What's the real deal with E32 master cylinders?

[ELVA164]

Alright.

I've read various things about this and can't come to any clear understanding whether or not doing this is worth it.

4/87 325i.

I have a stock braking system and a spongy pedal.

I've bled everything more than once, and I've changed soft hose, pads, etc.

Solid rotors, ATE pads.

Pedal does not sink with the car on or off, though it does get stiffer after one pump in both situations.

I'm aware the 25mm cylinder is not internally biased, and will increase rear bias. I'm not aware if that makes any real difference under normal street driving.

I have ABS, so I'm not worried about the number of ports. I believe the pipes/hoses on the car will pop right in, but please let me know if that's not the case.

My goal would be to get rid of some of the sponginess and pedal travel. It would make heel-toe a little nicer and would increase my comfort using the brakes a bit.

1) Does this make a noticeable difference re: pedal travel and feel?
2) Is the increase in pedal pressure annoying for regular driving?
3) Anything else I'm not aware of?

Thanks!

[ELVA164]

Brake master cylinder update:

The master cylinder size in my car is 20.64mm front and rear with an external proportioning valve. A late-model cylinder is
22.20/17.64mm, obviously internally proportioned.
If I go to a late-model cylinder, I'll actually make my brake bias worse unless I remove the bias valve on the car and install a new pipe.

If I go to an E32 cylinder the bias stays correct but the change in size is considerable. I'm wondering if it would be too much.

Do I:

A) Use a late-model cylinder and remove the valve; or

B) Use the E32 cylinder?

[IRON-E]

Well, I just purchased a Willwood BBK for the e30, so I have some similar questions.
I also purchased a brand new e32 master with hopes of improving my braking all together.

[ELVA164]

I would imagine the change in pedal travel/stiffness in your situation would not be as significant due to the amount of fluid at each corner, but that's just conjecture.

[IRON-E]

I would imagine the change in pedal travel/stiffness in your situation would not be as significant due to the amount of fluid at each corner, but that's just conjecture.

Thanks man, have yoh installed yours ywt?

[ELVA164]

I've decided to get a factory late-model master to replace my early one. I think 25mm is way too big a jump from 20, especially for a car with stock brakes. Haven't done it yet because I've been swamped prepping the Datsun for the race this coming weekend.

[IRON-E]

I should be tackling these 2 jobs, within the next couple of weeks. I'll report back with any findings. I can't post pics off my phone, so I might just use words to the best of my ability.

[ELVA164]

Words?! What is this, the 80s? :D

[wworm]

in for updates. Very curious about this.

[IRON-E]

Words?! What is this, the 80s? :D

Word.

[ELVA164]

UPDATE

I got the late stock E30 master installed and the pedal feels much better. If you have a pre- 5/87 build date car and don't like your pedal, but you're keeping stock brakes, just use the late stock master.

[wworm]

UPDATE

I got the late stock E30 master installed and the pedal feels much better. If you have a pre- 5/87 build date car and don't like your pedal, but you're keeping stock brakes, just use the late stock master.

whats the difference between early and late masters?

[AndrewBird]

whats the difference between early and late masters?

The master cylinder size in my car is 20.64mm front and rear with an external proportioning valve. A late-model cylinder is
22.20/17.64mm, obviously internally proportioned.

;)

[IRON-E]

I love/hate this place.. lol, anyway I'm not sure everyone has seen this thread yet but...........

https://www.r3vlimited.com/board/showthread.php?p=4898133#post4898133

I'm now on the hunt for an e92 brake booster and I'm gonna mock everything up, do some measuring to see if the e32 master will work with this booster for my 24v swap and complete a write up.

[digger]

late model e30 MC is 22mm front and 17mm rear?