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Unofficial weight reduction thread

[MENTION=33584]Relbart[/MENTION]
Very interested in how this works out
We potentially could save nearly 50-60lbs of unsprung weight
 
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9705011img20160303wa0008.jpg
And the handbrake caliper, like this in red:

wp7dba1bfb_06.png
Pic about some software used for the custom procces of the handbrake caliper:
9705036img20160623wa0004.jpg

Yes, around 45lbs per axle, but im scared for pass the legal test, NSX dont designed for 50-50 brake bias, not even today rear engine Porsches (i use same kit front and rear), i drop center gravity, some extra size in rear tires but not enought, i will need softer treadwear rear tires for avoid block front tires first, too scared for the little handbrake caliper from Hispec, they are for kit-cars, and the most powerfull is for max weight 2200lb cars, and i need pass the handbrake legal test too.

I even try to buy carbon motorbike brakes, more power (and aesthetic) for bigger diameter (compensating smaller pistons) and less mass for narrow (fastest heat) and lower weight caliper-rotor, but seller and mechanic said me "you are crazy" and finally try with something more... rational.
But for weight/price the 11,2" rotors from D2, K-sport... seems like very nice too, with correct brake bias, at least form diameter, stock is 11,1".

But i dont worried for performance, they brake fine in cold (patent compound), brakes come from Formula 3000 and they sell for Lotus streeet cars, in Lotus forums i read they need 2 stops in street for stock performance, they are lighter than NSX so i will be fine in street taking temperature faster, too i removed front air brake deflectors.

The biggest save was surprisingly the pads (4 corners) 1,9lbs vs stock around 21lbs (correct me if im wrong).
My unsprung weight reduction proyect target about -200lbs, but you all know all the options.
I can post a list for lighweight sport tires if anyone interested, some save 2-4 lbs each, compared to 95% remaining.

I was interested in E1 carbon wheels when they was a prototype and each cost 2000$, cheaper in € :) but same price when i add shipping cost, not for you, they are from USA i think, but now they are more expensive.
13517669_619330941555120_375908956705917-1.jpg
 
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[MENTION=33584]Relbart[/MENTION]

Great Research,
I had no idea how much lighter the carbon pads are, that's amazing so around 19lbs lighter than stock for all 4 corners.!

if each corner may save about 20lbs, how do you plan on losing 200lbs unsprung weight?

if i understand you correctly
OEM pads are 21lbs total, so aprox 5.25lbs per corner
Carbon pads 1.9lbs total, so aprox .5lbs per corner

Front OEM Caliper & Brackets are 12.4lbs (replace with 4lbs plus 1lbs new bracket = -7.4lbs per side)
Front OEM Rotors are 13 lbs (replace with 3.7lbs = -9.3lbs per side)
Front OEM pads are 5.25lbs (replace with .5lbs = -4.75lbs per side)
Total loss per front corner = 21.45 (total front -42.9 pair)

Rear OEM Caliper & Brackets are 11.2 lbs. (replace with 4lbs plus 1lbs new bracket = -6.2lbs per side)
rear OEM Rotor are 13 lbs (replace with 3.7lbs = -9.3lbs per side)
rear OEM pads are 5.25lbs (replace with .5lbs = -4.75lbs per side)
total loss per rear corner = 20.25 (total rear -40.5 pair)

-83.4lbs total reduction potential... incredible.
Even 50% to 75% of this (40lbs to 60lbs) would be an outstanding unsprung weight reduction .
 
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View attachment 142390
And the handbrake caliper, like this in red:

View attachment 142392
Pic about some software used for the custom procces of the handbrake caliper:
View attachment 142391

Yes, around 45lbs per axle, but im scared for pass the legal test, NSX dont designed for 50-50 brake bias, not even today rear engine Porsches (i use same kit front and rear), i drop center gravity, some extra size in rear tires but not enought, i will need softer treadwear rear tires for avoid block front tires first, too scared for the little handbrake caliper from Hispec, they are for kit-cars, and the most powerfull is for max weight 2200lb cars, and i need pass the handbrake legal test too.


View attachment 142393

I would not worry too much about the F/R brake ratio as you can use a proportionning valve to reduce the pressure to the rear calipers.
The NSX NA2 uses a proportionning valve to optimize the F/R ratio in order to get the correct bias under wet and dry conditions.
This will ensure probably a 60/40 ratio when braking hard in the dry and a 50/50 ratio when braking in the wet when there is less mass transfer to the front.
I believe the BBK from Brembo comes with a 50/50 brake ratio.
How wide are the CCM disks you want to use?
For the handbrake you can use the Brembo calipers like I do:
DSCF6820_zpsrkism7md.jpg
 
Thanks!, i will copy-paste because i have some confused references of weight, caliper with pads, without, new, worn out, with/without brackets... only you changed weight caliper for rotor, but finally is the same.
imagedata.php


This is grams, so:
265gr/0,5lbs
1770gr/3,9lbs
1953gr/4,3lbs

Maybe the big diference in pads (apart material and size) is because stock have steel hardware, and usually carbon kits have a titanium wall in pads (not in the picture) for protect brake fluid from high temperature, usually too titanium pistons for same reason and endure high temperature, titanium is very good insulation, very low termal conductor.

About -200lbs, this is possible, maybe not for me, this includes hardcore solutions, some of them expensive, some cheap but expensive custom, some probably unsafe... but too a long reasonable list.
Anyway keep in mind the stock NSX is probably the lightest unsprung weight car ever (even with iron calipers), another cars use exotic materials, but then bigger tires,wheel, brake combo, and lighter/cheap cars dont use aluminum nuckle, forged arms, forged wheels.
Perhaps the Lotus Elise S1 with matrix composite rotors, but i think they dont use aluminium knuckle/arms, and even if really is lower, then the ratio sprung/unsprung weight will be a lot better in NSX.
Of course nobody want add sprung weight in his car, but at least this make better ride quality for this ratio, but a lot more efect removing unsprung than adding sprung.
I want remove some sprung too, but only if it is cheap or has good efect in center gravity, polar moment inertia or unsprung.

Ops, the list, ok, give me time for collect ideas, convert weight, copy from notes... and probably remove the 50% ridiculos ideas, even shame to post ^^
 
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CB72, yes you are right, i can use proportionning valve, but i dont know why never interested, no reason really... i think i can control with softer rear tires.
Per example 300 treadwear front and 240-260 rear.
Of course will be better 4 soft tires and correct brake bias, but i dont track the car and semislicks are not usually lighter than sport tires.
¿Smaller semislicks? yes, but i have wider wheels (ce28n 7,5" and 9"), if i want thinner wheels then 16" max, and the best sport tires dont have sizes for 16".

I was thinking in change hub (we have hub in two parts, 4 bolts to knuckle and 5 to wheel, only the exterior part) and change bolt pattern to 4x3,93, then i can use the stock brake hat of carbon and use the lightest ce28n with 8 spokes in 16" (im like more 16" 8 spokes than 17" 10 spokes).

Yes, Brembo BBKs GT and Indy 50-50.
Usually stock cars have a front margin bias for security, when really all cars can brake a little more with rear tires, but probably very small margin.

91'-93' or 91'-96' NSX this margin is bigger than 97' or type-R, seems like 91' is 61-39 and the rest is ¡55-45! hard to believe any security margin here with transverse mid engine, so maybe im not far with 50-50, maybe Brembo knew this, buy yet not correct, or maybe Brembo know we use bigger rear tires when we buy BBKs, dont know...

How wide are the CCM disks you want to use?

You ask for brake bias?, i think this not affect, perhaps pedal effort...
You can buy 2 options, front and rear for Lotus 24mm(0,9") and 21mm(0,8") (same diameter) but they sell his calipers for front rotors, and rear rotors work with stock rear Lotus calipers (with carbon pads).
At first i want 4 rear rotors, and carbon caliper will work fine anyway, not only for save a little weight respect front, but too because they have lower mass and can go hot faster, but finally for a mistake i have 4 front rotors.
The biggest mistake (not mine) was they send me 3 calipers, and finally i bought 5! ;(

I think is better if you look sizes, prices... yourself in his website: http://www.frenocarbon.com/files/Price List.pdf

I think they come from Formula cars for 13" wheels, look the pictures and weight parts of this Brembo F1, exactly the same sizes and weight:
http://www.brembo.com/en/car/formula-1/f1-infographics

For the handbrake you can use the Brembo calipers like I do

Yes, i knew Brembo handbrake but ¿not very expensive? i remember a WTF when i saw prices, perhaps i confused... but Hispec is super cheap (more expensive was the custom work or bracket) and lightweight, but if i dont pass legal test maybe will need Brembo or try higher friction coefficient or something, i dont know how will brake stock pad in carbon-ceramic rotor.
My first idea was use hidraulic handbrake so no extra caliper, but not sure about legal homologation, so finally cable handbrake.

This can be a nightmare, i yet asking me why simply dont plug-in D2 small kit, very lightweight caliper, aluminium hat, stock size rotor, beautiful and very cheap, probably not Brembo quality or big fade resistance but without track seem like ok.
home-main.jpg
Im feel bad if we converting the thread in brake thread...
 
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Hi neighbor :wink:

Nice information there! It is always nice to see new ideas!

I have some questions:

- Are you working with Freno on this, or you bought their kit and doing the custom work by yourself?

- This kit looks to be developed for specific lotus cars... but those models are lighter and less powerfull than our NSX... this means the rotors, calipers and pads will be submited to a lot more heat and stress... Have you asked Freno if the kit will withstand this increase in temperature?

- Is this a race spec kit or a street spec kit that can hit the track? I'm asking this because race calipers aren’t suitable for road use as they have no wiper seals in the caliper (The primary job for a wiper seal in a caliper is to wipe out any dirt contracted from road use, without wiper seals you may find yourself changing the seals quite regularly as they will fill with dust/dirt off the road and cause problems), this wont be a problem on motorsport, but for street use overhauling brakes regularly could end on very high running costs.

And some thoughts:

- It would be nice if Freno could develope a kit for our cars around "330 mm rotor" (so that it could fit 17" front wheels).

- It would be also nice if Freno could offer the correct bias by offering different (and compatible with brake master cilinder) pistons sizes for F/R calipers (Bias on the NSX is ~60/40 for 91-96 cars, and 54/46 for 97+).

- I would not mind to pay a bit more for something completely engineered towards our NSX, especially such a lightweight Carbon setup that could be used on the street and that could offer the right bias and an e-brake solution... But i guess this is still a dream...

Please keep us updated on your setup and don't forget to share information, pictures and a review on how this kit behaves!

Thanks for sharing!

Bruno



Im adapting small carbon ceramic brakes (around stock size), a lot custom work, hats, handbrake calipers and specially with caliper brackets for his small diameter (small space for brackets), they are almost finished but dont test yet, i will post pics in the future if all work fine.
They are called "freno carbon" if you want look pics, i dont post links because is my first post in the forum and pics come from commercials, probably dont allowed.
Price and weight saves are very nice, rotors weight around 4lbs and calipers around 3,7lbs.

Another option i checked before with good price and big saves was about "Devil brakes", they are titanium with ceramic coat, but probably is better option specific brakes for NSX like Racingbrake offer.
Sorry for my bad english, write from Spain.
 
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Im adapting small carbon ceramic brakes (around stock size), a lot custom work, hats, handbrake calipers and specially with caliper brackets for his small diameter (small space for brackets), they are almost finished but dont test yet, i will post pics in the future if all work fine.
They are called "freno carbon" if you want look pics, i dont post links because is my first post in the forum and pics come from commercials, probably dont allowed.
Price and weight saves are very nice, rotors weight around 4lbs and calipers around 3,7lbs.

Another option i checked before with good price and big saves was about "Devil brakes", they are titanium with ceramic coat, but probably is better option specific brakes for NSX like Racingbrake offer.
Sorry for my bad english, write from Spain.
What is the diameter and width of the rotors?


"softer"/grippier/stickier/wider rear tires will not do much for having too much rear brake bias.

50/50 bias is not good in an NSX and proportioning valves are a bit of a crappy band-aid. You'll either be working and relying on the ABS a ton of restricting most of the pressure going to the rear with a proportioning valve.
 
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Hi neighbor :wink:
I live in the other side (Valencia), yet we are "iberians", but my family is very close of Portugal (Extremadura).

Are you working with Freno on this, or you bought their kit and doing the custom work by yourself?

Last option, notice my custom hat in first picture, and the stock black hat from Freno Carbon (the picture with the weights is not mine), i think the company is from UK, thats curious "freno" is brake in spanish.
I was rejected when i said my intentions with other brands, so this time i shuted up ^^
No with Rotobox, they make carbon motorbike wheels (stronger and "heavy" than usual, perfect for cars) and they was very interested in make carbon wheels for NSX, but i cant travel... finally nothing.
Probably with a big comunity like nsxprime or nsxeurope many brands could build something interesting, but i was idiot trying alone.

Too, a spanish company (Carbures) will start to build carbon wheels in very high volume (30.000/year) in 2017, they patented a fast build procces so i hope they are cheaper than the E1 carbon wheels.

This kit looks to be developed for specific lotus cars... but those models are lighter and less powerfull than our NSX... this means the rotors, calipers and pads will be submited to a lot more heat and stress... Have you asked Freno if the kit will withstand this increase in temperature?

Im 80% sure they come from Formula cars, but they add a "H-carb" compound for cold stops, so i dont think they are specific for Lotus.
They are not less powerfull, the diameter is the stock NSX, well, i dont know pistons area, but the friction coefficient is "race level".
Confirmed, they come from Fórmula 2 (and some team in MotoGP and Radical nurburgring record):http://www.frenocarbon.com/news/120404%20F2%20news%20release.pdf

Edit: I misunderstanding you about powerfull car, i read good coments from a 400hp elise owner: http://www.frenocarbon.com/products/race-track-and-trackday-cars/Testimonials.pdf
Anyway this brakes yet a bad 50-50 brake-bias for Lotus too (remember they offer same kit for front engine Caterhams!), and powerfull car dont necesarially need powerfull brakes, i know this is the rule, but i enjoy driving in legal speeds, and was looking exactly a product like this, probably not for all.

In this pdf more technical info, with friction coefficient graphics:http://performanceshock.com/Freno_H-Carb.pdf
Anyway, like i said in other post, Lotus owners said this brakes only need 2 street stops for reach the stock performance, and nobody run fast with cold engine, too Lotus cars weight less than nsx, im not worried about performance, too i was thinking in titanium hat for block temperature (very expensive) or some paint treatment for the aluminium hats.

Im pretty sure the limit will be the tires like always, even small drum brakes can block semislicks (aluminium drums are very light, even more than this kit and dissipate heat very fast ^^ i love the Honda CRX-HF and Insight aluminium drums), is a joke, but even they can work fine in street with proper master cilinder, and the are more powerfull vs same diameter rotor.
Too we need remember: very powerfull brakes not good either, the modulation in brake pedal is very important.

Anyway i only use the car in street, i dont need race performance, but i can enjoy low unsprung 99% of the time i drive, and if this not work... simply sell to Lotus owners.

- I would not mind to pay a bit more for something completely engineered towards our NSX, especially such a lightweight Carbon setup that could be used on the street and that could offer the right bias and an e-brake solution... But i guess this is still a dream...

Well, if this work for me, will work for everyone, they are top quality, live forever (even less wear than carbon-carbon) and weight 3-4 times less weight than steel or other big ceramic supercar rotors.
My workshop have the sizes of hats and brackets, even the handbrake caliper, this calipers cost 80$ and weight 1,1lbs:http://www.hispeccalipers.co.uk/spotv1.html
But better if talk with Freno carbon and build specific for NSX, when i read about this brakes in Lotus forum i dont remember look a lot buyers, and the other avaible cars lighters like Atom, Caterham... this cars dont need carbon brakes, they cant suffer fading even with paper rotors, maybe better business with NSX.

Another option is talk with "Red Devil brakes" for build NSX kits, titanium with ceramic coat, they make some brakes for corvettes and others, same range weight and cost if unsized for NSX, but i dont have the same confidence.

And the most important factor: the logo of freno carbon in calipers is white letters and last in red like NSX-R logo :cool:, they can looks amazing with 2002 NSX-R white wheels.
Honda with the NSX in unsprung weight adopted the lotus sentence "less is more" so Mr. Sochihiro Honda would aproved this mod.

Please keep us updated on your setup and don't forget to share information, pictures and a review on how this kit behaves!

You will know, even if this is a disaster, but not very soon im afraid, and you are welcome if want taste them yourself.
 
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What is the diameter and width of the rotors?

They say 280mm, but Formula cars use 278mm so im not sure, stock 91' NSX is 282mm (for reference).
Width is optional 24mm or 21mm, stock NSX is 28mm front and 21mm rear if not remember bad.
 
Im adapting small carbon ceramic brakes (around stock size), a lot custom work, hats, handbrake calipers and specially with caliper brackets for his small diameter (small space for brackets), they are almost finished but dont test yet, i will post pics in the future if all work fine.
They are called "freno carbon" if you want look pics, i dont post links because is my first post in the forum and pics come from commercials, probably dont allowed.
Price and weight saves are very nice, rotors weight around 4lbs and calipers around 3,7lbs.

Another option i checked before with good price and big saves was about "Devil brakes", they are titanium with ceramic coat, but probably is better option specific brakes for NSX like Racingbrake offer.
Sorry for my bad english, write from Spain.

We've started working with Freno recently as well. Hopefully we can bring this to Prime in the near future. FWIW, testing/tracking comments from the local Lotus club(2000lb+, 400hp) was encouraging for us as the carbon disc shed heat way quicker than the cast iron so it just might be ideal for us being heavier. We were putting around this car to ck the cold temp behavior and its fine with no noise at all.

The only way to find out is to make a set and try it. At least so far the math works out fine on paper. FYI, the Lotus upright/knuckles , are cast iron and the wishbones are fab'ed steel, same with the 4C.

Bruno, I "think" we are stuck with the caliper/piston sizes as they were made for the F2 cars in 2012. we(Prime) doesn't have the economy of scale to ask for a new caliper. We'lll ask and confirm.
 
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I dont know the pistons diameter of freno in this moment, or where the calipers come from, ¿you say they are the same calipers than F2 cars?
I have some reference, 2mm of pistons area are equal to 10mm in diameter rotor.
Anyway, ¿you saw the graphic of temperature/friction coefficient? seems like increase very fast, i dont think the pistons area will be a problem with high coefficient, maybe if you have a race NSX with slicks... but for my sport street tires, not very worried, but this is speculation, i'm not an engineer.

Remeber too, the diameter of the tire is important, we have here a reduction ratio, when more distance between diameter rotor and diameter tire, less power brake.
For the moment i cant tell you nothing, but soon i will start my own test + legal homologation test + technical inspection vehicle (every year for old cars in my country).

The only problem was the bracket caliper, with the small diameter rotor the space was a little small, at first my mechanic said me this was impossible, then i said about try with thinner but stronger in titanium, finally dont was necessary and he found enought space for aluminium, but dont remember if was necessary a little nodification in knuckle.
In any case, i can ask him to talk with you for email if you need it.
 
I dont know the pistons diameter of freno in this moment, or where the calipers come from, ¿you say they are the same calipers than F2 cars? nice to know
I have some reference, 2mm of pistons area are equal to 10mm in diameter rotor.
Anyway, ¿you saw the graphic of temperature/friction coefficient? seems like increase very fast, i dont think the pistons area will be a problem with high coefficient, maybe if you have a race NSX with slicks... but for my sport street tires, not very worried, but this is speculation, i'm not an engineer.

Remeber too, the diameter of the tire is important, we have here a reduction ratio, when more distance between diameter rotor and diameter tire, less power brake.
For the moment i cant tell you nothing, but soon i will start my own test + legal homologation test + technical inspection vehicle (every year for old cars in my country).

The only problem was the bracket caliper, with the small diameter rotor the space was a little small, at first my mechanic said me this was impossible, then i said about try with thinner but stronger in titanium, finally dont was necessary and he found enought space for aluminium, but dont remember if was necessary a little nodification in knuckle.
In any case, i can ask him to talk with you for email if you need it.
 
I dont know the pistons diameter of freno in this moment, or where the calipers come from, ¿you say they are the same calipers than F2 cars? nice to know
I have some reference, 2mm of pistons area are equal to 10mm in diameter rotor.
Anyway, ¿you saw the graphic of temperature/friction coefficient? seems like increase very fast, i dont think the pistons area will be a problem with high coefficient, maybe if you have a race NSX with slicks... but for my sport street tires, not very worried, but this is speculation, i'm not an engineer.

Remeber too, the diameter of the tire is important, we have here a reduction ratio, when more distance between diameter rotor and diameter tire, less power brake.
For the moment i cant tell you nothing, but soon i will start my own test + legal homologation test + technical inspection vehicle (every year for old cars in my country).

The only problem was the bracket caliper, with the small diameter rotor the space was a little small, at first my mechanic said me this was impossible, then i said about try with thinner but stronger in titanium, finally dont was necessary and he found enought space for aluminium, but dont remember if was necessary a little nodification in knuckle.
In any case, i can ask him to talk with you for email if you need it.
 
I dont know the pistons diameter of freno in this moment, or where the calipers come from.
I have some reference, 2mm of pistons area are equal to 10mm in diameter rotor.
Anyway, ¿you saw the graphic of temperature/friction coefficient? seems like increase very fast, i dont think the pistons area will be a problem with high coefficient, maybe if you have a race NSX with slicks... but for my sport street tires, not very worried, but this is speculation, i'm not an engineer.

Remeber too, the diameter of the tire is important, we have here a reduction ratio, when more distance between diameter rotor and diameter tire, less power brake.
For the moment i cant tell you nothing, but soon i will start my own test + legal homologation test + technical inspection vehicle (every year for old cars in my country).

The only problem was the bracket caliper, with the small diameter rotor the space was a little small, at first my mechanic said me this was impossible, then i said about try with thinner but stronger in titanium, finally dont was necessary and he found enought space for aluminium, but dont remember if was necessary a little nodification in knuckle.
In any case, i can ask him to talk with you for email if you need it.

You can ask to Sicom brakes too, they have rotors for Elise and Fiat 500 (pic down), the diameter is slightly higher but very narrow the width, they are solid 285mm x 11,5mm.
They use the stock calipers with Sicom pads, maybe too add titanium pistons, for supercars they have big kits with Sicom calipers.
I talked to them many years ago, they dont want sell me because i dont have titanium pistons or pads for NSX calipers, then i ask for motorbike kit big diameter with his caliper.They refused.
9708209285-mm-185-kg-por-di.jpg
 
I dont know the pistons diameter of freno in this moment, or where the calipers come from.
I have some reference, 2mm of pistons area are equal to 10mm in diameter rotor.
Anyway, ¿you saw the graphic of temperature/friction coefficient? seems like increase very fast, i dont think the pistons area will be a problem with high coefficient, maybe if you have a race NSX with slicks... but for my sport street tires, not very worried, but this is speculation, i'm not an engineer.

Remeber too, the diameter of the tire is important, we have here a reduction ratio, when more distance between diameter rotor and diameter tire, less power brake.
For the moment i cant tell you nothing, but soon i will start my own test + legal homologation test + technical inspection vehicle (every year for old cars in my country).

The only problem was the bracket caliper, with the small diameter rotor the space was a little small, at first my mechanic said me this was impossible, then i said about try with thinner but stronger in titanium, finally dont was necessary and he found enought space for aluminium, but dont remember if was necessary a little nodification in knuckle.
In any case, i can ask him to talk with you for email if you need it.

You can ask to Sicom brakes too, they have rotors for Elise and Fiat 500 (pic down), the diameter is slightly higher but very narrow the width, they are solid 285mm x 11,5mm.
They use the stock calipers with Sicom pads, maybe too add titanium pistons, for supercars they have big kits with Sicom calipers.
I talked to them many years ago, the dont want sell me because i dont have titanium pistons or pads for NSX calipers, then i ask for motorbike kit big diameter with his caliper.They refused.
http://www.subirimagenes.com/imaged...nes.com/otros/9708209285-mm-185-kg-por-di.jpg
 
I would be very wary about fitting smaller disks to the NSX.
It's not only a question of temperature but also of thermal shock and of course total energy dissipated.
Here's what happened to one of my rear disks after slowing down from 220 km/h to negociate a hairpin...
I was lucky the disk did not shatter!
DSCF6916_zpsw5qolr8r.jpg
 
We've started working with Freno recently as well. Hopefully we can bring this to Prime in the near future. FWIW, testing/tracking comments from the local Lotus club(2000lb+, 400hp) was encouraging for us as the carbon disc shed heat way quicker than the cast iron so it just might be ideal for us being heavier. We were putting around this car to ck the cold temp behavior and its fine with no noise at all.

The only way to find out is to make a set and try it. At least so far the math works out fine on paper. FYI, the Lotus upright/knuckles , are cast iron and the wishbones are fab'ed steel, same with the 4C.

Bruno, I "think" we are stuck with the caliper/piston sizes as they were made for the F2 cars in 2012. we(Prime) doesn't have the economy of scale to ask for a new caliper. We'lll ask and confirm.

I dont know the pistons diameter of freno in this moment, or where the calipers come from.
I have some reference, 2mm of pistons area are equal to 10mm in diameter rotor.
Anyway, ¿you saw the graphic of temperature/friction coefficient? seems like increase very fast, i dont think the pistons area will be a problem with high coefficient, maybe if you have a race NSX with slicks... but for my sport street tires, not very worried, but this is speculation, i'm not an engineer.

Remeber too, the diameter of the tire is important, we have here a reduction ratio, when more distance between diameter rotor and diameter tire, less power brake.
For the moment i cant tell you nothing, but soon i will start my own test + legal homologation test + technical inspection vehicle (every year for old cars in my country).

The only problem was the bracket caliper, with the small diameter rotor the space was a little small, at first my mechanic said me this was impossible, then i said about try with thinner but stronger in titanium, finally dont was necessary and he found enought space for aluminium, but dont remember if was necessary a little nodification in knuckle.
In any case, i can ask him to talk with you for email if you need it.

You can ask to Sicom brakes too, they have rotors for Elise and Fiat 500 (pic down), the diameter is slightly higher but very narrow the width, they are solid 285mm x 11,5mm.
They use the stock calipers with Sicom pads, maybe too add titanium pistons, for supercars they have big kits with Sicom calipers.
I talked to them many years ago, the dont want sell me because i dont have titanium pistons or pads for NSX calipers, then i ask for motorbike kit big diameter with his caliper.They refused.
http://www.subirimagenes.com/imaged...nes.com/otros/9708209285-mm-185-kg-por-di.jpg
 
Bruno, I "think" we are stuck with the caliper/piston sizes as they were made for the F2 cars in 2012. we(Prime) doesn't have the economy of scale to ask for a new caliper. We'lll ask and confirm.

Please ask and confirm! maybe if they offered replacement rotors and pads for a popular setup like stoptech we (Prime) could get the best of both worlds... weight savings and nice bias...

....
It's not only a question of temperature but also of thermal shock and of course total energy dissipated.
...

^^ This is my exact concern! Carbon rotor may withstand the very hight temperatures that will be generated and thermal shock... but what about calipers? and and rotor hats? and bolts? and pistons? and seals? and brake fluid?... and...? and...?

Only testing will tell... but i would feel a lot more confident if rotors were bigger and thicker than OEM... like 330 x 32 or 34... and i bet that even with bigger and thicker rotors, weight savings would be great!
 
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Please ask and confirm! maybe if they offered replacement rotors and pads for a popular setup like stoptech we (Prime) could get the best of both worlds... weight savings and nice bias...



^^ This is my exact concern! Carbon rotor may withstand the very hight temperatures that will be generated and thermal shock... but what about calipers? and and rotor hats? and bolts? and pistons? and seals? and brake fluid?... and...? and...?

Only testing will tell... but i would feel a lot more confident if rotors were bigger and thicker than OEM... like 330 x 32 or 34... and i bet that even with bigger and thicker rotors, weight savings would be great!

PM'ed CB72.

We did. Making cast iron disc is very cheap especially doing it in China. Making carbon disc you need the qty. to justify.

We are moving forward with support from Freno(unlike the VR steering project). Bigger and thicker(is also heavier, not to mention much more expensive) is great as long as you can use it all which we can't.

the oem NSX tops at 168mph(?) at 3000lbs+ that was their design parameter. Our car is less than 3000lbs and rarely top off at 130-140mph if ever on track. Heck going 110 at Turn 9 at Big Willow is scary enough. Maybe we'l find some DF in the future.

the math is on our side thus the oem brakes works great repeatedly but we would like to try carbon before we kick the bucket and buying heavy cast BBK only works again you when you are not braking.
The good thing is, IF Freno flakes out half way for what ever reason, we'll just go back to oem brake and watch the disc rust as there has been a lot of rain in California lately.

If your car has mega hp and consistently able to hit 150 and beyond, then this set up maybe too small for you. Over buying carbon disc in this case is money not wisely spent but that is just an opinion.

Relbart is almost finished but we are just starting.
 
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^^ This is my exact concern! Carbon rotor may withstand the very hight temperatures that will be generated and thermal shock... but what about calipers? and and rotor hats? and bolts? and pistons? and seals? and brake fluid?... and...? and...?

If we use his calipers less problems, pistons probably titanium, they protect brake fluid too.
Like i said to Lifnot i contacted years ago with sicom Brakes (too small rotors, they are matrix ceramic composite), and they refused because i dont have titanium pistons, and they sell for Fitat 500 and Elise with special pads and pistons for stock calipers.
They have this, solid 285mm x 11,5, around the same weight (seems like carbon-carbon is lighter than carbon-ceramic or any other compund), a little more diameter but a lot more narrow.
9708209285-mm-185-kg-por-di.jpg


[/QUOTE]Only testing will tell... but i would feel a lot more confident if rotors were bigger and thicker than OEM... like 330 x 32 or 34... and i bet that even with bigger and thicker rotors, weight savings would be great! [/QUOTE]

Maybe not big savings, this rotors have writed his minimum weight for messure wear when they are 100% worn out, and not always very light, this is heavier than stock, 7259g is 15,96 lbs, so more than 16lbs new:
attachment.php


I was reading about ceramic for Porsche: 14,9lbs front and 14,3lbs rear, but they are very big, very expensive, and suspension/steering carry them the 100% of the time, and we need will use his 100% potential... maybe never, for racing NSX ok, but occasional track withouy trying to make track records, the size like stock can be enought, yet we will dont have fade and not will break.
 
Has anyone done any weight reduction that they wished they had not done for the car? I'm about to go carbon front and rear beams, abs delete within 10 days. I removed my doa stereo the other day since I had to remove CCU and send to briank for repair. Wiper arms and motors went about a week ago and now I have to manually wipe down the windshield in the morning so maybe that wasnt a good idea to remove. (better go buy a squeegee today). Momo tuner and nrg hub were installed this week. I'm thinking about removing the TCS (light always on since I have an aem ems) & SRS modules. based on the spreadsheet and I have a ctsc I should be @ 2829 lbs right now and with my planned mods should be at 2710lbs. This includes firewall sound deadening removal and I was thinking about just ripping out the thick backing on the carpets vs buying new. I havent been on prime for 11 years (busy) but have been on previously since 2000 and have owned my car 17+ years. The car has basically sat for 11 years other than the occasional start and I started driving it about 2 months ago to decide if I may want to sell it or something else to make room for something different. I'm not selling it, resale value isnt important to me either since I will be dead when the next owner has it but nice to see values are up on these anyway. I took it into autowave a few weeks ago and they were surprised since no service since 2006 and maybe a few hundred miles driven since they did my ctsc install (389 rwhp back then). They installed the taitec replica exhaust for me to replace the rm dtm I have had on. Love the car again and I mainly decided to drive it again since the mclaren view was similar when I was deciding to buy (but not superior) but reliability issues made me rethink buying but love the doors. I drive it more the last 2 months than my '11 basalt blk boxster spyder with 6sp and buckets, or my arancio borealis egear gallardo spyder. Also much better for fun driving than my '12 pdk 997.2 turbo cab was
 
Has anyone done any weight reduction that they wished they had not done for the car? I'm about to go carbon front and rear beams, abs delete within 10 days. I removed my doa stereo the other day since I had to remove CCU and send to briank for repair. Wiper arms and motors went about a week ago and now I have to manually wipe down the windshield in the morning so maybe that wasnt a good idea to remove. (better go buy a squeegee today). Momo tuner and nrg hub were installed this week. I'm thinking about removing the TCS (light always on since I have an aem ems) & SRS modules. based on the spreadsheet and I have a ctsc I should be @ 2829 lbs right now and with my planned mods should be at 2710lbs. This includes firewall sound deadening removal and I was thinking about just ripping out the thick backing on the carpets vs buying new. I havent been on prime for 11 years (busy) but have been on previously since 2000 and have owned my car 17+ years. The car has basically sat for 11 years other than the occasional start and I started driving it about 2 months ago to decide if I may want to sell it or something else to make room for something different. I'm not selling it, resale value isnt important to me either since I will be dead when the next owner has it but nice to see values are up on these anyway. I took it into autowave a few weeks ago and they were surprised since no service since 2006 and maybe a few hundred miles driven since they did my ctsc install (389 rwhp back then). They installed the taitec replica exhaust for me to replace the rm dtm I have had on. Love the car again and I mainly decided to drive it again since the mclaren view was similar when I was deciding to buy (but not superior) but reliability issues made me rethink buying but love the doors. I drive it more the last 2 months than my '11 basalt blk boxster spyder with 6sp and buckets, or my arancio borealis egear gallardo spyder. Also much better for fun driving than my '12 pdk 997.2 turbo cab was
I agree with the following...
Remove - TCS, stereo, Steering wheel, front/rear bumper beams, factory exhaust

Don't agree removing - sound deadening, wipers, SRS module (unless replace with new 2000+ unit which is much lighter and better)

Suggest - Recaro (or similar) bucket seats, 02+ headlight conversion, remove spare tire assembly, headers (if you have stock 91-96)
 
I agree with the following...
Remove - TCS, stereo, Steering wheel, front/rear bumper beams, factory exhaust

Don't agree removing - sound deadening, wipers, SRS module (unless replace with new 2000+ unit which is much lighter and better)

Suggest - Recaro (or similar) bucket seats, 02+ headlight conversion, remove spare tire assembly, headers (if you have stock 91-96)

Is there a reason you suggest not removing sound deadening or srs module? I have a '91 and I swapped to a momo tuner steering wheel the other day so I'm trying to understand the need for keeping the srs module in rather than removing. Also I was referring to the sound deadening carpet padding and firewall (although I havent opened the car up) if that makes a difference. Autowave said the other sprayed on stuff wasnt worth the effort since I dont track. I didnt think it was going to be so fun to do weight reduction and I'm mainly enjoying it because I personally reduced my own weight by over 70lbs and that required a lot of hard work whereas I just write a check for the nsx weight reduction stuff. Thanks for the response RYU! Autowave also said the lexan hatch probably wouldnt be a good idea if I was planning to leave the car parked outside due to possible sagging issues? I was even brave enough to buy another shorai battery due to the weight savings cost/ratio even though the 1st one shorted out and I had to call the fire dept as I wasnt sure if the car wasnt going to catch on fire (lots of smoke coming out of battery). I installed ~ 2 years ago but had driven less than 2 miles on it. This time I plan on using the car or if I store it I will remove the shorai and install the reg lead acid one in place for storing/charging
 
I think he meant abs modulator NOT srs module
The abs got much lighter and better with the newer modulator
 
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