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Has anyone had experience with these brake pads? I was reading an advert recently they say that they are softer than the OEM pads and are idea for uprating the brakes of cars with no servo. (Or I guess for cars with a wimpy servo like the Sportster).
They aren't cheap so I would like to find out a little more before I splash the cash....
hi, i use green stuff on my Lexus is200, it brakes well on saves me loads of time not having to clean my chrome wheels every 5 minutes, the claim 70% less dust adhesion, i would say they are pretty close with there statement.
I would avoid EBC I've heard nothing but bad things about their products on other forums I frequent. Obviously this is second hand info as I've never tried them myself
The thing I regularly see mentioned about EBC - "Every Body Crashes"
That said, I had some red-stuff pads on the Jag, and I never crashed...
Hmm - I wonder if the problem is that everyone who fits the EBC pads expect a miracle cure for thier brake problem - and of course that doesn't happen. I don't see how they could keep selling them if they don't do the job - sooner or later someone would sue. (They sell them in America too - so probably sooner).
Mind you at £50 it is an expensive experiment if they don't do the job. I will think on...
Boost ratio is only 1.9:1. Mind you if you used that AND the Metro servo that would give you (where's my calculator) 3.04:1 - still not great compared to the BM's 6:1.
not great but quite a bit more. Thing is I can still lock the wheels even at speed it just requires a lot of commitment on the pedal. It would be nice if they were a tad more sensitive.
Hi all, I have been thinking about the brakes issue.There is a solution to budget big brakes by using front calipers from a mazda rx7 with adaptor -plate and using corrado discs.With regard to the servo, what about using a universal '7 inch dual diaphragm brake booster'--have just googled that and there are chromed servos for 60-70 quid.
Boost ratio is only 1.9:1. Mind you if you used that AND the Metro servo that would give you (where's my calculator) 3.04:1 - still not great compared to the BM's 6:1.
Robin
Rob
I have investigated this a bit, and am left wondering if a servo offers a constant boost, not a multiplier of foot pressure. The boost comes from the negative pressure generated by the vacuum of the inlet manifold over the surface area of the diaphram. Therefore the maximum boost is a constant (for a given vacuum): I assume the amount of that maximum boost available is controlled by the distance travelled by the push rod, otherwise the moment the brake pedal is touched the full boost will be applied?
If this is true, then the boost from a servo is directly proportional to the square of its radius. (surface area =pye x r squared). And if it has a dual diaphram then it will offer twice the boost of a single.
By this calculation a dual 7" has the same surface area as a 10" single.
Out of interest, what size is the standard BMW servo, or the Sierra servo?
Out of interest, what size is the standard BMW servo, or the Sierra servo?
A Sierra one is 8" (assuming the measurement isn't across the full width of the unit including the seam joining the two halves, but 8.5" if it is). The unit in an M50-engined E36 appears to be 10" (a bit awkward to measure it in situ though).
A Sierra one is 8" (assuming the measurement isn't across the full width of the unit including the seam joining the two halves, but 8.5" if it is). The unit in an M50-engined E36 appears to be 10" (a bit awkward to measure it in situ though).
Thanks for that. I reckon the Metro is only 6.25" at most.
Assuming that servo boost is relative to surface area of the diaphram then using the 10" BMW as a base the relative boosts are:
Metro - @6.25" = 39%
Sierra - @8" = 64%
Dual - @2x7" = 98%
BMW - @10" = 100%
If the above is an accurate reflection of the boost available it helps explain why the Metro servoed brakes require significant foot pressure to make them work. Does anyone have a different take on it?
I am now very interested in following up the Dual 7" as I think it could be made to fit, with a little care and ingenuity.
I hadn't noticed before that you're tight for space for a servo, but it's clear enough to see there. My Cabrio's like, for example, Simon's in that my servo's mounted directly on the bulkhead i.e. not on a protrusion as on yours. That means the available width on mine isn't reduced by the bonnet and the Sierra servo fits without any problem. My bonnet detail's also different - the lower section is narrower than yours as it's just a tight fold over of the aluminium sheet (my upper and lower bonnet sections are hinged together). Must get some photos online somewhere...
Mike wrote:
Does anyone have a different take on it?
I've never considered how a servo works but it does seem reasonable to conclude that the assistive force isn't multiplying the force applied through the pedal but is instead simply adding to it (and usually greatly exceeding it?). Whether or not a dual diaphragm 7" unit gives 98% of the force of a single diaphragm 10" unit presumably depends on the same pressure difference existing across both diaphragms? I suppose that's quite possible but it must make the innards quite complex.
Might you end up with too much assistance from a dual 7" unit though?
I hadn't noticed before that you're tight for space for a servo, but it's clear enough to see there. My Cabrio's like, for example, Simon's in that my servo's mounted directly on the bulkhead i.e. not on a protrusion as on yours. That means the available width on mine isn't reduced by the bonnet and the Sierra servo fits without any problem.
Hi Mashtun
How do you find your brakes with the standard Sierra servo?
Do you have drum or disc rear brakes?
I am aware that fitting a 200BHP engine means that if I want to use its performance I need brakes to match, and have been concerned from the outset about pedal pressure: particularly as I am now used to modern "over servoed" German performance.
I have fitted the larger Cosworth/Granada discs at the front, and have the Sierra discs at the rear, so I'm happy that the caliper capacity will be sufficient, but guess with the little Metro servo the pedal pressure is likely to be high? Patrick and Robin's comments about their brakes seem to support this.
There is of course more to it than just the servo boost - the bore of the master cylinder, and the mechanical advantage of the pedal arrangement are factors too.
Could I end up with too much boost? - I certainly felt my first Audi was over boosted - it took me ages to brake lightly they were so sensitive, but after 7-8 years I have become very accustomed to them.
I am still very tempted to explore this option, but others' views would be welcome.
Modern cars have very light brake pedal so I don't see 'too light' being a massive issue as you kinda get used to it.
I suppose you just need to be very careful of locking up the wheel without ABS and needing to let of a bit again in an emergency stop situation.
Both good comments.
Us older folk (anyone learning pre ABS) were taught to cadence break in an emergency, so I may have to revert back to it, instead of relying on the ABS !
