Staples

iTrader: (9)

The reason why there were 16 run differences was because they took the highest dyno with the stock driveshaft, pulled the car off and put another one up and was tuning it in the mean time under the same run file basically (it was a forced induction car). Once the driveshaft was installed, they put it back up on the dyno and did about 2 - 3 runs and took the highest gain off of the Z1 driveshaft.

I hope that clears the misunderstanding up.

TVPostSound

iTrader: (9)

Middle school grammar!

G37Sam

Exactly, and my point is, the costs are pretty similar. When building a car on a corporate level, it's mostly a combination of safety, performance and price. We all know you can't have all three combined.

And that's why I'm asking, if Nissan Engineers saw the Al Driveshaft as being somewhat similar in price, with added performance and safety, you don't think they would've considered that? Instead of opting for a more complex two piece Steel drive shaft

Come on BB, the price difference between an OEM DS and the AL DS is negligable. The price difference between a 7-speed AT and a DCT would be insane. They're not very comparable.

Micron

We need a more analytical approach... Same number of runs for each DS, remove the highest and lowest to better account for anomalies and then average the remaining runs.

If the gains were to be had from the reduced weight, but still address the issues such as geometry, whip, etc... why not just go multi-piece with lighter materials?

The weight loss may not be as significant as a single-piece, but Sam's logic comes across as rather sound... with the prices being so similar, why would they choose the multi-piece over a single-piece?

soundmike

iTrader: (6)

Basically, the after #'s included the gains made from the tune as well?

SharpByCoop

Staples: Most tuners have specific folders for each car. If what you are saying is that the MIDDLE runs between 048 and 064 were still in the 'G35' tuning folder, then those were from another car entirely? That makes sense, but it's a source of confusion.

When I go back to the dyno again at The Shop, my next run will be one digit higher than my last run, even if it was a year ago. He will start with my folder and file name.

See why I would call this?

Coop

Black Betty

iTrader: (60)

Read what you quoted again Mike. The tune was being done on another car (i.e. not the one getting the shaft installed). Stop confusing us even more!

I can see that the explanation Staples gave is very plausible. While it would be great to have only runs from one specific vehicle in a given folder like Coop said, every shop might not do it this way. Or perhaps a tech simply overlooked it and started doing tuning runs without changing it on the computer after the drive shaft install. Then when the drive shaft car got back on the dyno after the install, there had been 16 runs done in the interim. I don't know if that's the case, but it's plausible.

At any rate, I like the area under the curve on the torque number through the powerband. If that's reasonably accurate, it's dead sexy. Hopefully we will get more and more reports form users in the coming months. Thanks for sharing results. And keep the info flowing guys.

Black Betty

iTrader: (60)

Becasue every dollar counts. If the difference is only $50 per unit in materials, think how much much money you are talking about. Hundreds of thousands of dollars when taking into account every unit sold. It's all about P&L in the end. If they did this they'd have to raise the price of the car accordingly. There will always be performance compromises to reach a specific price point that their research has shown the market will pay for a given car. If they didn't cut performance corners and made a better car that cost $65K, consumers would complain and say, "I could buy an M3 for that money!"

Because multi piece aluminum reduces the weight savings and therefore reduces the gains seen. If the gains are not significant, it's not worth it. Not a lot of people are buying it now. If it were heavier and returned less power and torque gains, the community would be criticizing it because it didn't deliver enough bang for the buck.

As far as the data you want, you are asking some guy who has the drive shaft has to spend a bunch of extra money out of his pocket doing a bunch of dyno runs for the benefit of the community. I probably wouldn't be willing to do that myself. Would you?

If you think that's a better way to get data on it, are you willing to contribute into a fund to pay for all those dyno runs? If all of those interested in the data you think is necessary all put in a small amount and a respected and trustworthy member of the G community who is buying the part were willing to do it and post detailed results, it might be worthwhile. But if it's just a matter of wanting someone to fund all the research themselves and post it up, you might find a philanthropist to do it, but not likely.

If anything you think the manufacturer/vendor might pony up the money for something like this and reimburse an independent user for the extra dyno runs to substantiate the gains and use it to sell more shafts. But most of them don't think this way.

ANMVQ

iTrader: (13)

Well we can forget the X talk, Just spoke to them again and they said the end of the driveshaft is diffent.. so Again us X guys get the "SHAFT" ,, LOL

Legz

iTrader: (1)

boooo sucks, but if there's enough interest maybe they'll make one.

G37Sam

BB, if you want to convince yourself to buy it then you don't have to convince me

A steel drive shaft is more R&D time since its a two piece with an additional u-joint. If Nissan engineers opted to use AL drive shafts on their entire lineup you don't think the price of that would drop? It would be very much worth it in terms of ROI. How hard do you think it is to manufacture a single piece driveshaft?

Modme

iTrader: (17)

at the admins.


I think its a combination of cost reduction and noise reduction. As stated earlier, one piece drive shaft will increase Noise, Vibration, and Harshness (NVH). The Infiniti car line is catered towards people who want a combination of performance and luxury. Noise and vibration reduction is a priority. Therefore, a two piece drive shaft is used.

On the other hand, 370z is more performance oriented. There is much less sound dampening throughout the car and also has a one piece drive shaft. The road noise and vibration is significantly higher than a G37. Many G owners would turn away if the G drove and sounded like a Z.

Modme

iTrader: (17)

In terms of reliability and durability of the Z1 drive shaft, only time will tell. Any vibration is bad for your drivetrain. A failed drive shaft can do a lot of damage.

Staples

iTrader: (9)

A major reason why they used a 2 piece drive shaft as well is because of safety hazards. If you were to get into an accident, a 2 piece would have a tendency to bow a little at the joints. On a 1 piece, it can snap and enter the cockpit (unlikely, but could be a lawsuit waiting to happen). That's also why they use a carbon fiber driveshaft in the 350 / 370z. One for performance, two for safety.

Emillion45

Of course. Looks like I'll have one custom fabricated.