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Posts posted by Paula&Marcus

  1. Hi All,

    I know of some V8 that have snapped the 5th gear of, but I donot know one single 4-Cylinder that actually did the same ... even the highest modified ones donot break 5th gear ...

    Is there anybody who knows a 4-Cylinder who has broken the 5th gear ???

    IMHO, its the low down torque that weakens the primary shaft 5th gear overhang over time ... and its only the V8 that can deliver that much torque low down ... additionally the V8 has a longer 5th gear than the 4-cylinder Esprits what makes the whole thing even more problematic ...

    IMHO, all 4-cylinder owners are pretty much safe here ...



  2. Hi Olaf,

    Here is my personal advice for the 4-Cylinder ...

    - best place for the injector is the MAT-thread

    - relocate the MAT-sensor into the square plenum (where the boost gauge hose connector used to be)

    - place the rerservoir above the pump ! (if you like you may use the windshield washer reservoir ! This is very clever and already has a low level light !)

    - NEVER place the reservoir obove (= higher) than the injector !!!!! This is VERY important, because the water may run via graviatation by itself into the engine !!! You can imagine what will happen when you want to start the engine -> hydraulic lock ... huchhhhhhhhhh



    Who has such system installed. Gathered information?

    Where is the best place to induce the water/alc.mix ?

    I am just curious


  3. Sky,

    Are you 100% sure that you did not mix up the inlet/outlet ports of the c/cooler pump. I remember one scenario that was very sililar and it turned out that the port have been mixed up (swapped) by mistake.

    The port at the bottom should feed the c/cooler and the port at the top of the pump draws coolant from the radiator and is also connected (T-ed) with the small reservoir.

    If both connections are swapped by mistake you will pressurize the small reservoir and you may loose coolant through the overflow pipe. The pressure will rise with rpm ... you see the pattern ?

    Result is missing coolant and very low efficiency of the whole system (= faily hot c/cooler).


  4. Hi All, Hi Bibs,

    JFYI the impellor is produced by a company that usually produces PU and rubber components for the food industry, but its not a standard of the shelf part at all.

    It is produced custom made only for the Esprit application. There have been drawings and prototypes before and it was also made sure that it holds up in very hot coolant environment.


  5. Hi All,

    I personally feel quite uncomfortable about what was going on in the end of this topic "Electric Chargecooler Pump vs uprated impellor":

    1. IMHO the CEO (Bibs) of a forum like this should not be too biased, I think its essential for this position to be as neutral and tolerant as possible ...

    2. Simply closing a thread like he did after posting his own words is pure dictation IMHO !

    I feel nobody should use the given power in a wrong and biased way ...

    Sorry Bibs, but I feel that you have done something here that was not right.


    PS: I hope you are not simply deleting this topic now, or moving it somewhere where nobody will find it, please dont misuse the power you have.

  6. I asked two official Lotus dealers here and they did not confirm that !

    They told me that they strictly stick to Blue (Castrol) antifreeze, because there is no written advise in the workshop manual updates that recommends OAT for the Esprit.

    They also share the same point of view that OAT may make trouble if put in older cars ... they also told me (I didnt know that) that OAT was introduced not because its better, its just not that bad for the health and the environment. Looks the same like the R12 -> R134 thing ... R134 also is not better ... actually its worse.

    BTW, can you remember the water pump trouble VW cars had when they put in OAT ?

    Because of that they had to switch from plastic pumps back to aluminium pumps again ... that was back in the 90th.

    In the end its a philosophy ... everybody has its own.


    If you call Lotus now and ask what coolant they recommend for my 1989 Esprit, they will say OAT. If you ask what gearbox oil, they will say TAF-X.
  7. Hi All, Hi Bibs,

    We have discussed this OAT-eats-impellor-thing with the manufacturer yesterday. He told us that it probably will be possible to make it OAT resistant ... but what comes next ?

    In the end we have decided that we will not change the impellors, because we and the manufacturer cannot tell for sure if this works with all OATs and all future upcoming formulas ...

    We know that it is perfectly resistant against good blue Castrol Antifreeze and that is also what is recommended by Lotus.

    I would like to add your own words here Bibs (you wrote that in the gearbox oil thread):

    "Castrol TAF-X is ideal, it does the job and works perfectly, there is no need to choose another lubricant"

    Just swap the TAF-X with Antifreeze and the word lubricant with coolant.



  8. Charlie,

    Sorry to say that ... but I bet that you snapped your main-shaft-5th-gear-overhang.

    Its quite a typical failure ... may happen.

    Usually it happens on the Autobahn at high speed when you lift the throttle to 0% and then put your foot down again to 100% within 1-3 seconds.

    Its easy to verify. Just remove the rear gearbox covver and have a look.

    You will see that 5th gear came lose (= the shaft snapped and the gear is still attached to the fragment).

    Time to remove the gearbox and rebuild it.


  9. Arent the rollers/dynos just another substitude for real life .... :blink:

    ... jokes aside ... the Esprit actually is one of those cars that "donot like" rollers/dynos. If you do it, please do in wintertime and choose one with a HUGE cooling fan.

    Otherwise you will simulate something that has nothing to do with real life on the road ...



  10. Jonathan,

    This is very strange, because in closed loop the A/F will stay strictly to lambda 1 (= 14,7) and this is a quite lean mixture that is not suited for higher power and higher boost.

    All the 4-cylinder ECM equipped cars (MY 88+) and also the V8 leave closed loop when on full TPS/boost ... thats why people get the well known fairly rich mixtures (down to A/F 10:1) when they do dyno runs.

    Hmmmmmm ...



  11. Hi Jonathan, Hi All,

    Yes, you are right. With #3 and higher the soleniod is vented 100% at low rpm to get quickest possible spool up times. This is common practice and if you look at the factory S300-tables its done there the very same way from factory. I dont think doing this is wrong ... if it would not be like this, I'm sure people would complain and point out that our chips are not programmed properly.

    IMHO, a good turbo will not have any problems there.

    Yes, c/cooling is always a very important factor. The cooler, the better, especially on hot days.

    Of course, MAT will rise at high boost and with sustained high boost (whenever you can do that more than a couple seconds !) it will rise to a stationary level, in theory. This depends mainly on ambient temp, boost level, turbo-efficiency and c/cooler efficiency ... But, I'm sure you will not be able to experience this stationary level ... maybe on an air-field or a salt-lake its possible.

    But, you are right, the better the c/cooler efficiency, the better the overall performance, of course.



  12. Hi All,

    As soon I have a feedback from the manufacturer if it is possible to make it OAT resistant I will inform you.

    BTW Bibs, we had the prototype impellors tested extensively before we had the first batch made ... no we did not use apple juice as a testing-medium ... :( We tested with recommended Castrol antifreeze (actually it was old coolant) and never saw any problem.

    I personally would stay away from OAT in Esprits (not only because of that impellor). The Esprits cooling system was designed decades ago and IIRC blue Castrol antifreeze (and similar) was recommended by Lotus. From my experience the blue antifreeze works perfectly and there definitely is no need to use something different - why changing a running system ?

    IMHO, its also very important to change the coolant and flush the whole system at least every two years. Not because the coolant itself gets old but you have a horrible material mix in that cooling system and getting things neutral and clean in there is always a good idea.


    It's not a massive surprise that an impeller from a food blender isn't compatible with anti-freeze. Will you be contacting people who have purchased this item from you and removing it from sale Marcus, what are you plans?
  13. Hi All,

    Two days ago we handed over Bib's "red" destroyed impellor to the manufacturer. We also informed him that the coolant used was the red/pink one with OAT-technology.

    Today we got the info that it was actually the red OAT coolant that softened the PU-material and also dyed the whole polymer red.

    Now he is checking, if he can modify the PU that it will be also resistant against OAT in the future.

    I will tell you what comes out ... very soon.



    PS: All others who use the yellow PU impellors with non OAT coolants (= blue, green, whatever) please dont worry ... the PU will not get attacked.

  14. Hi All,

    Please have a look at your plumbing ! For a good efficiency its essential that the pump sucks from the lower radiator outlet (the one at the bottom) and then pumps into to front (in driving direction) c/cooler inlet.

    If you mix up the pump connections (= flow direction will get reversed) you will end up with lower efficiency and also with a disturbed header tank function, because the pump pressurises the header tank ... no good idea.



  15. Hi Alex, Hi All,

    We carry these impellors for a few years now and there have been 3 batches so far ... The impellors get custom made for us and each batch has around 40 pieces. There have been sold about 100 of these impellors so far.

    All impellors we had the opportunity to check after some time (the last one we could check was Stefan Ertler's after quite a long time; you know the one with the Sport 500 project) came out flawless.

    But, there was no car I know of, that had the red (organic acid) coolant in it ... maybe it has something to do with it ... or not ... who knows.

    Honestly I have never seen one that has failed till I saw the pics from Bibs and heard the words from GKP.

    I hope we will get an explanation from the manufacturer once he has the chance to examine one of the two that have failed.


  16. Hi All,

    IMHO you received a lot of wrong information.

    The mechanical boost is set to 0.35 bar (~ 5 psi) thats the level, you will get when the ECU is doing NOTHING !

    Everything above 0.35 bar is controlled/added via ECU. And its done in a quite complicated way upon a lot of parametres and sensor inputs. If everything is 100% you will get these max boost levels with your standard ECU (its gear dependent !):


    Maximum is 0,75 bar.

    Of course, if the ECU is seeing some odd sensor input, then it will reduce max. boost. If one or more values are very "bad" then it will reduce max. boost down to 0.35 bar. (Less than 0.35 bar is not possible, because this is a mechanical thing)



  17. Hi All,

    Jokes aside ... today I showed Bibs pictures to the manufacturer of the PU-impellors.

    BTW, its a manfufacturer who mainly does impellors for pumps used in the food industry.

    He told me that he would like to examine the destroyed one and additionally he offered a free replacement for everybody who has experienced a failure within 3 years.

    Bibs, could you please send me the old destroyed impellor ?!

    Many Thanks


    PS: Does anybody know how many of the PU-impellors have failed so far ... is it 2 ?

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