The Mugen brake kit thread got me thinking.

Do we know the total piston surface area for the popular caliper upgrades?
It would be nice to compare in one place - can anybody fill these in:

Total Piston Surface Area:
Stock:
Spoon:
NSX:
Mugen:

others?

 

Isn't the pad surface area and rotor size most important?

Stock = Spoon = NSX in terms of pad area

Stock = Spoon = NSX in terms of "swept area" on the rotor

NSX > Spoon/stock in terms of rotor thickness and heatsink capability

In terms of total piston surface area I think it would be Spoon>Mugen>NSX>stock ?




Modified by Big Phat R at 8:10 PM 12/30/2003

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Big Phat R &raquo;</TD></TR><TR><TD CLASS="quote">In terms of total piston surface area I think it would be Spoon&gt;Mugen&gt;NSX&gt;stock ?</TD></TR></TABLE>

You think the Mugen single piston would cover more surface area than the NSX's dual piston?

Cudos to Flux on an interesting topic

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Big Phat R &raquo;</TD></TR><TR><TD CLASS="quote">Isn't the pad surface area and rotor size most important?</TD></TR></TABLE>

No, according to this good at StopTech it is the diameter of the piston that is most important to clamping force.
http://www.stoptech.com/whitep...1.htm

"Clamping force can only be increased either by increasing the line pressure or by increasing the diameter of the caliper piston(s). Increasing the size of the pads will not increase clamping force."

 

Well, the Spoon calipers have 42,85mm and 38,18mm pistons, so total area for each caliper would be: 22,9cm2 + 28,84cm2 = 51,74cm2 (8,02in2)

 

"The effectiveness of a caliper is also affected by the stiffness of the caliper body and its mountings."
acording to this, spoon caliper&gt;.mugen,nsx,stock
spoon calipers are solid mount in the hub, while mugen are floating design,

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Big Phat R &raquo;</TD></TR><TR><TD CLASS="quote">In terms of total piston surface area I think it would be Spoon&gt;Mugen&gt;NSX&gt;stock ?</TD></TR></TABLE>

I don't know.

What I do know is that these are the piston diameters for the NSX:

'91-96: Front 40 mm and 36 mm; Rear 43 mm.
'97-04: Front 40 mm and 34 mm; Rear 48 mm.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nsxtasy &raquo;</TD></TR><TR><TD CLASS="quote">

I don't know.

What I do know is that these are the piston diameters for the NSX:

'91-96: Front 40 mm and 36 mm; Rear 43 mm. Total front piston area: 22,745cm2 (7,05in2)
'97-04: Front 40 mm and 34 mm; Rear 48 mm. Total front piston area: 21,645cm2 (6,71in2)
</TD></TR></TABLE>

So it's Spoon&gt;NSX as a start.

Edit: forgot that NSX calpiers are 2 piston, numbers are corrected.
on me


Modified by 99ITR#3715 at 9:23 PM 12/31/2003

 

Anybody know off hand the size of the stock ITR piston?

 

Allthough this is a bit off of the topic.........I find it very interesting that BMW uses single piston calipers for most of their vehicles including M cars.... Not really sure what this means, but they seam to have no problems with single piston brakes

 

I don't have a stock caliper handy to measure, but the single S2k (same as Mugen) caliper is measured out to a diameter of 53mm (the best I could stick the Mitutoyos in there) so that nets an area of 22.05cm^2.

--
George

 

I believe the NSX is a dual piston caliper so the area is 1/2 of what you calculated or: 22.73cm^2.

Edit: Still doesn't change the result of Spoon&gt;NSX

Edit: For post '97 NSX calipers, the area is 21.63cm^2

Edit: Math error above...

--
George

Modified by geometro at 11:43 AM 12/31/2003


Modified by geometro at 11:45 AM 12/31/2003

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EbboyPSi &raquo;</TD></TR><TR><TD CLASS="quote">Allthough this is a bit off of the topic.........I find it very interesting that BMW uses single piston calipers for most of their vehicles including M cars.... Not really sure what this means, but they seam to have no problems with single piston brakes</TD></TR></TABLE>

I\Funny you mention this. I was reading EVO just last night and they were cursing BMW up and down - saying it was unacceptable t0 use single piston calipers on the M3 and the M3 CSL.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Flux &raquo;</TD></TR><TR><TD CLASS="quote">

I\Funny you mention this. I was reading EVO just last night and they were cursing BMW up and down - saying it was unacceptable t0 use single piston calipers on the M3 and the M3 CSL.</TD></TR></TABLE>

Yeah, Ive never really understood why bmw doesn't use multi-piston calipers. However, I have seen their brakes raved about time and time again. That article in EVO is one of the first times I've heard that complaint.

EVO magazine is one of my favorites btw

 

No, but the Accord Wagon & V6 (through 02), CL V6, 93-96 Prelude VTEC, 97-01 Prelude (non-ATTS) all had the same front calipers so someone has to have one lying around they can measure.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Flux &raquo;</TD></TR><TR><TD CLASS="quote">Anybody know off hand the size of the stock ITR piston?</TD></TR></TABLE>

 

Ok, after pouring through zerosearch...ITR piston size is 57mm, that nets 25.50cm^2.

--
George

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by geometro &raquo;</TD></TR><TR><TD CLASS="quote">I don't have a stock caliper handy to measure, but the single S2k (same as Mugen) caliper is measured out to a diameter of 53mm (the best I could stick the Mitutoyos in there) so that nets an area of 22.05cm^2.

--
George</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by geometro &raquo;</TD></TR><TR><TD CLASS="quote">Ok, after pouring through zerosearch...ITR piston size is 57mm, that nets 25.50cm^2.

--
George</TD></TR></TABLE>

thanks for the info... are you sure the itr caliper pistons are bigger than the s2k caliper pistons, then? is the 53 mm piston size correct for the s2k? anyone verify this?

 

Keep in mind that piston sizes are not necessarily the best indication of the quality of the braking system. Maybe clamping force... but remember, once the clamping force is sufficient to induce wheelspin/ABS - which it is, on all these cars - the limiting factor in braking distance is the tires, not the brakes.

I would think that the size (diameter/thickness) of the rotor is at least as important, since that gives a measure of heat tolerance (dissipation ability), which is what becomes more important once you're pushing the brakes hard....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nsxtasy &raquo;</TD></TR><TR><TD CLASS="quote">Keep in mind that piston sizes are not necessarily the best indication of the quality of the braking system. Maybe clamping force... but remember, once the clamping force is sufficient to induce wheelspin/ABS - which it is, on all these cars - the limiting factor in braking distance is the tires, not the brakes.

I would think that the size (diameter/thickness) of the rotor is at least as important, since that gives a measure of heat tolerance (dissipation ability), which is what becomes more important once you're pushing the brakes hard....
</TD></TR></TABLE>

Completely agree - but right now I am interested in comparing piston surface area...