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From the Wilwood site, searching the plate number, then broken down into the pad information:

78XX plate information:
7812 pad
7812 pad
0.49" thick (pad material plus backing plate metal)
2.21" total height of the backing plate material , pad slightly shorter

71XX plate information:
7112 pad
7112 pad
0.49" thick (pad material plus backing plate metal)
2.36" total height of the backing plate material , pad slightly shorter

There is an issue with the cross bar holder positions of these two plate options.
This caliper shown uses the center bar to hold the pads down. The cross bolts I found online have a sleeve (that cover the bolt side to side) that provides the pressure downward on the pads. Anti rattle is basically from the pressure springs, front to back, per plate. Some designs use a spring wire for this function, we will see what Wilwood says about this.



I will update the pads listing to show the part numbers for the 71XX plate using the 7112 pad.

Edit 2015 March 24. Updated the pads listed here in the pics. These calipers are supposed to come with a cross bar where the large cotter pin is located.

Here is a picture to show the cross bar issue using an unknown set of Porterfield pads/plates.

Must be a different pad backing plate because it has room to drill out the center hole, but there should not be on a 78XX/7812 pad set.

78XX/7812 are listed as the pad for this billet Dynalite caliper. Forged Dynalites move to the 71XX/7112 setup.

Different mounting sequence for each style but they oddly enough have a similar bar across the center. If someone could tell me the exact dimension from left to right and top to bottom, of where they bar resides, we could lay to rest whether you can fit 7112's in the Billet Dynalite caliper, and if you simply use a cotter pin setup to retain them.

I obviously prefer a bolt/nut setup and it provides further cross support in the center of the caliper, maybe not such an issue of reinforcement with the forged model by strength of design.



Some more pictures of the kits as they start out in life:

LilEvo is using a slightly different caliper than I will be receiving.

We were both wondering about the 7812 or 7112 plates/pads and which one to use.

I will be receiving the Billet Dynalite side inlet 120-5081 calipers.
LilEvo is using this Click for pic of his calipers, the Forged Dynalite caliper to match the 120-5081 specs for rotor clearance.

Those specs are as follows: rotor dimension 0.38", rotor top to bottom diameter 13.06", caliper mounting centers are 5.25"
Forged Dynalite Caliper 120-6818

LilEvos' caliper 120-6818:


Side inlet Dynalite 120-5081


Forged dynalites are lighter by 0.3 lbs per caliper. Difference between 3.7 and 3.4 lbs.

I updated the postings with the kit shown well above this post. March 25/2015

The more I look into it, the more I have to re-read what pads fit which caliper.

7812 pads fit the billet Dynalite calipers. Looks like the cross bar is a support, and it works to hold the pad down/locate it top/bottom.
The anti-rattle comes from the pressure tangs/clips you see x4 at either side and end of the caliper; they contact as the pad slides in.
7112 pads use the bar in the center, or a long cotter pin type thing to keep them retained, and it does feed through the raised hole on either caliper half.
7812 and 7112 pads are both physically the same length, but the are retained differently.
I am not sure why the 7812 pads are used in the Billet Dynalite, because they show two holes at either end of the backing plate, but they don't appear to be held in place/located
by those two holes and a corresponding set of retainer bars.
Sounds like a design compromise whereby these pads/plates are used in many applications.

What brake lines should work with this caliper?

I would like to list here which brake hose kit (stainless style kits) will fit with these (Wilwood 4 piston, side mount brake fittings) calipers being installed on the C53A with rear calipers and the C60/70 sedans with drums/discs. Anyone using a converted AWD setup, will not find this portion all beneficial because the calipers and spacings will need to be measured, might not be a direct application crossover, meaning one style and fitting front and back.

Is the direct crossover, the FWD DSM 1G ?

I am using 1991-1992 Galant VR4 front brake hoses and they are a direct fit for stock C53A calipers.

Pretty sure my rear replacements, in rubber, are FWD DSM 1G lines .... but want to confirm.

This is the drilled fitting size on the side of each caliper half: Inlet Thread Size: 1/8-27 NPT

Has anyone used the DSM or GVR4 front rotor backing plates with the Wilwood's in place ??

I'm about to put my hubs back together and think that although the rotor is now sitting further from where the backing plate would traditionally sit, I have no way of confirming how far inboard the mounting lugs differ between the CSM/GVR/TEL versions of hubs.

It's been so long! If you need any measurements or anything let me know. Wish I remembered what part number the brake lines were.

I'm on the fence about trying to install the backing plates. They would ultimately require some trimming and rust preventative measures/re-paint, but it would be nice to have some backing plates that do not require the hub to be removed, for them to be fit in place. I seriously wish I had a set sitting around here ... the knuckles are painted, races in place and are ready to accept the bearings/hub/seals.

I did notice the front hubs do use two different seals, brown (sits right at the back side of the hub when it is in place/pressed in), and the black (accepts the outer cv joint). I even took pictures of the instructions that were shipped with the brown outer seals. I got OEM parts only, to use with the 1992 knuckles/hubs I sourced from my parts car. Complete 1989 knuckles/brakes C53A come off, complete 1992 knuckles/brakes C52A going on.

Backing plates do not grow on trees around here ... as they usually turn to dust when you find them on cars, older than 7 years with our climate and salt doing their best.

Okay, back to the brake line question. Mainly what brake line connects the front caliper to the chassis side hard line.

I want to make sure the line used is professionally secured to the strut body, so if the answer to my question is much like the line I already have, then it is a compromise.

I have to replace one of the lines I got in the mail cause it has a pinch/crush of the tubing at the caliper side fitting.

My lines look like this:



Anyone have a picture and close dimension of the their front brake line being used?

Caliper side fitting would be 1/8-27 NPT, and the chassis side would be the standard Mitsu brake line threaded end. The long line pictured above.

I don't want to compromise if I don't have to with brake system hose. I have to custom order to replace the long line anyways, so I might as well replace everything front to back at that point.

Ninja Edit: Maybe I can use the other pair of lines I have shown in combination? I just realized the other shorter line with the 1/8-27NPT fitting, would work but would have to curl back towards the strut quite a ways. I can test fit it in the wheel well, but I would only go that route if it looked like the line was under no stress and it would not be contacting anything under full lock inboard.

So, looked online and found a master cylinder choice that should have the lines fitting up in the exact same place as stock C53A masters would have.

1992 Mitsubishi 3000GT booster using 1-1/16" and 1989 Mitsubishi Mirage 1.6T have the same fitment.

Here is the big question!

I compared pictures of the two from the same angle and it appears that the top bottle uses the same spacing for the "feeds" and the retaining pin (holds it to the body of the cylinder.

If this is true, can anyone confirm performing a bottle swap between the two?

If I don't have to order one with a new bottle, I won't, I'll just transfer it.

Never hurts to ask. I'll know what my options are very shortly for ordering parts from WorldPac on this side of the border.

2G AWD master works fine too and has extension hoses so you can mount the bottle wherever you want.

I suppose you could also just buy that adapter and hose kit and use it on whatever master you wanted.

http://lilevo.com/pictures/cars/current/engine_aug.jpg

Great info right there!

I'm sifting through some other basic knowledge questions regarding master cylinders, mainly ABS and Non-ABS differences, if any.

RTMRacing has 1G DSM masters listed as ABS style, superceding all NON-ABS or being 100% equivalent. So, does this ring true to 3000GT masters of the 1-1/16" variety?

Diamante (1"), and 3000GT VR4 (1-1/16") all have proper fitment for re-using the stock lines, whereas GVR4 (1") and 2G NON ABS (15/16") ABS (1"), would require at least on line to come from the other side of the cylinder or both straight up. Not a big deal to fabricate a line, granted. I need to sit down and see the math behind the area of on caliper and how much fluid/pressure is being moved and exerted at the pad on either side of the rotor now, given various master cylinder bore diameters and assuming pedal ratio and brake booster assist remain constant. I see positive reviews of dual piston setups using 1" Masters like the Diamante, so I am thinking if the Wilwoods have as much surface area at the 4 pistons as do the 3KGT VR4 4 piston calipers, then it would make sense to use an appropriate piston size such as the one from that application. Brake booster ratio is much lower on the C53A/Elantra boosters (4:1) versus the 3KGT VR4 booster ratio of 7+:1 or dual booster ratios still higher yet due to ABS components. If two systems were setup exactly the same (rotor/pads/pedal ratio/etc) but the booster was lower on one car, then it would apply less force by nature of assist. This can still be fine for a lighter car, I hypothesize.

What is the booster ratio on a 4G CSM? It seems like when I switched from a 3G to 4G booster I lost a lot of assist. It seems like the pedal takes more force to do anything.

I found a bunch of good info some time back, and collected it into one thought process.

http://www.4g61t.org/forum/posting.php? ... 2&p=300492

British 92-95 Mirage was listing 1.3/1.6/2.0D engines with 4.5 or 6:1 (ABS) booster ratios, same for the PDF FSM listings for 93-96 Mirage (I assume USDM/CDN).

I think the larger the total surface area of your caliper pistons, considering the small size up in master cylinder bore, the more booster pressure (and heavier weight the cars equipped with them were) was equipped on the cars. Watch out for ABS boosters that were listed as a dual circuit style, because that gives different booster ratio front and back! Just to add to the confusion. It's tuning your brakes, as if tuning the engine wasn't finicky enough.


Maybe the fulcrum point or lever ratio is different inside the 4G chassis and this equation is thrown slightly out of whack.

Engine vacuum will directly affect your brake booster operation and how much "draw" it is able to work with as you enter decel and stomp on the pedal. With a car running low vacuum (cams/tuning or other maladie), sitting at the traffic lights or low speed operation can be drastically affected. Race track with high RPMS and throttle snapping shut, can yield high vacuum readings, but city driving likely won't if the car isn't setup for that environment. It has been a long time since I have been thinking about variable like this. Main reason I tried to stay with mild cams, and keep my vacuum leaks off the chart. Now my master leaking out fluid past the rear seal, has me worried about the booster. I'll check it visually when the master is off, but a booster function check is pretty easy to perform.

Put foot on pedal and start engine. Pedal should drop a little bit and stay at that level with continued effort at the same output.
Foot still on pedal, shut off engine and pump pedal until it gets really stiff and no longer provides added boost effect.

If the pedal dropped + stayed at point one = good.
If the pedal got really stiff to move after 1-3 pumps, then = good.
This proves the booster can provide boost/hold+allow use of vaccum. Check valve should be good if vacuum is held in the booster after engine is shut off. Remove hose and it should allow a "whoosh" noise as air enters back in quickly!

LILEVO, what is your master cylinder diameter? 2G Eclipse ABS or NON ABS? What year range?

What I am seeing as I look across the spectrum is this trend:

Small sedans/hatches (Colt/Mirage) 13/16" or 14/16" with single piston calipers front/cylinder rear - PRE ABS
Mid size sedan (Galant + GVR4) 7/8" to 1" ABS, single then dual piston calipers, larger bores always paired w/rear calipers
Sports cars (DSM+3000GT+3000GT VR4/EVO 5-6) 1" to 17/16" or 1-1/16" for quad piston brembos

So, I have not applied the math to the quad piston Wilwoods yet, but I thought it would be safe to go with a 1-1/16" master cylinder setup for fluid transfer on the first pump.

I drove a 2002ish Impreza sedan with WRX Brembo big brakes. It did not have the master cylinder upgraded (nor brake booster assuming it was different also) to match the four corner brake multi piston setup (4 per front caliper, 2 per rear).

Each first pump (yes, there is time to bleed back/lose "prime/pump up" due to the seals retracting) was half way to the floor and after that it would firm up, but performance appauling. Granted I replaced all the pads and rotors with what the guy supplied (his were all rotted upon arrival), and even bled one caliper tilted up in the air becausee he had two "X side" calipers installed. Needless to say I had to use old pads to keep the pistons at bay during the bleed of the upturned culprit.

This is part of the reason why I am taking my time to get all this together and show people what they should be thinking about when they take on something like this.

If we had a complete system, plug and play, that would be fantastic. Instead we have to use our heads just a little to confirm proper accomodations.