Does a S14 brake booster fit a S13?

[DamnedButDetermined]

I need to replace mine and have found someone willing to sell theirs from an S14.

-DbD-

[AKADriver]

yes.

ABS and non-ABS aren't compatible, though, so make sure you get the right part.

[sykikchimp]

weird.. I thought the only difference was that there were a couple extra holes that you could plug up?

[AKADriver]

Well, yeah.

ABS master cylinders have one less open port. Non-ABS have three ports (left front, right front, both rear). ABS have two (both front, both rear).

[andrave]

really?
i thought the abs one had 3 also, because the s13 abs used both rears on the same "channel"???

[AKADriver]

Well, exactly. The S13/S14 ABS system is three-channel.

The ABS-equpped cars' master cylinder has two ports; one for front, one for rear. The ABS unit splits the fluid flow for the front internally and does the two front channels. It treats the rear fluid flow as one channel.

The non-ABS cars' master cylinder does the split for the front wheels itself, so it has three ports.

ch' ch' check it out:
http://mywebpages.comcast.net/akadriver1/images/brakes.gif

This is basically straight out of my 1990 FSM.

[andrave]

I did not realize that, thank you for clearing that up.
I'm very confused now.
I was at a junkyard in florida and came across a 240 with a different arrangement than mine had (mine is non abs) and I assumed it was ABS, it had I believe 3 outputs, but it was obviously a lot different than mine is.
do dohc cars and sohc use different master cylinders?

[AKADriver]

DOHC and SOHC use the same m/c.

[sykikchimp]

So the ABS-NC has only 2 ports? or does it have 3 ports, and one is closed from the factory?

I seem to remember seeing a 300zx ABS MC that came from the factory with one plugged port, and 2 open... I assumed that they used the same MC to save in production caosts?

[AKADriver]

Hmmm... yeah, that might be true.

The hard part is getting that fitting for the plugged port. IIRC people ended up having to destroy their old M/C to get the fitting out.

[d240t2]

But isn't the original question about brake boosters, not MCs?

For boosters...the vacuum port is on opposite sides. Other than that, it is interchangeable, as far as I know. You'd need to redo the vacuum hose to reach, or get the S14 hose to match the booster. Seems easier to just swap the right one.

As for MCs, it is silly to swap S14/S13 MCs. Internally, they are roughly the same (neither is an upgrade for the other), but the line placement is completely different. You'd waste at least half an hour rebending the lines, when you should have just gotten the right MC, or done an upgrade that warrants bending of the lines).

Dennis