vendetta

So im looking at these Wilwood D52 Calipers

http://www.wilwood.com/CaliperList.a...0Dual%20Piston

and im just checking, 1990 Camaro iroc, used D52 pads/calipers stock right?

im hoping to just do a direct replacement, with some D/S rotors , stainless lines ect

but i guess these are a few pounds lighter and have a lil over double the orginal stoping power

thoughts?

//<86TA>\\

iTrader: (15)

you wont have double the stopping power, the pistons are smaller. You will see an improvement over the old stock parts, but its not going to be earthshattering.

what do those cost anyway?

vendetta

sorry ment to say the area thats actually compressing, having dual pistons

there not overly expensive at all, i was originally going to get there front brake kit but im going with these guys now,

RBob

iTrader: (1)

Nope, our 3rd gens use a metric caliper. A D52 will not fit the stock spindle. Wilwood provides the dimensions of the caliper, easy enough to pull a wheel off and do some measuring.

The D52 is a popular caliper. GM used it on many vehicles. IIRC it was first used in the late '60s.

RBob.

RBob

iTrader: (1)

The Wilwood D52 calipers for the front brakes have 20% more piston area then the stock 3rd gen metric caliper. So there will be more braking capacity. Can get these calipers for about $160 each. They will also be available in black in the near future.

RBob.

vendetta

so they wont fit my car though?

RBob

iTrader: (1)

Uuh, check a few posts up...

RBob.

vendetta

how much of a difference in there between front and rear calipers?

does anyone make a rear kit?

RBob

iTrader: (1)

Which front and rear calipers? Stock, LS1, 1LE, D52's. 99.9% of this info is on the 'net.

Many kits are available for rear disc set ups. Best bet is to grab a set from an LS1 f-body and bolt them on.

RBob.

vendetta

the stock ones, i took a poke around on here but didnt find much

RBob

iTrader: (1)

There is a lot of difference between the front and rear calipers. The biggest being the rear caliper has a parking brake mechanism. The second being the piston area.

Then there are two different front calipers used in 3rd gens, along with 2 different rear calipers used in 3rd gens.

Fronts:

1) a cast iron single piston floating caliper was used (stock brakes)
2) an aluminum dual piston guided pad caliper was used (PBR, 1LE brakes)

Rears:

1) a cast iron single piston caliper was used
2) an aluminum single piston caliper was used (PBR)

RBob.

vendetta

do you know of any aftermarket rear kits that arent uber expensive? ive been poking around and am only find ls1/corvette kits for 900-1500 bucks.

fastcars

Thirdgen camaros with the standard 10.5 inch rotors
used the metric D154 calipers.
Wilwood and other companys offer this caliper with a larger
piston than stock but no dual pistons calipers are available to
my knowledge.

vendetta

ive been looking around on willwood/SSBC and a few others and have found nothing

vendetta

talking about these maybe?

http://www.wilwood.com/CaliperList.a...ingle%20Piston

fastcars

The caliper at the top of that page is the D52.
The 2 models of calipers below that are the D154
or whats called the GM metric calipers. They will
bolt on to our cars.
The D52 and D154 designation is actually the
generic part number for the brake pads.
You can also find similar calipers made by Howe
and US Brake. Look at the circle track racing stuff.
Alot of racing classes require these guys to run
OE brakes but if you're not cheat'n you're not racing.

fastcars

Sorry, I stand corrected. It has been brought
to my attention that stock replacement dual
piston calipers are available for thirdgens as
a bolt on.
Check out SSBC part number A181 or Summit
racing has their own under part# SUM-BK181.
Price is a little high but if you don't want to
cut up your spindles and just want something
a bit better than stock, this is a good alternative.

vendetta

yes i have looked at those, im just concerned with finding a rear set up, owuld have to have the E-brake and everything.

Timinsk

iTrader: (9)

Would these be the only direct "bolt-on" calipers that would be making a clearance on a stock setup? or are there others?

RBob

iTrader: (1)

Be careful before going with these calipers. They have a lot less piston area then the stock calipers. 3.5 sq-in vs. 5.0 sq-in for the stock ones.

Which means for the same clamping force 42% more foot pressure on the pedal is required. So instead of 100 pounds of foot/leg on the pedal, 142 pounds of foot/leg are required.

With an aggressive enough pad material this can be made up for. But at the cost of a faster wearing rotor and a more expensive brake pad.

RBob.

vendetta

5 sq in seems really big

RBob

iTrader: (1)

Are you stating that I did the math wrong? Or that you don't know how to do the math?

What did you come up with for piston area?

RBob.

fastcars

Very good point RBob,
I never looked at the total area of those pistons,
Who needs 2 little ones when you can have 1 big one.
So the large diameter OE caliper is the way to go in this application.
Stock=2.38" diameter or 4.45sq-in.
large (Wilwood and other companys)=2.75" diameter or 5.94sq-in.
Thats a 25% increase in clamping force using your example.
$340 for a 42% decrease in braking performance. Sounds like a
great deal to me.

SSBC should maybe hire a new engineer,
or how bout a new marketing team to tell us why those 2 little
pistons are so much better.

RBob

iTrader: (1)

Yes & no. You mentioned 2.38" pistons on the stock caliper. This isn't true where it counts. The piston necks down to 2-3/8" where it meets the pad. But isn't what matters when it comes to clamping force.

The piston diameter at the seal is 2.52" for the stock 3rd gen metric caliper. So it is a 5 sq-in piston area. Pull back the dust boot and check it out.

As for single vs dual pistons, generally speaking, the more pistons the better the "feel." This is the feedback the driver gets from the brakes. The greater number of pistons spreads the load over a greater area of the pad.

This means less pad deflection and a better sweet spot.

Agreed, SSBC should leave the engineering to engineers and leave marketing to those that understand braking systems.

RBob.

vendetta

oh not at all, just picturing the difference in my head , seemed odd

and yea why would they even bother producing these smaller ones? i get the dual piston spreading the clamping force more evenly but is seems like a bit of a waste for not much gain.

im probably just going to get some new OEM rear calipers and get willwoods front brake set up. should be sufficent for a DD and some racing id say. i just prefered a more balanceed system but cannot afford two 800-900 dollar kits

RBob

iTrader: (1)

and yea why would they even bother producing these smaller ones?

That is a good question that I can only agree with. Several years ago I looked at them and came to the same conclusion. What are they thinking?

As for an upgrade, you don't necessarily need to buy a kit. Although I did some of the work myself I was able to piece together a front set up. It is the 4th gen Corvette standard duty parts ('86 - '96).

Purchased the rotors new (12" x .81", rear). The calipers and abutments from a salvage yard. These were actually in decent condition with fairly new PBR pads. Did the stock rotor to hub mods myself. And had the calipers brackets made locally.

Then did the spindle mods too. Best to remove them from the car for this. I did one on the car and decided to R&R the other side for an off the car mod.

Note that this was many years ago before these mods and pieces were available elsewhere.

But it doesn't mean that they still can't be done DIY.

The 12" C4 standard calipers have less piston area then the stock calipers. But the increased rotor diameter makes up for most of this. So in the end the pedal pressure is about 5% more for the same clamping force.

But the better feel and lower fade more then makes up for this. I've said it before, and I'll say it again, these are the brakes that should have been stock on our 3rd gens...

And behind 15" wheels, it is all rotor. So the looks are also there.

BobR.

fastcars

[quote=RBob;4509944]Yes & no. You mentioned 2.38" pistons on the stock caliper. This isn't true where it counts. The piston necks down to 2-3/8" where it meets the pad. But isn't what matters when it comes to clamping force.

The piston diameter at the seal is 2.52" for the stock 3rd gen metric caliper. So it is a 5 sq-in piston area. Pull back the dust boot and check it out.

Thats interesting, good to know when making a comparison.
The specs I wrote are well published by several manufactures
(Willwood, Howe, US Brake, etc.)
Never assume anything I guess.
And you are definetly correct, we have more choices than most
these days for brake upgades. LS1 and Corvette brakes can be
installed for very little money if do some research, shop around
and use some ingenuity.
Worth every bit of the effort

vendetta

[quote=fastcars;4510121]
i did like the idea of the vette/ls1 replancement, but the supply of there parts is very limited around here, in fact ive never even found a V8 Camaro/firebird in the junkyard and no one seems to part out stuff round here.

i was really hoping for just a lil bit of a boost to my braking as per my slighlty abover average speeds lol

vendetta

what would you guys say is the most cost effcient brake kit out there besides the vette/ls1?

and have either of you upgraded the rears? what did you use?