ok i did some searching and didnt find info to my hearts content...so here are my questions

what is required for a single to 4 piston caliper brake swap. I have an 89 GTU and would like to put a set of 4 piston calipers up front. i know i need the calipers (duh) and saw it mentioned that i would need the brake lines with them. so far this is corret right?

now should i get new 4 piston calipers (400 bucks per caliper from a place like mazdatrix is kinda steep for me), or would i be better off getting a scrap yard set off of a GXL or T2 and doing a rebuild for them?

ok well of course new rotors would go with this and since i will be doing only street driving i would not want or need slotted or cross drilled (right?). question: do the 4 piston brakes use bigger discs than the single pistons? also, i should probably just get a new set of rotors for this and not try to find a scrap yard set right?

last part: would a master cylinder change also be necessary for this job? or can the GTU master handle the new 4 pistons.

and the biggest question of all: would this would be worth doing or would it depend on which parts i could get used and how much they cost me.

 

Peep out the for sale thread. Banzaitoyota has a full conversion for $150.00 :-)

 

my car is an 89 and has 4 piston calipers up front... i thought they were standard... i dont know what trim i have what trim came with 4 piston calipers?

 

Just make sure the ones that you get dont have the pistons rusted to hell. But if your rebuilding, i guess thats no problem. Also, You dont need all those crazy springs that put posive pressure on the pad, you can go to you local hardware store and pick up normal springs that slide over those 2 pins on the back of the caliper for around 40 cents each.

 

^ bump, saw thread after i posted on mine

 

If you've done the search, you know already, I found 6 threads on S5 swaps alone.

You need the front calipers, the brake hardlines. Rotors are the same size and thickness, no concern there.

For the rear, you need the calipers and the vented rear rotors.

You can buy 4 piston calipers rebuilt for ~70/ea at the hardware store. The rears are far more expensive, better off rebuilding those.

You'll have to judge for yourself on how good a swap this is.

 

for Rs4Racer:
the base model for 89-91 is the GTU, which i believe came with the single piston calipers. the GXL, GTUs, and T2 all came with 4 piston calipers. if im wrong someone can correct me

 

Are you ssuureee the rotors are the same size? Im not doubting you, as i have no hard evidence other than "just looks bigger". When i had the 88GTU the front rotors looked huge, on my 86 base they look pretty small. I dont think the 86 14" wheels would fit over the 88GTU's rotors (of course, if the bolt holes would match up). And arnt 5 lug rotors just plain beefier than 4 lug?

Correct me if im wrong. Thanks

 

OK. so I'm doing a 5 lug conversion with the GXL brakes to my 87'base. I just was thinking, would I need the master cylinder also from the GXL?

 

And another thing, i thought all rear brakes were single piston, just the "upgraded" brakes had Vented rotors and that was the only change? Man.. i hope im not completely lost. Thanks

 

nope, silkworm just posted on that

 

Yes, I'm sure about the front rotors being the same size, the FSM lists the specs at 10.87" diameter x .87" thickness for both Type A and Type B rotors, ON S5 cars only. S4, yes, they're different sizes.

The rear brakes, not totally certain on the caliper, but they list the rotors as being slightly different diameters (10.28 for Type A (single piston front), 10.75 for type B and Turbo. That would mean that the calipers probably would need to be different, but I'm not totally certain.

PaulC

 

Ah, ok, i see now. All the Sevens i deal with are S4s Thanks for clearing that up.

 

Well....if anyone needs a full set (no hubs), I have it.

4 - used rotors (all vented)
FRONT
-front are near perfect, just need resurfacing
-I compared the to my new rotors, not much wear
REAR
-mostly worn on the inner side (normal)
-not warped
-can be used on w/another set of pads
4 - Used calipers
FRONT
-clean, well dirty from use w/stock line-hose
REAR
-same
-has lines but no bolt to attach the line
-used them form my new lines

All parts are boxed in the boxes from all my new parts. I can shipping them using UPS or USPS. UPS ground is aprox $25. USPS will be in the range of $50. These rates are for shipping to So.Cal.

MAKE ME A REASONALBLE OFFER!!!!

 

Not only steep, but retarded to boot. That's near the price of a big brake upgrade kit.

 

I did a conversion on my 91 NA (don't know if its a GLX, GTU or what), it has P/W, P/S, P/L, sunroof, heavy *** hood, non LSD, and sinngle calipers.

No need to change the discs, however the rear ones on the single pistons FC's have a solid rear disc vs the double pistons caliper FC's that have a vented one.

All 5 lugs FC's use the same brake pads........

As mentioned before, you need:

- Front Calipers
- Brake lines
- Hard lines (it goes in between the caliper and the brake lines) <----- you can make your own

It is a very easy job, I went thru and got myself some nice HAWK HP (the cheapest ones), and braided lines. My car stops on a dime, I LOVE IT!!!

The only thing I don't really like is the squealing, but once I hit the brakes....................It's all forgotten

 

ok, so for brake swap you don't need hubs?

and brake lines are absolutely needed and BMS's aren't...? just clearing things up.

 

on s4's the rear are different, the calipers on standard brakes are smaller as well as the rotor not being vented. I have had to fit a standard rear caliper on a vented rear rotor. They fit but have to have thin pads!!!!not a very good fix.

 

ok i got the calapers with the hard lines will the hard line hook up to the old single piston lines from the shock.

 

Bump please anyone need info Quick
do you konw if single piston brakes will use the same line if i were to put 4 piston calapers on my car i got the hard liine on the 4 piston calalper will it adapt to the existing brake line attashed to the shock.

 

When I did my swap from the 4-lug single piston to 5-lug 4 piston, I was told I needed the proportioning valve from the 5 lug car. If I didn't, the front-to-rear braking balance wouldn't be correct. Also, I was told that I needed the booster from the same car, as it is a little larger. But I think the master cylinder itself is the same for either brake setup.

 

The hard lines that comes with the 4 piston calipers will replace the strut-mounted hard line that is on the car now. That new hard line should connect to the existing rubber hose (which is then connected to the chassis-mounted hard lines and the master cylinder respectively).

 

Thanks thats what i need to hear

 

Exactly!

 

its that posible guys or not just swap the calipers and lines and keep the small rotors?