Unitrax Lightweight Half Shafts - Anyone using them?

[Big E]

I cannot seem to make up my mind. I done some searches here and it still isn't helping me decide. The "regular" Unitrax half shafts can hold up to 800hp. But the lightweight ones look to be about 7 pounds lighter (for the pair) and apparently are good for over 800hp. I don't plan on going much over 600 with a S/C but I want to use drag radials whenever I go to the strip (yea probably the street too ).

Any suggestions?

Thanks.

 

[SUN RA KAT]

OT - Removed.

 

[Joseph Dell]

RE: half-shafts - go w/ the "heavy duty" 800hp ones. the others are nice, but at double the price they ain't worth it. I'll have a set of barely used titanium (whatever the 1000rwhp) ones forsale in a few weeks... but for you, the 800hp ones are more than fine.

JD

 

[Bugeater]

Curious - do you lose 7 pounds each?

Isnt weight lost in the driveline (driveshaft, halfshafts) worth the most in terms of performance over all other weight reduction methods...

Someone know what the "formula" is for every pound out of the driveline vs. other areas of reduction? Unsprung weight etc...

 

[Big E]

Thanks JD for the input. That is what I kind of wanting to hear. BTW, why are you going to get rid of the titanium ones?

Bugeater, I was looking at the shipping weight out on the Roe website. It was 7 pounds total. I'm suprised it was only a 7 pound diffrence.

I've read a little about weight reduction in general. A reduction of 100 pounds (sprung weight) will lower the quarter mile ET by .1 second on average. It would probably be better (for me anyway) if I lost some weight.

Thanks all!

 

[Joseph Dell]

Thanks JD for the input. That is what I kind of wanting to hear. BTW, why are you going to get rid of the titanium ones?

Moving to a different rear end set-up that doesn't use these types of half shafts.

 

[kwkshift]

Curious - do you lose 7 pounds each?

Isnt weight lost in the driveline (driveshaft, halfshafts) worth the most in terms of performance over all other weight reduction methods...

Someone know what the "formula" is for every pound out of the driveline vs. other areas of reduction? Unsprung weight etc...

Sort of. The key to picking up performance with reducing weight on anthing that reciprocates is its diameter or moment of axis, (I believe that's the term, one of you physics guys can correct me). Basically, the larger the diameter of the mass, the greater the difference it makes.

I had the formula somewhere, but I can't find it right now. Basically, as an example, removing 6 lbs. from a mass with a 12" radius is worth way more than removing 12 lbs. from a mass with a 6" radius. The only real driveline mod that would provide the most performance gain would be light weight wheels. For something like a halfshaft or driveshaft, there is no gain because they aren't a large enough diameter.

Hell, my car didn't lose any power when I went from an aluminum flywheel to a steel one.

 

[Bugeater]

Thats an interesting comment because I have heard from others (typically in the roadracing areas of interest) that driveshaft weight reduction is one of the best areas to drop from - better than wheels...

Is the formula also a function of rpm as well as diameter? Also, I imagine a carbon fiber driveshaft would be lighter and potentially a smaller diameter than stock.