A&Q about Lotus
Q:
Hi,
I have test driven 2 Elises recently in a different garages.
On both cars I had to break a little early in order to stop.
The breaks did'nt seem very responsive.
Does the Elise use ABS?
A:
Strange - brakes are excellent in Elise but do require some force
111S doesn't have ABS - 111R has ABS
A:
111S doent have abs. Have you driven a car without abs before?
111R'brakes on the other hand feels like normal car, just better.
A:
Both cars I drove were 111S and I noticed I had to push a little harder than normal on the peddle.
I have never drove a 111R.
The fact that the breaks on the 111R are ABS, would this mean that pressing the break would result in quiker stop / more responsiveness i.e. no force needed like on the 111S
I also drive a van and found that the breaks are more responsive that the breaks on the 111S.
A:
Originally Posted by clive_gargan
Both cars I drove were 111S and I noticed I had to push a little harder than normal on the peddle.
I have never drove a 111R.
The fact that the breaks on the 111R are ABS, would this mean that pressing the break would result in quiker stop / more responsiveness i.e. no force needed like on the 111S
I also drive a van and found that the breaks are more responsive that the breaks on the 111S.
What you mean is that they are easier to use (not much force required) and you are just not used to non-abs brakes.
Non-abs brakes, if anything, are quicker in response since they use less components, but unless your a super being, you wouldnt notice any sort of delay at all. Thay are also easier to modulate and hnt is a lot easier and more natural.
There is definately no difference in effectivness or peformance (unless you lock them up). Just a little more force required to push the pedal.
A:
The difference in force required can be due to one of or a combination of many factors. Most of the factors can be eliminated if we assume the system is clean and working as designed, leaving cylinder size ratios, valving, moment arm of pedals, vaccuum assist levels, etc., as variables in the amount of force required that are actually design issues instead of fault issues.
Although most modern passenger cars are designed to have a force curve within a certain range that we are all accustomed to from having driven a number of different production cars, it would be a bad assumption to think that all braking systems feel the same.
If you leave everything else the same but have a shorter moment arm on the brake pedal, it would require more force. If you leave everything else the same but have a master cylinder bore slightly larger in relation to the caliper piston bore area, it would require more force.
A braking system set up as described above will require more pedal force, but less pedal throw. It will be equally effective, but might not feel as responsive if you're not used to the firmer pedal feel.
Now that I've said all that... I don't know anything about the 111S system! HA! Was just rambling to hear myself talk, I guess.
xtn
A:
I don't think that Clive is really talking about ABS,but power brakes which he may be used to in an everyday car.Power brakes need very little pressure to get good stopping power,whereas un-boosted brakes would give him the feeling of having to stop sooner using the same brake pedal force.JMO
A:
Originally Posted by peck555
I don't think that Clive is really talking about ABS,but power brakes which he may be used to in an everyday car.Power brakes need very little pressure to get good stopping power,whereas un-boosted brakes would give him the feeling of having to stop sooner using the same brake pedal force.JMO
Exactly what I meant.
A:
My understanding is the 111s does NOT have power brakes, therefore the harder push required.
A:
Yes!
The 111S has non-assisted brakes, which are great!
Once you get used to them you will curse and shout at any assisted brake setup (sorry to say, including the 111R!) for taking away a lot (or in case of cars like VW/Audi's, ALL) of the feel and feedback in the brakes.
Also love the way how the brake pedal has very little travel in it. You just apply more pressure to the pedal, but unlike assited brakes, the pedal moves relatively little.
Bye, Arno.
A:
Originally Posted by Arno
Yes!
The 111S has non-assisted brakes, which are great!
Once you get used to them you will curse and shout at any assisted brake setup (sorry to say, including the 111R!) for taking away a lot (or in case of cars like VW/Audi's, ALL) of the feel and feedback in the brakes.
Also love the way how the brake pedal has very little travel in it. You just apply more pressure to the pedal, but unlike assited brakes, the pedal moves relatively little.
Bye, Arno.
+1 id trade my brakes for ones in S
A:
So, what happens if you disconnect the servo in our 111R braking system or replace it with a manual master cylinder?
Do we gain the non-assisted feel?
What are the dangers of this?
A:
You'd need to remove the brake servo, replace the master cylinder with the non-assisted version and remove or bypass the ABS hydraulic unit.
Then you'd be back to the original Elise brake setup.
But if you do this then I'd personally put in a dual MC setup with a balance-bar to regulate the front-rear brake bias in one go.
Disconnecting the servo does not give good results as the master cylinder is of a different diameter and not meant to be operated by 'foot pressure' alone, so it will feel very dead and you need to press very hard to stop.
Oh.. The above procedure is probably possible on '05 cars as the extruded alu pedals should still have the same/similar pickup point for the master cylinder pushrod as the non-assisted cars.
On the '06 cars with the copy of the VX220/Speedster pedal box you probably need to change the brake pedal too to bring the connection to the push rod in the same place relative to the pedal pivot point.
Bye, Arno.
A:
Arno,
Do you buy any of the arguments about power-assisted braking being necessary as the weight of the 111R / Exige has grown so much since previous versions? Or was this simply a decision to get ABS in?
- Justin
A:
Originally Posted by Arno
You'd need to remove the brake servo, replace the master cylinder with the non-assisted version and remove or bypass the ABS hydraulic unit.
Then you'd be back to the original Elise brake setup.
But if you do this then I'd personally put in a dual MC setup with a balance-bar to regulate the front-rear brake bias in one go.
Disconnecting the servo does not give good results as the master cylinder is of a different diameter and not meant to be operated by 'foot pressure' alone, so it will feel very dead and you need to press very hard to stop.
Oh.. The above procedure is probably possible on '05 cars as the extruded alu pedals should still have the same/similar pickup point for the master cylinder pushrod as the non-assisted cars.
On the '06 cars with the copy of the VX220/Speedster pedal box you probably need to change the brake pedal too to bring the connection to the push rod in the same place relative to the pedal pivot point.
Bye, Arno.
Thanks Arno! I think of Stan as our American Arno.....almost.
When are you coming to the States to run with us?
A:
Originally Posted by Vantage
Or was this simply a decision to get ABS in?
Spot on..
Although ABS without vacuum brake-assist is technically possible, it's in the area of motorsport parts and quite expensive and in many parts of the world probably not certified for road use.
Since ABS has become a requirement for type-approved cars in Europe Lotus had to do something.
A 'traditional' setup with vacuum assist, normal ABS hydraulic unit and Lotus designed software in the ABS unit was their most economical solution.
As they could ummm.. 'borrow' the setup from the GM/Vauxhall VX220/Opel Speedster (it always had ABS) the choice was pretty simple for them.
Lotus did re-do the software side of the ABS system completely though, as the GM software could be pretty lethal on the road (extreme 'ice mode' on any small road imperfection...). The current 111R software is actually pretty darn good for such a low cost system.
Bye, Arno.