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Posts posted by MrDangerUS

  1. On 05/07/2012 at 11:41, giorgio67 said:

    Hi guys,

    thanks for your words.

    No, sadly for what I know the calipers of the Lancias are different and also more expensive!


    Hey, Giorgio,

    I read this thread again and I want to complement you on your effort and documentation.

    How is your gear box working (now)?

    Are you still driving your Esprit or sold it?


  2. I also had a low pressure reading at the tick over on my S4S (32K miles). When hot, it was in the red zone.

    Front glass (plastic) on 3 original Caerbont  gauges separated /caved in.  PO tried to repair by gluing them, but they failed again.  Use of cyanoacrylate fogged my water gauge.

    Got p.. off and have replaced all with metal can VDO gauges and senders w/real glass. Original parts were made of plastic and failed miserably.

    In addition, my new turbocharger does not require full oil flow. Triple ball bearings CHRA has an oil restrictor (0.4mm hole) raising oil pressure in the whole system v. effectively. Tick over pressure never been below 20psi hot.







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  3. On 08/11/2022 at 16:56, Elite 4.9 said:

    Actually there are other ways of eliminating dry bearings at start up and that is by using the proper oil and additives. 

    I use Royal Purple synthetic oil in all my rigs both old and new as synthetic oils are far superior to old petroleum base oils on all fronts. This oil clings to surfaces and prevents any damage or at least minimizes them to a great degree. It also produces a measurable amount of added hp even to other good synthetic oils.

    I also use, in all my engines including lawn mowers and small engines, Lucas oil treatment. It is an additive that is a heavy oil and basically does the same thing as Royal Purple.

    Most people think RP is too expensive but we are talking about your engine here and you can make it last longer than almost any part of your car if you desire. Cheap insurance IMHO.

    I learned about Lucas oil treatment from a friend who drives a big rig semi and he told me most all truckers, that he knows, buy this by the gallon. He bought a semi with a Detroit diesel engine, 14 liters, that uses many gallons of oil in its sump so buying synthetic simply wasn't an option as it was just too much money put out to change the oil.

    But he took this truck with 700,000 miles on it ( never rebuilt ) to a million miles and even achieved as much as 8.7 mpg ( his best ).

    This stuff works and can be added to any engine oil so you can rest in knowing you can protect your engine bearings from wear at startup. It also will give you a little more oil pressure giving better power and mileage especially in a car with more miles on it. It will also stop your smoking engine almost totally from excessive ring wear.

    Funny story, another friend who also swears by it, had an older, small Chevy pickup, with many miles on it.  He put 100 % Lucas oil treatment in because a rod started to knock...but he still needed to drive it to work. It stopped the noise and continued to run without noise, believe it or not. 



    I have learned about Lucas Oil Treatment "honey" in the 80-s. Fantastic product, it sticks and coats parts even if you leave the car sitting for a long time.

    Esprit S4/ S4s has an interesting feature: with engine not running, when you depress accelerator pedal to the floor you  can crank the engine as long as you want without starting it. In this pedal position, the ignition and injectors are disabled. This feature is advertised as a method to "clear" your flooded engine.

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  4. On 23/11/2022 at 00:04, Sam Grant said:

    John D - is that running on a different tune/map or the stock s4s tune/ecu? What is the price on the "stock looking" but not stock turbo? :) 

    @Sam Grant  No need to re-map, unless you're tracking the car.Turbo delivers stunning performance with OE S4s MK V chip and 370 cc/mm RC Engineering "peak and hold" primary injectors and 270 cc/min (25.7 lb/hr) RC Racing high impedance secondary injectors, (the same as Dermot's, ).

    please gimme a shout at for further details

  5. Nothing exotic, on the budget, but quite effective!

    On my S4s, I've kept stock frt springs ( 234#) and shocks, but replaced ARB with 17mm dia rod off S350, and increased rear spring rate to 275# (Eibach # 1200.300.0275 S ) with LOTAC 05405 shocks .

    Car handles fabulously, no roll in corners, rides like "on rails"! I like it very much. 

    Above changes were NOT expensive, yet very effective!


    • Like 1
  6. FYI:

    Have installed the thicker 17mm ARB and poly bushings on my S4s.

    S350' ARB, PN# A082C4254F, 17mm dia  is available from SJ SportCars UK, high quality repro part. Easy installation.

    OMG, what a difference in handling! Enjoying ride like "on rails" very much.
    No leaning in corners and did not experience any noticeable oversteer. image.gif.4d2e8b4f5eb9f3299a53cc00bd223961.gifimage.gif.e80bedc592b3f117981c2dd3689d3498.gifimage.gif.c5af02cb60100601b4bbda5b6c6fe6c9.gif

    Note: my rr springs were upgraded from 256 to 275 lb/in. Both mods are working together quite well.

    Is 96 V8  245lb/in front and 274ln/in rear?




  7. On 09/12/2020 at 16:11, plumdeplakmuis said:

    V8 makes 400Nm so I guess the GT3 should be able to cope with it. 

    GT3 gear box is NOT the same as later V8! I would suggest an upgrade!

    All the UN1 Lotus Gearboxes are very similar. This is the 'simplified' history.

    These changes included Revised Gearchange & Synchro on Reverse Gear. The introduction of the Esprit GT3 created another variant of the UN1 gearbox. This variant is only approved for the 2 Litre version of the Lotus Turbocharged engine. This version of the UN1 is designated UN1 – 028 and has a different Crownwheel & Pinion that is only suitable for use and validated for the GT3 engine. UN1- 028 is not recommended for use on the 2.2 Litre Engine.

    UN1 – 016 – 4 Cylinder G/Box – First variant of Lotus UN1– First used on X180 Introduction in 1988. This 'Box had rear cover with L/H shift lever.

    UN1 – 026 – High Torque G/Box – Stronger Casings etc. introduced circa 1993. This 'Box had rear cover with R/H shift lever

    UN1 – 027 – V8 Gearbox – Introduced in 1996 on V8 Esprit. This box was basically similar to 4 Cyl High Torque units with new Clutch
    Housing. It carried over the R/H shift lever. It had synchro on Reverse Gear and a higher 5th gear. The shift mechanism was changed to an improved version of the R/H mechanism from VIN W2272 – this requires a different shift master unit and cables.

    UN1 – 028 – 4 cylinder G/Box for the Esprit GT3 (2.0 Litre) w/different Axle &Gear Ratios - not suitable for 2.2 Litre Engine Torque.

    In a nutshell the 026 & 027 Gearboxes are very similar except for the Clutch Housing, Synchro on Reverse, 5th Gear Ratio. The clutch Housings & Rear Cover (with shift lever) can be changed over easily. Minor improvements were introduced at the time of Sport 350 to improve durability.

    The Lotus versions of the Box were very similar to Renault units at first sight. What people do not realize is that the Lotus versions had some very important differences. The main issue is the crown wheel & pinion. Although the Ratio is identical to some Renault vehicle applications the material is different. The Renault material will not survive the Lotus application (even the earliest non intercooled cars). Running on the approved oil is another critical item.

    Basic History of UN1 Gearbox

    UN1-016 -- Original Esprit application -- 315 Nm (232 lb-ft)

    1988, DOM/ROW intro, 1989 Fed Intro, left side shift translator

    UN1-026 -- Esprit Hi-Tork -- 400 Nm (295 lb-ft)

    1993, intro, stronger case, right side shift translator

    UN1-027 -- Esprit V8 -- 400 Nm (295 lb-ft)

    1996, V8 bell housing, higher 5th ratio, synchro reverse.

    1998 , a modified cross shaft for direct cable shifter .

    Minor durability improvements with Sport 350 intro.

    UN1-028 -- Esprit GT3 -- 300 Nm (220 lb-ft) WEAK!

    1998, like 027 but with lower third & final drive ratios (1.41 & 4.11 ??).

    CWP ratio not suitable for torque of the 910 or V8 (GT3 = 2.0 liters).

  8. Finally, I have replaced the "dryer" air inlet hose with 3" aluminum tube and silicone elbows/couplers.       My upgraded flow turbo spools much faster, now.  Expected/estimated 20% flow improvement.  Car feels much more responsive.

    All parts are from the eBay.  Parts used:

    -30 deg bend 3" dia tube, cut to suit

    -75deg bend 3" dia tube, cut to suit

    -3" to 2.25" (2.5"?) straight reducer from CAI tube to turbo inlet mouth

    - 3" to 3.25" ( measure your air box outlet dia) to 3" tube, straight silicone reducer for air box to CAI tube transition.  And, misc. worm clamps

    IMO, rear trunk floor has to be removed to fit/clamp everything easily, unless... you are a magician.







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