Stock brakes with S52?

[iXBeater]

My search-fu apparently sucks - I'm sure there's a thread somewhere, but searching "Brake", "Upgrade" and S52" and others didn't find a thread. Apologies for what I'm sure is a covered-topic.

The Question: How well do the stock brakes work in an S52-swapped E30? What are solid upgrades?

The background: I bought an E30 with the S52 swap, but don't have it yet. One of the few things on the car that isn't upgraded are brakes. This will be a daily but may see a lap or three so I'm wondering what a solid-but-not-crazy upgrade is. The car has the 944 booster.

Thanks for any thoughts/help/links!

[82eye]

stock will work no problems. there's any number of upgrade rotors and pads for easy bolt on. beyond that there's hundreds off bbk's for the e30, near every vendor has one. most will require larger wheels etc.




edit : there's also the m3 set up.

[iXBeater]

stock will work no problems. there's any number of upgrade rotors and pads for easy bolt on. beyond that there's hundreds off bbk's for the e30, near every vendor has one. most will require larger wheels etc.




edit : there's also the m3 set up.

Definitely not going M3 swap, at least any time soon. This car is already highly modified, has great wheels, and was a bit of a snap-purchase, so I'm going to try to be judicious in how much I bite off with it (i.e. a bolt-on to what's already there is much-preferred).

The car has 15" wheels, so I'd guess the Wildwood 15" kit would be fine. I can't say I hate the idea of something that pretty. Mainly I don't want to hack something together.

I guess I'm going to drive the car a bit and let it tell me what it wants ;)

[Panici]

You won't need big brakes unless you're pushing for laptimes.
The stock set has no trouble hauling the car down from the end of the speedometer a few times in a row (with a decent set of pads).
My brakes have enough power to get into lock up even when feeding into them progressively. Obviously this will depend on the tires and booster you run.


Planning a track shakedown with my car in the springtime. Probably making 300whp now with boost turned all the way down.
I expect to get at least 5 laps before they start fading. YMMV.


Personally, I would explore cooling/ducting first before a BBK.

[mtech325]

For daily driving the stock e30 brakes work perfectly fine even with an s52 swap. As for the track, recently I had the chance to go to Thunderhill East which has a couple back to back 100+ mph straights and the stock brakes with PFC08 pads and Motul brake fluid held up fine throughout several 20-30 minute sessions during the day. Since I didn't know what to expect with the stock brakes on track with the swap car, I also installed Bimmerworld's brake duct backing plates and ran the silicone ducting from the valence openings. As time goes on I may want bigger brakes or 5 lug wheel choices, but for now my car is still a street car so the current setup works fine to go out and have fun.

[iXBeater]

Many thanks for the insights!

[hoveringuy]

stock brakes are fine, upgraded pads and fluid will even get you around the track fine. What you'll run into is that the rotors just won't last long under hard use and will crack like crazy. You'll be going through a lot of rotors.

[amcp]

I went through the same situation with my s52 e30. I drive the car mostly on track and wknd. At first I used the stock setup with a 944 booster. On track with pfc pads and cooling to the front the car did ok. Pedal feel was a bit flaccid and while I didn't have issues, it didn't inspire confidence. I bucked up the pennies for the 15" wilwoods race kits. The brakes can handle anything I can throw at them.

[digger]

IMO the brake pedal on stock e30 is terrible, sure you can lock the brakes but its harder to modulate and slower to reach maximum retardation and just not confidene inspriing, maybe best described as a bit like a laggy non resposive turbo but in reverse. You can run better pads but thats pretty shit for a daily driver as there are always compromises with horrible squealing and grinding noises that evenually rear their head, chewing rotors, corrosiove dust that says hold my beer to OE dusty pads making you spend more time cleaning wheels than driving, to sub optimal retardation when the brakes are ambient.

The e90booster swap and M/C is what i would do, the brakes will be more reponsive / firmer and better assist to make up for it and it doesnt screw the bias. A modest OEM BBK is also what i would do on a street car with a big chunk more power than stock over something from wilwood that way you can use an OEM jurid/textar compound which are simply the best pad for a daily driver as all the street pads for those aftermarket calipers are nowhere near as good for a daily.

i went from stock (multiple compounds) to
280mm wilwood dynapro front (tried about 5 compounds) stock rear now to
312/294 OE ATE basically e36 m3 caliper fr and rr and e90 booster
First time in 20years owning the car have the brakes worked likey should and suits the additional power levels

its a totally different story for the track so wont comment much on this other than to say a race engine and street engine are different things and building an engine that does both compromises things so build it for what you do most

[TobyB]

(with a decent set of pads).

This.
And ducting, but only for the track.

Also, if you're cracking/checking rotors, switch manufacturers. Brembo used to be AWFUL for this, whereas
the Balos never had a problem. Now it's all CDM, I would just try different versions if you have a problem. Centric 'premium' were pretty good, a while back.

As to feel, I agree with Digger- and I too blame it mostly on the way the booster works. It doesn't react quickly at stock ratios.
I found a bit of improvement with a 318 master and rear bias valve, but a booster with a valve that requires more pedal pressure
and releases faster would help a lot. For street use, brakes are quite different than track brakes, though, and a lot of
what's 'good' is subjective. So try it, and then in your shoes, I'd start with different boosters that were easy to swap.
Nothing worse than doing a lot of custom work to fit a Ferrari 455 booster, only to find it sucks worse than stock.

t