E30 325i Cabrio - improving brake performance

[rdjohn]

I have owned this car from new and used to eat through pads and disks at a regular rate.

On Tuesday, I was taking it to my garage for the suspension to be replaced after winter layover. I was driving at 60mph towards the local Range Rover dealership who had parked display cars along the nearside kerb. A Jaguar saloon, pulled out so that he could see past the parked cars and was perfectly placed so that I could T-bone him in the driver’s door. I stood on the brakes and not much happened, hydraulics pushed pistons, but no ABS rattle, just gentle retardation.

I thought that I was about to get seriously hurt, but guessing that I had probably slowed to about 30mph, managed to swerve round him without clipping the corner.

My garage has now replaced the discs and pads and says that now they are ‘not bad”. I am not reassured, I would prefer that they are perfect. As I am sure that with either of my other cars, I could have stopped in a straight line.

I think the original hydraulics are ATE, I think I can get an ABS master cylinder, but not callipers.

Has anyone done, or able to recommend, any sensible upgrades without going to a track spec? The car is normally driven sedately with the top down, but I have to have a car that can do an emergency stop, when needed.

Thanks for your thoughts

[rdjohn]

Hi, thanks for the information

Whenever I have done brake reseals (a very long time ago), it was always the piston corrosion that was the biggest issue. Biggred have the seals, but no pistons, Brakes Int. have pistons and seals from Budweg, who I have not heard of.

You have me wondering about the flexible hoses being the real problem when I stood on the pedal. Hopefully, I will get the car back tomorrow, and gently run-in the new pads and then have a big rethink.

I do not want to sell the car after so long, but then I never want to relive/die the experience that I had last Tuesday.

[rdjohn]

InitialDave said:

Hmm, that certainly doesn't sound right, the stock brakes in good condition should haul you up just fine.

I assume you want to keep the car as-is with a 4 bolt hub, yes?
And does it have 14"/15" standard wheels or aftermarket larger ones?

That's going to set the restrictions you're operating within for upgrades.

I want to keep the car original, after so long. As you say in 1990, the brakes worked fine and it was driven much harder then.

I am looking to get the brake performance as close to original as possible.

[rdjohn]

williamp said:

Are they bad, or normal (brakes have improved massivly over the years). All mot testing stations have brake testing equipment. I'd be tempted to get in on the rollers and ask them to test the brakes. Youd know if they are all bad, or just ome axle..

From new they easily triggered ABS if I stood on the brakes. For the first 10-years, I frequently warped the front discs.

On Tuesday, my first reaction was that I had sufficient distance to stop. I merely slowed down a bit.

[rdjohn]

Budweg are Danish. I did not know that they had an automotive industry.

[rdjohn]

I will get the car back on Tuesday and a bit of bedding in time, before I go to France at the end of the month. Unfortunately I cannot devote much time as moving house at the moment.

Brakes int. show calipers as out of stock. If I go down that route I will check if they can get them.

Perhaps the brake lines only swell when you stand on the pedal. Just a thought.

[rdjohn]

I suppose a problem is it only does perhaps 5-6k miles every year, so servicing is pretty ad hoc. Tending towards - need to do.

So the answer is I have no idea, maybe never! A good example is the cam belt. Every 50k, or 5-years. Cant remember exactly when it was last done, but I am pretty sure it was before 2019. That was also done last week.

The brake fluid has now been replaced, but I usually ask for that to be done fairly frequently. When I fired up this year, most of the clutch fluid had gone. But just topped it up and it is OK. that has now been flushed.

Perhaps I need to keep a check on what has been done, and when.

[rdjohn]

Thanks to everyone for your kind help.

There has to be a good solution in there.

I have thought for some time that the pedal travels too far. It feels solid before the engine is fired up but the servo seems to make it feel soft.

As someone mentioned, brakes on modern cars seem so much better.

[rdjohn]

It has been on the rollers this morning. The Fronts locked, as expected. The Rears did nothing so new discs and pads are on the way.

I have asked him to check the hoses.

He thinks the hydraulics are OK, probably means no visible leaks

[rdjohn]

I got the car back yesterday. The pedal feels a whole lot better. Initial retardation is good, but I have not yet been on a road sufficiently quiet to trigger the ABS.

I suspect all will be OK, before replacing all the hydraulic elements.

Thanks to everyone for your help but esspeciallyThe Conflated Outlier for his contribution

[rdjohn]

Just returned from a fortnight touring France.

The brakes are sufficient for the MoT, but do not inspire confidence. I think the hydraulics still need looking at as I cannot trigger the ABS with heavy pressure. Perhaps with other things that have been found it could be a vacuum / servo issue.

A number of other problems arose while over there. I took it to a Youngtimer garage that I used to use while living over there as the tick-over became erratic. They did not have the time to do, but diagnosed that it needs,

New tick-over valve
New inlet manifold to MF unit hose
New thermostat housing and thermostat
New hydro coupling for the fan.

Doe anyone know a classic BMW specialist in NW England? Most of the recommends here are for newer Mini and BMW specialists. Knowing where / how to obtain reliable parts is the hard bit, putting them on is relatively straightforward.

Thanks again, if anyone has good suggestions

[rdjohn]

JakeT said:

Darren Wood are good and in Stockport, they should have little issue sorting out those jobs on your car. Annoying the ABS still can’t be triggered.

Thanks, I had spotted his webpage, which struck me as a more modern car specialist. I will give him a call.

[rdjohn]

d_a_n1979 said:

You'll find most parts you need on the likes of Autodoc etc; using RealOEM for part numbers

If you need genuine BMW parts; try the various BMW dealer sellers on eBay UK (ie. Douglas Park, Listers BMW etc) plus BMWs own eBay page and speak to the guys at Cotswolds BMW also who offer forum discounts

Where are you in the North West so folk can give recommendations for mechanics?

I live in Wilmslow

Autodoc seems to come up on every search that I make, but then they are always “currently out of stock”

Last time I visited the local dealership, we had most of the mechanics around the car saying “we never get to work on cars like this”

The official BMW seems only to have 4-parts for my car. It is easier to get stuff from Germany.

The car is only 34-years old, but no one seems really interested, The real money is in new cars