Single Piston to Four Piston Calipers
 

I have bought the OEM four piston calipers, brake pads, and stainless steel brake lines from corksport for the four piston conversion already.

I have 5 lug wheels on my 1990 FC. The rotors have the same part number at the parts store for four piston and one piston so I believe this is all I will need for the conversion after eyeballing and bolting on the calipers.

Just wondering if anyone has done this and experienced any problems or needed additional parts before I start taking the brake lines off.

nope. no problems. they are going to go right the fuck on. easy as PIE.

the 4 pots are half hard line and half soft line. youll figure it out. either way, its easy. too simple.

I have searched and saw that someone suggested a bigger brake booster as well- Is this really necessary?

i did the swap on a 91 coupe.

the front rotor/hub/spindle is the same. all you need to do is remove the old caliper and bracket and replace with the new caliper.

pads are different

the only other thing, is the 4 piston calipers have a short little hard line. if you have the hard line, then its like a stock t2.

if you don't then, you need to make or buy them.

no. you can use the whole soft line from the old calipers.

nope, the s5 t2 has a bigger booster, but all of the other 4 piston cars don't

It's N/A and I have the steel braided lines I bought should I just be able to mate those together.

If you're on a budget, no.
The pedal travel will be longer but the brakes will work fine.

I doubt you'll be able to tell much difference, street driving- to more fully exploit the larger calipers a bigger booster/MC is necessary.
A popular conversion is the setup from a 929 ( 1" MC bore), I run a Subaru 1 1/16" bore setup...both of which are almost direct bolt-in swaps (minor brake line tweaking/fab required).

I did not use the stainless steel portion because it was impossible to separate the brake line in the middle to implement them from the hard line to the line that leads to the caliper. My front brakes need new pads so I just went ahead and attempted to put the four piston calipers on without the stainless steel upgrade because I was going to save that for another day.

Well I ended up with two four piston calipers with stripped threads trying to put the brake line into the caliper. I was very careful and did this outside of the car on a bench to make sure it did not go in crooked but the threads still stripped on the inside of the caliper. I am guessing this means I will need the specific line for the four piston calipers to use them because the threading is different.

Sir Cygnus- Have you done this brake swap before? You say I can use the same line but it ends up stripped, any advice?