QUESTION
I am starting to use my Elan +2 for real and I took it for a rather long tour in the Alps last week.
No complaint about the Dual Master Cylinder sourced from your company, but I am not too happy with the brake boosters.
The (originally UK) car was modified to dual brake circuit with dual Master Cylinder and two Lockheed boosters (one for the front brakes and one for the rear brakes) to satisfy Swiss Authorities.
Because the guy who did import it had only the single Girling booster that was fitted originally he fitted two new Lockheed units.
When I brake progressively, the braking starts slow (no assist) and then beyond a certain point the servo kicks in.
It does provoke an uncomfortable braking surge.
When I let the brake pedal go, during a second or so the brakes lightly stick before they fully release.
Not too satisfying either.
Tonight I tried the no-servo mode. I did not change the brake fluid piping.
I just disconnected the vacuum hoses and plugged the one connected to the carburettor manifold. I must say that although I did not try it for long, I was rather happy with the result:
Braking force proportional to the pedal pressure, no surge, no sticking and I was able to lock the rear wheels when braking with decent force (the rear wheels lock 1st, maybe I should work on the front/rear balance)
However, I was surprised and uncomfortable when reading your warning:
SAFETY WARNING - This master cylinder is not a substitute for removing the Girling remote servo on a vehicle that is going to be used on public roads"
Does this warning also apply to me running a dual brake circuit?
Why do you discourage people from using your dual M/C and no servo?
F.W. - Switzerland
ANSWER
If you are going to use your Elan +2 on public roads then its wise to have your vehicle in an operational condition as specified by the Lotus Factory
Modifying the brake system in any form has legal implications and hence the safety warning
I have written more about this subject on the Lotus Marques web site but here is a summary-
SNIP.........................
There is an ill-founded recommendation to remove the standard Girling brake booster and to change the brake master bore size to obtain "a better brake pedal feel".
This often results in brake master cylinders being replaced without due consideration given to an increase in wear when changing bore diameter .
The remote brake booster significantly reduces brake pedal effort and is a safety critical component as it reduces stopping distances.
Removing the brake booster is an inappropriate idea as it will extend the vehicle braking distance and has the potential to invalidate any insurance claim in the event of an accident.
Why would anyone want to disadvantage themselves whilst driving in traffic when modern vehicles are equipped with stepped bore brake master cylinders that result in shorter breaking distances?
The removal of the brake booster will the increase the brake pedal force, accelerate wear on the pivot spindle, pedal, clevis yoke, clevis pin and push-rod plus results in excessive flexing of the fibreglass firewall.
SNIP.........................
From your description it would appear you have a servo problem which should be rectified as quickly as possible.
It should be noted carefully the Elan +2 was originally produced in two forms - see the Lotus parts manual.
Domestic specification where it was fitted with a single line brake master cylinder and one servo.
Federal (export specification) where it was fitted with a dual master cylinder and two servos.
Today modern day vehicles are fitted with dual/split brake system to provide an improved level of safety
I would encourage you to repair the faulty servo so you have a safe vehicle to drive.
If you are unsure about the legality and safe operation of Lotus Elan +2 when removing the brake booster, then please seek advice from your local Road Authorities.
Copyright © 2019 Lotus Marques
I am starting to use my Elan +2 for real and I took it for a rather long tour in the Alps last week.
No complaint about the Dual Master Cylinder sourced from your company, but I am not too happy with the brake boosters.
The (originally UK) car was modified to dual brake circuit with dual Master Cylinder and two Lockheed boosters (one for the front brakes and one for the rear brakes) to satisfy Swiss Authorities.
Because the guy who did import it had only the single Girling booster that was fitted originally he fitted two new Lockheed units.
When I brake progressively, the braking starts slow (no assist) and then beyond a certain point the servo kicks in.
It does provoke an uncomfortable braking surge.
When I let the brake pedal go, during a second or so the brakes lightly stick before they fully release.
Not too satisfying either.
Tonight I tried the no-servo mode. I did not change the brake fluid piping.
I just disconnected the vacuum hoses and plugged the one connected to the carburettor manifold. I must say that although I did not try it for long, I was rather happy with the result:
Braking force proportional to the pedal pressure, no surge, no sticking and I was able to lock the rear wheels when braking with decent force (the rear wheels lock 1st, maybe I should work on the front/rear balance)
However, I was surprised and uncomfortable when reading your warning:
SAFETY WARNING - This master cylinder is not a substitute for removing the Girling remote servo on a vehicle that is going to be used on public roads"
Does this warning also apply to me running a dual brake circuit?
Why do you discourage people from using your dual M/C and no servo?
F.W. - Switzerland
ANSWER
If you are going to use your Elan +2 on public roads then its wise to have your vehicle in an operational condition as specified by the Lotus Factory
Modifying the brake system in any form has legal implications and hence the safety warning
I have written more about this subject on the Lotus Marques web site but here is a summary-
SNIP.........................
There is an ill-founded recommendation to remove the standard Girling brake booster and to change the brake master bore size to obtain "a better brake pedal feel".
This often results in brake master cylinders being replaced without due consideration given to an increase in wear when changing bore diameter .
The remote brake booster significantly reduces brake pedal effort and is a safety critical component as it reduces stopping distances.
Removing the brake booster is an inappropriate idea as it will extend the vehicle braking distance and has the potential to invalidate any insurance claim in the event of an accident.
Why would anyone want to disadvantage themselves whilst driving in traffic when modern vehicles are equipped with stepped bore brake master cylinders that result in shorter breaking distances?
The removal of the brake booster will the increase the brake pedal force, accelerate wear on the pivot spindle, pedal, clevis yoke, clevis pin and push-rod plus results in excessive flexing of the fibreglass firewall.
SNIP.........................
From your description it would appear you have a servo problem which should be rectified as quickly as possible.
It should be noted carefully the Elan +2 was originally produced in two forms - see the Lotus parts manual.
Domestic specification where it was fitted with a single line brake master cylinder and one servo.
Federal (export specification) where it was fitted with a dual master cylinder and two servos.
Today modern day vehicles are fitted with dual/split brake system to provide an improved level of safety
I would encourage you to repair the faulty servo so you have a safe vehicle to drive.
If you are unsure about the legality and safe operation of Lotus Elan +2 when removing the brake booster, then please seek advice from your local Road Authorities.
Copyright © 2019 Lotus Marques