell am i going to get aftermarket axles ?

[Structure240sx]

i wont have to worry about 10's until the next car i build maybe

[WDRacing]

Things differ from racing in a sport and just hitting the track occasionally. Each track has different rules for most speeds. The Drag rules are more stringent as far as safety goes because its a sport, the vehicles are only track cars and not daily driven.

If I had a stock flywheel, I'd get a scatter shield. With a nice forged FW, its just added weight. The DS loop is a must if you drag.And once you get into the 12.s your gonna want good driveshafts and axels anyway.

WD

[LT_Z]

WD hey do you know of any axles ? or do they have to be custom ? or what ?

[andrave]

yeah I've seen a couple guys break axles but haven't seen any aftermarket performance ones... where are they?

[Nathan]

I keep going back and forth between the stock flywheel and a Fidanza...with 300+ hp I'd really like to go with a lighter flywheel and the replaceable friction surface is nice since I've seen ACT 6 puck clutches like mine eat flywheels before. But the stock flywheel just looks so big heavy and sturdy and the Fidanza is aluminum which just seems like an evil metal to me (yeah I know I have forged aluminum pistons...I've resigned myself to that). Does anyone know if the Fidanza is sturdier or weaker than the stock flywheel? I like my feet/lower legs where they are...

[WDRacing]

Forged aluminum flywheels are great...period.

No idea who makes axles for our cars, might have to have a set custom made.

WD

[Nathan]

Grr, looks like it's credit card time! woohoo for impending debt!

[LT_Z]

I wonder if anyone makes a scattershield for s13 trans/flywheel.

[andrave]

summitracing used to carry a few scatter shields, maybe someone should give them a call. As for axles I'm guessing any place that makes aftermarket axles could probably help us out, someplace like prodrive or curry enterprises, its just that they are gonna be $$!!

[C-Kwik]

lighter rotational mass isn't "always" a good thing, especially in drag racing. rotational mass, especially the flywheel, stores up energy that is released when you drop the clutch. too light of a flywheel and you car is much more likely to bog on the starting line, which makes it more difficult to launch. Same with the crank.

This doesn't apply to a driveshaft since energy can't be 'stored' in the driveshaft prior to launch. A heavier driveshaft would in fact work against a good launch since it requires more energy to get a heavier object moving.

[C-Kwik]

Driveshaft loop. IF you have a rear or all wheel drive car which is running 13.00 or quicker, an NHRA accepted driveshaft loop installed within six inches of the front U joint is a must. If you're running slicks, the rules are enforced for 13.99 seconds and quicker. The driveshaft loop protects the driver and vehicle from serious injury and damage in the even of a broken U joint or shaft.

It also limits the possibility of your car doing a pole vault if the front of the driveshaft breaks and it digs into the ground.

[LT_Z]

HaHa pole vault, I agree about the rotational mass of the driveline, in that it would help the launch. Im thinking the stock flywheel would actually "hit" harder on the launch but the lightened flywheel would rev way faster the rest of the way, and in the end you wind up way higer in RPM in your finishing gear which , makes me think you would be higher in MPH, which is always nice

[andrave]

I didn't say a lighter driveshaft would hurt you on the launch. Read more closely, I said crank and flywheel. A lighter driveshaft WOULD help your launch.

[C-Kwik]

I didn't say you did. But you didn't say you didn't in the post I responded to. I posted merely to make sure others understand this and don't assume what you said applies to the drivesahft.

In my line of work many of the things you don't tell a person ends up being what they misunderstand the most. I have a habit of thinking of the bigger picture.

[andrave]

OK, sorry, I didn't know I was so vague in the first post. I was just trying to make the point that sometimes the lightest rotational mass isn't always ideal. I know that a lot of the guys on this forum are into drag racing and I know several import racers that try and leave a heavier crank and flywheel setup on their cars for a better launch.