I don't know the weight of the stock Porsche wheels. But if we assume that there is a plausible weight reduction of 50-60 Lbs from the combined four wheels, i think a 0-60 mph improvement of one to two tenths of a second is entirely possible. This is due to the combined effects of mass (weight) and rotational inertia.
Of course, any really lightweight forged alloy wheel would have a similar effect on performance if the weights and moment of inertia were the same (or similar) as the carbon fiber wheels.

 

True magnesium cast one piece wheels can leak too..... the metal has very high porosity. One of the reasons it is very light. Cars sitting on these wheels for awhile will slowly leak down. Sometimes not so slowly.......... They are not as trouble free as you would hope for, even for the expense.

In general the average person is better off with aluminum alloy wheels as stated many times on this forum. That being said on the track you need the lightest wheel possible and you spend what it takes and put up with the inconveniences as long as they don't compromise safety.

 

I'm very average and love my Dymags. No issues whatsoever - maybe just lucky.


My 500th post

 

Cast magnesium is seldom used in wheels today. More common is forged magnesium which does not suffer from the porosity problems you describe.
However, Magnesium has other properties that make it less desirable than forged aluminum, cost among them.

 

How much more HP would be needed to decrease the 0-60 by 2/10 of a second?

 

It would take 25 to 30 as an estimate. But there are many factors that effect this such as gear ratio, vehicle weight, coefficient of drag, tire grip, etc.

 

I have Dymags and acceleration is the same as with OEM wheels I made several tests at the track with another identical car different color only jiji
BUT when you want to brake to reduce speed you can REALLY feel the difference,bracking is 100% better with lightweight wheels.
Handling hmmm maybe the same as OEM.

 

As I said before, there are lots of variables. On a car like the 997TT that is traction limited, you won't see any 0-60 benefit because the car already accelerates as quick as the tires will permit, due to software/hardware intervention. Increasing grip improves acceleration in its own right, providing there is enough power.
In the end, there are simple laws of physics at work here. Reduce the mass and the rotational inertia and the car MUST accelerate quicker, unless there are other systems at work to prevent it.

 

Interesting

 

In some ways it looks like traction really had become the rate limiting step. Think about how 0-60 times have struggled. Massive increase in HP and 4 wheel drive have resulted in mid 3 sec times. RWD maybe mid 4's. Formula 1 cars with greatly exaggerated power to weight, and very sticky tires are in the mid 2's. My guess is 0-60 times and 1/4 times are going to plateau given the need for street tires to 1) last, and 2) work in the wet.

Major performance gains however can occur in braking and handling with weight loss.

 

In addition, the cars are more responsive and accelerate harder in the 50-100 mph range where the cars are not traction limited. This is a sweet spot for driving for most guys anyway.

 

Should be no blemishes outta the box for the $.

If there are other issues along the way, hopefully they're dealt with quickly and efficiently. <thumbup>

 

I think the Dymags weigh 19lbs front to 20.5lbs rear. The stock wheels weigh 24lbs front and 26lbs rear (without tires). At best, you get a 23lb weight reduction and that is a huge benifit.

 

20.5lbs is correct for the Dymag rears, however the fronts come in at 16.8lbs

A 25.4lbs reduction.

 

Rears 20.5



Front 16.8



Both with valve stems but no TPMS