97+ brake conversion

[docofmind]

Note the ugle tire

 

[Larry Bastanza]

Folks,

There seems to be a slight bit of mis-information here.

The smaller piston has changed size on the front calipers. They Started at 36mm and were decreased to 34mm. The 2002/2003 calipers are different color and maybe slightly different in some respects, but the piston sizes again remain 40mm/34mm.

Lud, Maybe you can change this spec in the FAQ. It can be found here under 1997 model changes: http://www.nsxprime.com/FAQ/General/changesbyyear.htm

NOTE: EDITIED WITH CORRECTION

HTH,
LarryB

 

[docofmind]

Folks,

There seems to be a slight bit of mis-information here.

The smaller piston has NEVER changed size on the front calipers. They have always been 34mm (actually 33.4mm to be specific) and remain that way. So the front calipers, sans brackets are identical, always have been. At least up to 2001, I have not researched 2002-2003's yet.

I am working on confirming the rear piston sizes also, since the 1997+ calipers require a $40 rebuild kit to replace the boot and the early ones can get the boot individually. If the piston size is actually the same you will be able to order the early boot for the 1997+ rear calipers. STILL UNDER INVESTIGATION.

Lud, Maybe you can remove this spec from the FAQ. It can be found here under 1997 model changes: http://www.nsxprime.com/FAQ/General/changesbyyear.htm


HTH,
LarryB

Larry, the rear piston size from 97+ is 48mm. From 91-96 it was 43mm for the rear caliper.

On the front, 91-96 the smaller piston is 36mm and the larger is 40mm.

 

[The REAL nsxtasy]

There seems to be a slight bit of mis-information here.

The smaller piston has NEVER changed size on the front calipers. They have always been 34mm (actually 33.4mm to be specific) and remain that way.
.
.
.
Lud, Maybe you can remove this spec from the FAQ. It can be found here under 1997 model changes: http://www.nsxprime.com/FAQ/General/changesbyyear.htm

That link is where I got the information in my post above. If it's not correct, I can change it.

There is also a reference to a '97 change in piston sizes here, but it is not specific about where or how much; it's possible that is just referring to the size of the piston in the rear caliper, as noted by docofmind.

 

[Larry Bastanza]

Opps!!

I stand corrected. The earlier ones are larger as you pointout. I have 1997+ on the bench right now and thought the earlier ones were the same.

Then the FAQ actually has the dimensions backwards. It states they went FROM 34mm TO 36MM, and it is actually the other way around.

Also seems like we will be stuck buying the complete rear kit when the rear boots cook at the track for the 1997+.

Ken,

We have all been corrected by docofmind!!

Thanks,
LarryB

 

[The REAL nsxtasy]

Re: Opps!!

Then the FAQ actually has the dimensions backwards. It states they went FROM 34mm TO 36MM, and it is actually the other way around.

The size of the smaller front piston got SMALLER???

 

[Craig]

Re: Opps!!

We have all been corrected by docofmind!!
LarryB [/B]

That may happen more often than not. Sherwin knows brakes! This front set up is awesome....and Sherwin is a great guy, easy going and willing to help.

I'm using a semi agressive track compound pad right now and although it's a little grabby when cold, WATCH OUT when you get some heat in them. The stopping power is amazing with no fade whatsoever...even when smoking hot.

I also have about 50 miles on a mid range set of street pads and they have a great, firm and progressive pedal feeling and are perfect for very agressive street driving maybe even light track.

The nice part is that the pads change out in about 10 minutes, including taking the wheels off and putting them back on.

We should have the rears on the car in about 10 days. Stay tuned, this will be good!

 

[DanO]

Re: Re: Opps!!

The size of the smaller front piston got SMALLER???

After 6 years, maybe we're starting to get to the bottom of this!

1991 - 1996 front: 40mm 36mm
1991 - 1996 rear: 43mm

1997+ front: 40mm 34mm
1997+ rear: 48mm

Seems strange that the piston area was reduced in the fronts. I wonder if the 1997 setup allows for a little more rear bias?

Ken, if this piston size reduction is true, it sure answers a lot of long-standing questions and clears up some confusion.

Note: this is the first time I've seen actual rear piston size mentioned in a post; thanks for the info docofmind.

DanO

 

[Larry Bastanza]

Sherwin,

I have one more pertinent question, if I may. Master cylinder bores?? same, different?? This is the last part to this puzzle!!!!!!!!!

It appears the part number was superseeded in 1997, but the new number is applicable to all years, so it is not conclusive from this is the bores are the same, even though it is likely they have not changed if the back fit them.

Thanks,
LarryB

 

[docofmind]

Thank for the kind words Craig, and the rest of you. It really is my pleasure. There is nothing more rewarding than working with a group of people who appreciate your efforts. Thats what makes it all worthwhile for me.

Larry, the master is the same for all years. They started with 2 different numbers than weeded out the older one and are now only using the newer one for both sets of years. They are indeed identical.

Keep one thing in mind though, there are many factors that play into brake bias. Not only piston diameters. The 97+ uses larger rotors which are able to apply more torque. Too much math if you ask me

 

[Larry Bastanza]

Sherwin,

Thanks,

Yes, as you point out, the math will grow, I was wondering if ANYTHING was a constant!!

Time to revisit Carroll Smith, for the brake bias/fuild dymanics math. It will be interesting to see what the changes yield, even on paper. (I can only guess this math exercise is somewhere in your past)

Appreciate your input.

LarryB

 

[JJCNSX]

Re: Re: Re: Opps!!

1991 - 1996 front: 40mm 36mm
1991 - 1996 rear: 43mm

1997+ front: 40mm 34mm
1997+ rear: 48mm

Seems strange that the piston area was reduced in the fronts. I wonder if the 1997 setup allows for a little more rear bias?

DanO

If i understand correctly, EVEN for a MR car like NSX, when dry, front brake/tire will provide upto 80% of the stopping power.

I am not sure what 2mm (front) will do though. Also, i understand that 97 increased the rear rotor a bit, but have you guys ever heard of rear brakes overheated?

any idea?

-jjc.

 

[nsxhk]

According to the Vtec Sports magazine Vol.005:

NA1 NSX-R
front pistons: 36.1mm + 40.4mm
front rotor size: 282mm 28mm
rear pistons: 42.9mm
rear rotor size: 282mm 21mm

NA2 NSX type-S
front pistons: 34mm + 40mm
front rotor size: 298mm 28mm
rear pistons: 48.1mm
rear rotor size: 303mm 23mm

NA2 NSX type-S Zero
front pistons: 34mm + 40mm
front rotor size: 298mm 28mm
rear pistons: 48.1mm
rear rotor size: 303mm 23mm

2003 NA2 NSX-R
front pistons: 36.1mm + 40.4mm <----
front rotor size: 282mm 28mm <----
rear pistons: 48.1mm
rear rotor size: 303mm 23mm

As you can see.... the new na2 nsx-r is using the old nsx-r caliper size. ALSO, the new na2 nsx-r is using the old nsx rotor size!! Mother Honda went back to a larger piston is understandable, but why they go back to the old rotor size is beyond me?!

They must know something that we don't!

Henry.

 

[s2ktaxi]

As you can see.... the new na2 nsx-r is using the old nsx-r caliper size. ALSO, the new na2 nsx-r is using the old nsx rotor size!! Mother Honda went back to a larger piston is understandable, but why they go back to the old rotor size is beyond me?!

They must know something that we don't!

Henry.

First, are we sure those specs are right for the new NSX-R?

If they are, it's all about weight... There is less mass to stop in the NSX-R, so the older rotor size may have been adequate for the lighter car. As for the pistons, who knows...

 

[JJCNSX]

I am planning on making 97 brake conversion kit.. "bracket"

meaning, you can still use your own calipers & brake pads, just need oem 97+ rotors and "bracket"

anyone interested? let me know, if i gather enough interest, then i might proceed..

http://www.nsxhelp.com/diy2/Real-World Brake Upgrades.htm

i am sure this will be the most cost effective upgrade!

thanks

-jjc.

 

[kenjiMR]

what do you guys think about using BBK up front and using OE rear rotor?

Does anyone have DIY or rear caliper adapter that allows using stock caliper with a increased diameter rotor?

I'm thinking about first getting Stoptech BBK up front and get the rears later on.

 

[zoomnsx]

SOS sells the rear bracket and big rotor

 

[Craig]

Latest on Brake Zone Wilwood Kit

Photos of the final fitment before production.

#1 Kit Front as pictured with OEM Rear Caliper over 13" rotors.

 

[Craig]

Kit #2 Front and Back as pictured.....Stay tuned for release dates and pricing info (which your going to like) And yes that's an E Brake

 

[Ponyboy]

what do you guys think about using BBK up front and using OE rear rotor?

Does anyone have DIY or rear caliper adapter that allows using stock caliper with a increased diameter rotor?

I'm thinking about first getting Stoptech BBK up front and get the rears later on.

Kenji, the front only BBKs are designed with using the OE rear rotor. So kits like Stoptech's take this in mind when they offer them up for sale. I'd think if you needed more rear bias you could get some with a more aggressive pad in back. BUT the front only kits should be proportioned correctly from the factory.

I just installed the front Stoptech kit yesterday. Looks good - will provide photos tomorrow. Did some weight measurements and the Stoptech caliper is actually lighter than the OE caliper - by about a pound. Kinda cool.

 

[nsxtasy]

the front only kits should be proportioned correctly from the factory.

Better yet, they should provide an adjustable proportioning valve.

 

[Ponyboy]

Better yet, they should provide an adjustable proportioning valve.

A porportioning valve is useless if the brake system is already porportioned correctly from the brake kit manufacturer. Plus, it's an added expense passed onto the consumer b/c of inadequate research and testing.

EDIT: StopTech Slide Show

 

[nsxtasy]

A porportioning valve is useless if the brake system is already porportioned correctly from the brake kit manufacturer.

Not true. The need for proportioning can vary, depending on factors that can change (like which brake pads you're using at each end of the car).

Plus, it's an added expense passed onto the consumer b/c of inadequate research and testing.

Actually, it's a fairly minor expense and has nothing to do with research and testing.

 

[Ponyboy]

Not true. The need for proportioning can vary, depending on factors that can change (like which brake pads you're using at each end of the car).

That's silly. The supposition is that the vehicle has the same kind of pads on all four corners. Just like it's supposed that the car has the same kind of tires on all four corners. Do we need to list a set of parameters including weather conditions as well? Sure it's true. If the brake manufacturer uses the correct piston diameter (read: designs them correctly) for a given vehicle, a proportioning valve isn't needed.

Do I need a proportioning valve?

Excerpts taken from the SoS site:
"The kits currently available use off the shelf components with designs not taking into account the unique braking and weight balance characteristics of the NSX. Adapting these components often lead to compromises such as deletion of the emergency brake and the required use of proportioning valves to regain some of the braking balance lost."

"Unlike other kits available that require proportioning valves to compensate between too much front bias, the weight characteristics of the NSX were calculated into the design of a package that achieves optimal front/rear braking torque balance."

Regarding the SoS Brembo Gran Tursimo kit:
"This kit addresses the two negative aspects of the Brembo Gran Turismo kit. This kit eliminates to purchase the costly replacement Brembo e-brake ($995.00) and maintains proper braking balance eliminating the need to purchase proportioning valves ($325.00)"

Actually, it's a fairly minor expense and has nothing to do with research and testing.

Actually, a fairly minor expense is still an expense. If it's minor or not depends how fat your bank account is. You could almost buy two sets of new CAT bypass pipes with $325! So research and testing have everything to do with it.

 

[nsxtasy]

That's silly. The supposition is that the vehicle has the same kind of pads on all four corners. Just like it's supposed that the car has the same kind of tires on all four corners. Do we need to list a set of parameters including weather conditions as well?

No, but that's exactly the point - things ARE different at different corners. You know as well as I do that there are a lot of different parameters that can affect braking. Not every car uses the same brake pads at both ends. I'm trying different brake pad compounds all the time. And I don't change the compound at one end, when there's plenty of pad material, when the brake pad wears out at the other end. Do you? Have you always used the exact same compound at both ends of your car? I doubt it. Most track rats haven't.

I'll give you an example of another variable. I have brake cooling ducts to the front brakes on my NSX. Doesn't that mean that I have a different need for front-to-rear bias from an NSX that doesn't have such ducts? Doesn't that mean that I have a different need for front-to-rear bias from DanO's NSX that has ducting to the rear brakes? All of which results in the need for front-to-rear biasing that may be different from one car, to another car, to another car. And no amount of research can test for every possible front-to-rear variation that can occur on a car. You know that as well as I do, so there's no need for silly statements about the need for research. The fact is, a simple, inexpensive proportioning valve eliminates the need to worry about research or testing for all the variable parameters on different cars.

a fairly minor expense is still an expense.

First of all, that $325 figure is bogus. I don't think a proportioning valve costs that much, except in the eyes of someone trying to hype a kit that doesn't include one. Regardless, that's a tiny expenditure when compared with the cost of a big brake kit at both ends of your car. If you're spending lots of bucks - you're talking about a front-and-rear big brake kit (obviously, since you are talking about controlling the size both front and rear), you're talking about spending $4-5K on the kit, plus another $2-4K on bigger wheels, plus tires - so you're talking about spending $7-10K. The proportioning valve is less than 5 percent of your total expenditure. By comparison, that is truly minor.

If it's minor or not depends how fat your bank account is.

If you are going to put it that way, then you must also consider this - if $325 for a proportioning valve is a major expense for your bank account, then there's no way you would be considering $7-10K for a four-wheel big brake kit with bigger wheels and tires.

You could almost buy two sets of new CAT bypass pipes with $325!

Why, so you could put twice as much pollution into the environment?

So research and testing have everything to do with it.

That's nonsense, for the reasons noted above.

I'm kind of surprised at your response, Ponyboy - you're usually more knowledgeable about these things...