Southern Belle

Started by Petrus, December 19, 2018, 19:35

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Joesson

Quote from: Petrus on January 24, 2019, 20:27
Quote from: shnazzle on January 24, 2019, 19:46
Look at the great big slot in the bumper though to compensate :)

If only the cubby would not sit behind it  ;)

The cubby out and a slot in the bonnet would be a cooler option. Literally.

Anyone have a lightweight bonnet with a slot for cheap?

@Topdownman cut two holes in his bonnet and fitted louvre panels from another marque. (His engine does need plenty of cooling as he has 1.5 times the regular number of cylinders)

shnazzle

That rx8 sounds pretty lovely :)
I actually prefer it with cat haha
...neutiquam erro.

Petrus

#102
Quote from: shnazzle on January 25, 2019, 19:50
That rx8 sounds pretty lovely :)
I actually prefer it with cat haha

So do I and a lót too!

Btw. removing the front surround, spare bucket & lid, sun visors and two airbags results in surprising lightness added. Deducting the weight of the strut brace it stíll is >10 kg.


Petrus

Found another 1100 gramms of lightness.

All in all over 38 kilos now.
4 + 3 + 0.5 plus the exhaust to go.


Petrus

Oh mán what fun.
Thoroughly relaxed, the most wonderful sunny weather and a tight car on uphill drive into the mountains with no traffic worth that name. The vauum valve thing gave no unexpected bugs and the tighter front inspires confidence.
Só looking forward to the door spacers!!



shnazzle

He's got the bug ladies and gentlemen...
...neutiquam erro.

Petrus

Quote from: shnazzle on January 27, 2019, 11:33
He's got the bug ladies and gentlemen...

Never not had it  :D
regardless of the car.
Why do think I got fined for drifting in a 2K kilos coach-on-chassis 4x4?! ;D

The gfs´s responses to de-airbagging are wonderfully different btw.
Life is wonderful; all those different facets!!

Petrus

#107


...and anóther kilo bites the dust  :)

Another valued little thing; bring on the biggies  :-)

Petrus

And Steward agaín made short work of sending the covers for the sunvisor hole.
This time in a Jiffy-bag.
5 mins. later they moved from the bag into the frame!

Ordered a panel with Volt meter and USB ports to fit in the ugly hole where th ashtray assy sat.
Too ugly to wait for that though so spraying the mounting stuts matt black.

Cannot get the Oz rims here  :'(

I will have a look whether I can source something light in Spain.
I would prefer stock size; that is the lightest combo.
Also a bit more air is easier on whichever rim is fitted.
The advantage of larger diameter is a lower = stiffer sidewall = more direct steering. Hardly something the MR2 lacks and the price is comfort and weight.


Petrus

By Jove... I should nót have looked at JDM leightweigh wheels  :P
You can shed 4 kilos per rim! But the cost is keeping up with that in nót saving  (:< >:)

Still... just imagine the exact same set up but with 4 kilo less in the wheel; UUUFFFF!!!


shnazzle

Had a look at König or Enkei? :)

Enkei RPF1... I love them so much. Just not enough to slap down 900gbp vs the Team Dynamics 1.2 I ended up going for.
...neutiquam erro.

Petrus

Quote from: shnazzle on January 28, 2019, 22:49
Had a look at König or Enkei? :)


Yes, but am a worse sinner still  :-[
Under 10 lbs....

Even heard of Racing Hart CP-035? In 6.5 x 15 we are talking 8.6 lbs.  :o

Those are no way rugged enough for the potholes of the public road but mán what cool!!

Found a streetable set under 10 lbs. unfortunately making the account lighter still so, nope  :'(

It is just that I am a genuine weight weenie and wheels are with a distance thé singlemost counting part you can save weight on.
Your valued Enkei claim that 1 kilo on a wheel equals 20 on the car and they do have a scientifically founded point.
Imagine 8,0 lbs off a wheel x 4 x 20.... hmmm, maybe it ís worth that sucking sound on the bank account.
Looking at it thát way it is only a few €s per kilo  ;)
Nah, it is just a road car  ;D

Oh btw. dó bear in mind that:
- a wider rim has a linear increment in weight
- larger diameter increments with the square

Example:
Volk TE-37   15x6.5   8.8  lbs.
Volk TE-37 15X7   9.15
Volk TE-37   16X7           11.2
Volk TE-37   17X7.5   15
The 17x7.5 weighs almost twíce the 15x6.5!!!



shnazzle

Yup.
My front 1.2s are actually the same weight as my stock fronts were. The rears are a kilo lighter each
...neutiquam erro.

Petrus

#113
Quote from: shnazzle on January 29, 2019, 00:47
Yup.
My front 1.2s are actually the same weight as my stock fronts were. The rears are a kilo lighter each

Surprisingly dissappointing no?!
Surprising too the huge differences between models/manufacturers.
I am rather a huge fan of magnesium; over a third lighter than aluminium, but quality mags are rare as hens teeth and as expensive as fairy dust.
Tecnomagnesio made very good ones but under current ownership (since 2002 or so) remake the classics mainly in aluminium without any distinguishing markings. You nééd to check with vinigar.
For the Lotus Elise/Exige/340R there are very cool, light and strong rims to be found, even mags. Off sets are tricky.

Looking at Rota slipstream new or a set of trick used ones but they must be líght or I am not spending the dough.

Petrus

About weights of the various wheels here a just baout exhaustive list:

https://japan-wheels.ru/static/japan-wheel-weight.xls

Quite informative!

As we know the pre FL wheels are quite light with 6.6 and 6.8 kilos, making 26.8 kilos.

Unfortunately no 6.0 or 6.5 from the major manufacturers anymore, so there is about half a kilo potential lost already.
Enkei RPF1 in 15 x 7 are 4.4 kilos at 1100€ a set = 17.6 kg. = 9.2 kg. lighter at 119.5€ per kilo.
Rota Slipstream 15 x 7 are 5.8 kilos at 590€ = 21 kg. = 5.8 kg. won at 101.7 €/kg.
Tecnomagnesio mags. in 15 x 6.5 are 4.9 at ?????? íf you can find a nice set.





Petrus

Found an interesting comparative test concerning wheel weight.
Ar & Driver did a series of acceleration runs with aMustang GT350R; one set with standard alloy wheel, the other with lightweight wheels.
Same car, same everything; wheels:

Front & Rear 61/61 lbs. vs 46/47 totalling a reduction of 31 lbs.

The car weighs 3950 lbs.

The accelleration was on average 8.3% faster.

To achieve that by weight reduction on the car this 8.3% equals 328 lbs.  :o

So 31 lbs off the wheels compares to 328 off the car = 1 : 10.58

Not the 20% Enkei mentions but still a lót and only acceleration.

Now let´s stick with 10  : 1 as that is a quick and dirty.

One kilo off per wheel = 1 x 4 x 10 = 40 kilo off the car  :P

Oh my, I want the Enkeis; 92 kilos off the car at 11.95 €/kg.

Let me have some more fun with the numbers:

The first 58 kilos can come at 10.17 €/kg and the next 34 kilos cost 15 €/kg.

;)

Oh and thé lightest option are Racing Hart CP-035R at 3.6 and 3.9 kg. = saving 11.8 kg. = 118 kilo on the car.
Unfortunately made from unobtanium.

shnazzle

Oooh so I shaved over 20kg off the back? :) nice
...neutiquam erro.

jonbill

It would be nice to see some maths to support that surprising assertion.
This guy comes to a different conclusion:

http://www.nsxprime.com/forum/showthread.php/98186-Heavy-versus-Light-wheels-Acceleration-Tests-and-their-results


Petrus

Quote from: jonbill on January 29, 2019, 22:19
It would be nice to see some maths to support that surprising assertion.
I just gave you emperical proof.

As to the math, that has more aspects than inertia. Which he has incomplete btw as the kinetic energy which is the basis of inertia is half the mass times the square of the speed with the speed of the tire surface being twice the vehicle speed. So the 1.5 - 1.8 of the wheel mass is about right. now the square of that please.
Also that is the rótating inertia which by traction is transferred to the car. Btw. ever seen a rally car accelerate on gravel? That is inertia of the gravel ´pushing´the car forrward. The lighter the wheel, the easier/faster it propels that grave. Fun!!!


When I did the math some year ago I cam at a factor 8 roughly, which is confirmed by the test published in Car & Driver.

The thing Í would like to know is how Enkei comes up with a factor 20 in their published print!!

Anyway, we can agree that wheel weight has a lót more to add (or not) in several aspects than the weight of the car, because it is unsspung ánd going round at twice the speed. And I am not mentionng the gyroscopic effect yet;  mán what a difference that makes on a bicycle even!!

That 2 c.q. 20 kilo Shnazzle áre real; the 2 on the scales, the 20 in kinetic effects, i.e. on the stopwatch/g-meter. It is just not thát much so it will change the car. Hence me taking my time and only pounce if I can put the money where the weight makes a noticeable difference.
Giving it a month to find something giving more kilos at a lower kilo price and if nothing, will go for the Rota Slipstream.
By that time I hope to have the carbon muffler tried and tested.

Today used the spraycan matt black on sme details and the door sill lip under the car. Is a lót less visible now.
Was huge fun as I had the four Frenchies ´helping´....

Now, I knów I am not going to score the Racing Harts but will for sure dream about shedding another virtual 118 kilos off the car. Well between dreaming of the c-companies :-*

Petrus

Quote from: jonbill on January 29, 2019, 22:19
It would be nice to see some maths to support that surprising assertion.
This guy comes to a different conclusion:

http://www.nsxprime.com/forum/showthread.php/98186-Heavy-versus-Light-wheels-Acceleration-Tests-and-their-results

Btw; thanks for that link.
I even recognised that very road!!!

Petrus

´Found´ another nice set; a set of Rays.
Ofcourse in the UK again which complicates shipment.
Finger crossed the seller will ship....

Petrus

Change of weather here and pain kept me awake; hip needs new bushing. Ideal to do some research.

First looked at the weight of modern tyres.
Rather héavy. Then I understood that modern hoops are wíííde and also larger diameter rims add to it as the lightest part of the tyre is the sidewall.
Anyway:
On average a 185/55 R15 is under 9 kilos
a 205/50 about a kilo more.
There is nothing much to be gained/lost there.

Then looked into alloy wheels, how they are made; forged, spun, cast. Nothing changed but the youtubes are nevertheless highly informative.
Was fascinated by Rays Engineering Volk brand. Enkei was/is the bench mark and in the nineties Rays set themselves apart by stepping one up in quality.
Their TE37 set a new standard. The ´37´ referring to the 3.7 kilos the 15" x 6.5 weighed. Some 25 years later it stíll is the top.
For lighter cars they added a lighter still wheel; the CE28 and yes, 2.8 kilos for the 14 x 5  :o

Back to reality; go to go outside again, heavyweight sucking mud plugging to look after the animals  :(


Petrus

recieved word that parts for the DIY exhaust have arrived where I am not. Good news but next week thus.
Several other mod goodies are supposed to arrive next week too.
Oh and negotiating a set of trick wheels. Again one I hope to sort next week.
Worse than ´mañana´  :P


Petrus

Ok, the muffler fits but....








the design need some more attention.

shnazzle

Quote from: Petrus on February  2, 2019, 16:12
Ok, the muffler fits but....








the design need some more attention.
Hahaha! I like it! Function over form :)
...neutiquam erro.

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