Calling All Brake Gurus

[G_Reaper]

Hi Bibs

I was making reference to where the bean counters at Lotus decide to spend the money not at the expertise skill etc... of the engineers as they can only do what they are told to do with the given funds. I feel that if this problem had ocured on a newer model or especially a model still under their warranty they would have sorted it by now. This problem is keeping owners/enthusiasts cars off the road not to mention the safety aspect

Any news on how the test is going?

Cheers Mike

Sorted................MR2 master and Servo.Hi Spec front calipers, disabled ABS, now I have brakes that really work.

Pics as promised,

That's great Martin!!!

Can I pop down and have a look at your system, I only live NR. Chester-le-Street.

Cheers Mike

PM me with a contact number please I cannot seem to PM you.

Edited December 28, 2010 by G_Reaper2

[MartinL]

Hi Mike, welcome anytime, give me a call on 01325 374309

[MartinL]

Update..........................

Now have Subaru Impretza 1" master and servo fitted, solved the pedal travel issues and stronger mountings to stop the "spongeeeeeee" pedal

So much nicer to drive when you have confidence in stopping power

Just about ready for that Nurburg trip............ (Shhhhhhhh, dont tell Anne)

[RV_ABZ]

They're testing it Mike on an S4s they've had at the factory for some time.

Would you believe that the clever and experienced engineers working on solutions for decades old cars don't get involved in opening shops!

Hi Bibs, any update on that point?

[G_Reaper]

Hmmm???

How long to test a pressure switch?

[Bibs]

This long and then a little bit more.

They're just testing the production ready version.

[RV_ABZ]

Haaa, so there is light at the end of the tunnel!

I wish they'd be ready before en of April; I'm supposed to take the Esprit for a couple of rounds on a circuit. Nice & gentle for a 1st time, but it'd be nice to have "normal" brakes. I'm still on my workaround solution.

Edited March 10, 2011 by RV_ABZ

[G_Reaper]

Yeah its great!!! But you can bet after all this time the light is a HUGE pound sign.

I am still going to go down the route of ditching the master cylinder etc as the brake feel was poor and inconsistent when it was working. It also means that when anything else fails associated with this system I am not waiting 18 mths + for a solution.

Cheers Mike

[RV_ABZ]

I inquired towards Lotus Esprit Australia about the presure switch back last November. Got this reply a few days ago...

"We have located the switch which is made to order from an overseas supplier.

The estimate price is the same as what Lotus use to sell it for $850 dollars.

If you are still interested please let me know.

Regards

Tony Papas

MB: 0418 547 709"

I think I'll pass at that price!

[Kenekster]

Hello all :-)

I recently acquired an S4 1994 car, I've been reading various posts on here about the brakes. I hope someone can help me with some information.

My ABS light was on flashing initially but then constantly. I decided to remove wheel ABS sensors to inspect/ clean them, managed one front out, the other broke. Now a rear has also broken as was seazed solid , have to drill out the remnants, anyway !!

Does anyone know of the part numbers for these ? I rang PNM who wanted 42 pounds for one, seems excessive :-(

Other thing I have noticed is the brake pedal, under braking seems to push back against my foot. Is this normal ? Also went out for a drive the other day, a little scary :-( under heavy braking on approach to a corner, pedal suddenly went well down and brakes didn't work very well, eek !! oh sh**** I thought at time. Now not confident of driving it fast and then expecting it to stop before hitting something solid.

I hope someone can help ?? Oh ye ABS light now out on having broken 2nd wheel sensor, thanks for any guidance given

Ken

[rogerch]

I inquired towards Lotus Esprit Australia about the presure switch back last November. Got this reply a few days ago...

"We have located the switch which is made to order from an overseas supplier.

The estimate price is the same as what Lotus use to sell it for $850 dollars.

If you are still interested please let me know.

Regards

Tony Papas

MB: 0418 547 709"

I think I'll pass at that price!

PM Ramjet in WA, he's got the go on this stuff.

[G_Reaper]

Hi

I am about to put a full set of wheel sensors on ebay. Starting price £70.

I had the same problem with my my brakes on my S4s. I drove Martins S4 with the master cylinder and servo off a Subaru Impretza WOW!

So I have ditched the Lotus ABS system and fitted the master cylinder and servo from the earlier Stevens cars. I worked out that if a simple item like a pressure switch is obsolete for the Delco ABS system it stands to reason everything else is obsolete, or if you use the rule of supply and demand used by Doug V Breakers "its obsolete so we charge as much as we can and you can bloody well like it! If you can buy a Lotus you can bloody afford to pay stupid prices as well"

I thought it better to get rid of a generally poor brake & ABS system for standard non ABS with more bite and feedback.

Note : Lotus take forever to find replacement parts still no replacement pressure switch for the ABS system after at least 18mths!!!! You can bet you will need to re mortgage to be able to afford to buy it when / if it isever available.

I am currently working with Martin to perfect the Vacuum supply to the servo watch this space. If you want more info PM me.

Cheers Mike

Edited April 14, 2011 by G_Reaper2

[MartinL]

Lets face it, S4 brakes are crap, 15 + years back they may have been up to the job but time has taken its toll on the Americanised system Lotus fitted using solenoids and electric pumps making the whole thing more complex than it needed, Lotus soon realised this and reverted to a vacuum servo and master cylinder for the GT3 and V8 and parts for this set up are now almost unavailable or impossible to find via Lotus.

Lotus have no intention of continuing to supply parts for older models so it makes sense to find alternatives that work, only the purist and the concours geeks need stick with total originality and thats ok cos they probably dont drive that hard but if you want to use the car as it was intended then to me a braking system that works is important. As mike says I am using a Subaru master and servo (a MR2 is a simpler fitting job) with a Audi vacuum tank and vacuum direct from the engine, this is simple and it works well. We have experimented with vacuum pumps but are currently trying to source suitable vacuum switches but I am unsure as to gaining any great benefit from this,......................watch this space

Best of luck to you guys wanting to wait for pressure switches, as I think you may find you end up spending a fortune and still have no consistent braking, watch out for that 40 ton truck in front, he can stop, can you????

[Kenekster]

Hi G Reaper,

Are the wheel sensors suitable for my 1994 S4 ? Are they new or 2nd hand ? Regards and thanks

Ken

[G_Reaper]

Hi Ken

Yes they are the same as an S4. They are used but immaculate. I bought them when I was having trouble with my brakes but discovered the fault was else where so never fitted them. The car they were removed from had only13000miles on the clock.

Regards Mike

[DanR]

I don't know what's out there but some diesel alternators run a vacuum pump opposite the pulley. Could be worth exploring as it offers an elegant solution.

[CarlC]

I took a trip over to Martins to check out his setup and Martin also kindly took me out for a spin to see and feel them in action. Martin has done an excellent job putting this solution together. The whole replacement setup is a fraction of the cost of even a re-con of the existing system. This really is a no brainer. The delco brake system is dead. If you replace your pressure switch it will be the internal seals that will go and the system gives a dead feel even when it does work.

I've got my bits ordered and will be ripping out the old system this weekend.

I won't be spending hundreds of pounds on a new pressure switch only to get my crap brakes working again. Instead, I'll spend a whole lot less and have some really good brakes that start to match the performance of the car.

I do have to say it's excellent of lotus to be looking into this but the pressure switch is just part of the problem not the solution.

I'll be doing what I can to assist Martin as I should end up with the identical setup by the end of the month. Im also confident that there is plenty of improvement to be made in this system Martin has setup. This should give us excellent braking capabilities by the end of it .

Thanks for your time last week Martin. It really restored my faith in just how great these cars can be!

Edited April 14, 2011 by CarlC

[G_Reaper]

It would be if there was room, the Esprit alternator is not large in size but it virtually touches my intake plenum o the S4s. The system Martin and myself are trying to develop involves using natural intake vacuum

from the engine and Vacuum reservoir + running an electric vacuum pump switched by an electric vacuum switch. This system would offer triple redundancy i.e your engine cuts out the electric pump cuts in if the pump fails you still have engine vacuum, if both fail you have a reservoir of vacuum to stop your car and your normal manual braking without the servo assistance is also there. That's better than the original system by some margin. As soon as it is perfected we will let you know.

Driving Martin's car and seeing how simple his conversion was convinced me this was the route to take. THANKS Martin.

Cheers Mike

[lotus4s]

It would be great if one of you guys would do a "how to" with pics and such.

[Kenekster]

Hi Mike,

With reference to the S4 ABS sensors, can you give me your telephone number as I would like to discuss those with a view to purchase. Thanks,

email kenekster@gmail.com

Ken

[G_Reaper]

Does anyone know the min and max vacuum most brake servos work at of the top of there heads?

Regards Mike

[mr.oogieboogie]

hello martin you in box is full, i too have a an s4 with poor brakes so in info on parts to get , parts to remove will be great

[MartinL]

For all that want to see/try my brakes, you are welcome...............

I should be at Gaydon for supercar Sunday if you dont want to have a trip North!!!!!!!!

martin

HOW MANY s4 ESPRITS IN ENGLAND ????

HOW MANY HAVE CRAP BRAKES ???

[G_Reaper]

Hi

OK I have a supplier who can do the pressure switch for the ABS system. I need the operating on and off settings in Bar. I also need the screw thread type. My supplier manufactures for the motor industry the switches would be pre set with the required values from the factory. I also need to know how many people would require one.

I also need to know if the switch contacts are normally in the open or closed position.

If someone can help with the technical specs I can have the switches within 2 weeks. The price will NOT be hundreds of pounds either!!!

Cheers Mike

Edited April 18, 2011 by G_Reaper2

[sanj]

I have available a used pump and switch assembly from a '91 SE with fewer than 7200 miles on the odometer. Contact me if interested...