Why Are Modern Car Brakes So Sharp?

[Super Josh 4]

IIRC right hand drive 205 GTIs use a smaller servo than LHD 205 GTIs so maybe the LHDs are more like modern cars?

 

Why is that then Kieran? Is it due to a lack of space. Does that mean we can't upgrade to a larger servo then?

 

 

 

Josh

[jackherer 543]

I assume its due to lack of space but thinking about it, with a standard 8v engine does the servo run close to anything other than the fuel filter? (which could easily be relocated)

 

With an Mi16 the cyl head/cam cover would prevent fitting a larger servo I would have thought.

[Super Josh 4]

With an Mi16 the cyl head/cam cover would prevent fitting a larger servo I would have thought.

 

Isn't it just the MC that gets in the way of the Mi lump though? Won't the extra servo diameter just be against the bulkhead?

 

 

 

Josh

[GLPoomobile 958]

Isn't it just the MC that gets in the way of the Mi lump though? Won't the extra servo diameter just be against the bulkhead?

Josh

 

 

But if you think about it, if the servo diameter is greater, that puts it's centre further down the bulkhead, and in turn the MC will sit lower down, so more likely to interfere with the Mi camcover.

[Tom Fenton 1,541]

Surely the centreline of the servo is dictated by the pedalbox and the poisition of the fulcrum on the brake pedal. Therefore going to a larger diameter servo would theoretically leave the master cylinder where it is.

[jackherer 543]

Are the 'bigger' servos larger diameter or deeper? For some reason I thought it was the latter...

[tom_m 0]

Are the 'bigger' servos larger diameter or deeper? For some reason I thought it was the latter...

 

doesn't answer your question but for what its worth the smaller servos are certainly the same depth and a smaller diameter

[Super Josh 4]

But if you think about it, if the servo diameter is greater, that puts it's centre further down the bulkhead, and in turn the MC will sit lower down, so more likely to interfere with the Mi camcover.

 

But if you think about it Steve, the MC is in the centre of a circle. Therefore it doesn't matter how big that circle is the centre will always be in the same place. That's what I think anyway.

I wonder which cars have a bigger servo that would fit onthe 205 pedal box? 405, 406? time to get out the tape measure.

 

 

 

Josh

[GLPoomobile 958]

Surely the centreline of the servo is dictated by the pedalbox and the poisition of the fulcrum on the brake pedal. Therefore going to a larger diameter servo would theoretically leave the master cylinder where it is.

 

Yes, you (and Josh) are correct. As per usual my logic is arse about face - I was thinking along the lines that the OE servo is stuffed under the bulkhead lip, so a bigger diameter servo would have to move down to fit (moving the centre point down) and completely overlooked the obvious fact that it would require a lot of re-engineering due to the peddle box.

 

You can tell I'm not an engineer, eh? Bloody tit LOL!

[de Noir 0]

 

Left slimmer 255mm servo from 405, right 225mm 205 OE servo...

Former fits on pedal bracket but doesn't fit under the hood - bulkhead lip above it and chasis side structure are too close.

[jackherer 543]

I thought the LHD 205 GTI Servo was 229mm?

 

RHD 205s have a 178mm servo the same as non-GTIs.

[tom_m 0]

RHD 205s have a 178mm servo the same as non-GTIs.

 

no they don't, RHD gti's still have the 225mm servo, i've just swapped mine for the smaller one off a base model. HUGE difference in diameter. parts cd confirms this too

[Anthony 1,003]

Why would you possibly want more servo assistance than a standard GTi servo anyway? I can't think of much worse than turning what are good, reasonably feelsome brakes into the hateful over-servo'd ones with no feel or feedback that modern cars have, but each to their own...

[jackherer 543]

no they don't, RHD gti's still have the 225mm servo, i've just swapped mine for the smaller one off a base model. HUGE difference in diameter. parts cd confirms this too

 

I got those figures from a haynes manual.

[de Noir 0]

225mm diameter is from Peugeot spare parts. It's diameter of the servo drum, outer lip adds further 5mm, making it approx 235mm in total. 225mm unit is deeper than larger 255mm unit.

 

Why would you possibly want more servo assistance than a standard GTi servo anyway? I can't think of much worse than turning what are good, reasonably feelsome brakes into the hateful over-servo'd ones with no feel or feedback that modern cars have, but each to their own...

 

I thought larger servo would blend nicely with 23,8mm mc and 54 or 57mm front calipers... Upgrade all around...

Edited January 11, 2008 by MH_

[tom_m 0]

I thought larger servo would blend nicely with 23,8mm mc and 54 or 57mm front calipers... Upgrade all around...

 

only if you enjoy bouncing your head off the steering wheel a lot

[de Noir 0]

He he... Yeah!

[cybernck 402 1 Cars]

no need for that, stay with standard M/C if you want light and responsive pedal (but with long travel like on new cars)

or fit the appropriate 23.8 mm M/C if you want to retain standard pedal feel. or in your case, 22.2 mm M/C .

[de Noir 0]

No need for two engines in a 205 either, Nick.

Edited January 15, 2008 by MH_