New wheels by JUBU

[VL3X]

I have been working with Brixton wheels to order the rims on the Ferrari. They said they would weigh 20lbs. I think that is 5lbs lighter than the stock rims. I'm not super knowledgeable about unsprung wheel weight. Is 5lbs alot in this department?

RAYS Engineering stated for every 2.2lbs of weight eliminated from unsprung weight is equal to eliminating 33lbs of overall vehicle weight that your suspension has to manage. So, 5 x 33 x 4 = 660lbs of reduced weight off suspension.

Now I'm sure this formula isn't 100% accurate, but close enough for you to imagine the difference between driving alone in your Ferrari versus driving with 3-4 friends somehow crammed in and weighing it down.

*edit: I suck at math

 

[lion shf]

I've personally never been able to tell the difference in feel on the road -- but some say they can feel it.

Hey I’m not Mario but the TT oems are 29lbs. I replaced them with 22lbs 18” neuspeeds week 1 and replaced the front brakes with a 4 355 stop tech bbk. I 100% felt the difference in my car.

 

[lion shf]

VL3X if you don’t bring your car here within 24 hours of picking it up, I’m gonna freak out
also if you need a ride to Summit I’m your guy I miss my Hopat bros so much

 

[VL3X]

VL3X if you don’t bring your car here within 24 hours of picking it up, I’m gonna freak out
also if you need a ride to Summit I’m your guy I miss my Hopat bros so much

At this point, I'll be genuinely surprised if I actually take delivery. The way things are going, it's not looking good.

 

[Eagle7]

RAYS Engineering stated for every 2.2lbs of weight eliminated from unsprung weight is equal to eliminating 33lbs of overall vehicle weight that your suspension has to manage. So, 5 x 33 x 4 = 660lbs of reduced weight off suspension.

Now I'm sure this formula isn't 100% accurate, but close enough for you to imagine the difference between driving alone in your Ferrari versus driving with 3-4 friends somehow crammed in and weighing it down.

You mis-calculated. If the effect of removing 2.2 lbs of unsprung rotating weight (URW) equals the effect of removing 33 lbs of static weight, then for 4 wheels it would be 33 x 4 = 132. Removing 4.4 lbs of URW would be like removing 66 lbs of static weight, so 66 x 4 wheels = 264 lbs. Removing 5 lbs of URW per wheel is essentially like removing 4.4, so basically it's the difference of having a passenger who weighs in the mid-200's in the car, and then getting out.

Depending on how much power you have, and how much the vehicle weighs to begin with, the effect of removing the weight will be more noticeable on lighter cars. Taking 250 lbs out of an SUV that already weighs 4,500 lbs isn't going to make much of a difference. Take that same 250 out of a car that weighs 3,200, and you'll notice it.

It's a different effect from adding power. When you add power, you feel it in how it pushes you back in the seat. Removing URW doesn't feel more powerful, it just feels like the car moves forward easier, like there's less resistance.

 

[TomE]

Or as Colin Chapman said: adding power makes you faster on the straights, removing weight makes you faster everywhere.

 

[Green]

Thanks for the education I was truly clueless. More benefit than I could of imagined. They offered me a discount If I order and agree to a photo shoot for their website. 8 weeks production so I will have rims before the car

 

[hagen111]

RAYS Engineering stated for every 2.2lbs of weight eliminated from unsprung weight is equal to eliminating 33lbs of overall vehicle weight that your suspension has to manage. So, 5 x 33 x 4 = 660lbs of reduced weight off suspension.

Now I'm sure this formula isn't 100% accurate, but close enough for you to imagine the difference between driving alone in your Ferrari versus driving with 3-4 friends somehow crammed in and weighing it down.

*edit: I suck at math

Sure the suspension will feel less weight in terms of unsprung wheight, but the REALLY BIG IMPACT of saving on wheel weight is down to the force needed for high spinning wheels to change their direction! A wheel spinning at high rpm feels like a block of concrete when trying to change its course either through steering input or to just move them side ways.

Try the following: take a bicycle wheel, extend one side of the axle...hold it on one side and spin the wheel hard...hold it in one hand in front of you and try to steer...you need to be strong! Imagine the wheel being much heavier and spinning at much higher rpm...

Now you also can understand why a MotoGP motorcycle has the cranck relatively high positioned as close as possible to the center of gravity and sometimes spinning backwards.

 

[Porter]

Sure the suspension will feel less weight in terms of unsprung wheight, but the REALLY BIG IMPACT of saving on wheel weight is down to the force needed for high spinning wheels to change their direction! A wheel spinning at high rpm feels like a block of concrete when trying to change its course either through steering input or to just move them side ways.

Try the following: take a bicycle wheel, extend on side of the axle...hold it on one side and spin the wheel hard...hold it in one hand in front of you and try to steer...you need to be strong! Imagine the wheel being much heavier and spinning at much higher rpm...

Now you also can understand why a MotoGP motorcycle has the cranck relatively high positioned as close as possible to the center of gravity and sometimes spinning backwards.

Gyroscopic effect. It's one of the most powerful (and most poorly understood) phenomena in physics.

 

[hagen111]

You mis-calculated. If the effect of removing 2.2 lbs of unsprung rotating weight (URW) equals the effect of removing 33 lbs of static weight, then for 4 wheels it would be 33 x 4 = 132. Removing 4.4 lbs of URW would be like removing 66 lbs of static weight, so 66 x 4 wheels = 264 lbs. Removing 5 lbs of URW per wheel is essentially like removing 4.4, so basically it's the difference of having a passenger who weighs in the mid-200's in the car, and then getting out.

Depending on how much power you have, and how much the vehicle weighs to begin with, the effect of removing the weight will be more noticeable on lighter cars. Taking 250 lbs out of an SUV that already weighs 4,500 lbs isn't going to make much of a difference. Take that same 250 out of a car that weighs 3,200, and you'll notice it.

It's a different effect from adding power. When you add power, you feel it in how it pushes you back in the seat. Removing URW doesn't feel more powerful, it just feels like the car moves forward easier, like there's less resistance.

With regards of reducing weight. Lowering weight as far as possible away from the center of gravity or roll axis has effect! Putting in a carbon lighter seat helps, but not so much. Hence carbon roofs on BMW M-cars and Porsche GT products...its weight removed far from the center of gravity and roll centers, so maximum effect.

Try the following: hold a broom at the bottom - the broom itself, try swinging left and right...easy! Now hold it all the way at the other end, really at the tip...try again swinging it left and right...pretty hard! It's all about the positioning of the weight, more than the weight itself.

 

[hagen111]

Sometimes you can improve a car by adding weight; to increase the 'installation stiffness' of the suspension. Its the secret to championship winning touring cars...plus it can lower the center of gravity and its relative position to the roll centers...