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drdoom

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  1. Chris, Regarding the brake sizing, never forget that Lotus were on a scant shoestring budget for years while the Esprit design program was underway. I have no doubt that certain pieces chosen for production were less than optimal, instead chosen by virtue of cost requirements. Back in the day auto journalists would refer to "Chapman, the Alchemist", or make suggestions in terms of handling black magic. Typical bollocks all that, and ACBC would have had a chuckle I'm sure at the vacuous remarks. The laws of physics have always dominated the matter of motorcar dynamics immutably, and Lotus distinguished themselves in grasping the pertinent details eminently. That is to state the obvious. In terms of bits, however, I challenge anyone to explain why 205/70 rear tires were fitted other than as a cost mitigation. Look at the bloody scale of the rear wheelwell for a clue, if the fore-aft weight distribution doesn't already make clear that larger rubber was intended. On the question of brakes it must similarly be that the components came to be chosen due to supplier dictates taking precedent over design parameters to some degree. Note that Lotus, at first opportunity to further pursue development of the car, scaled up the rear tire versus front and the front rotors versus rear. In your case I suggest you enjoy the journey of discovery which awaits. Try out your new front brake set-up in threshold braking exercises in the dry and in the wet and see what has been accomplished. By my modest capacity for analysis I figure the Esprit brake bias for dry should optimize components somewhere in the realm of 62/38 fore-aft. We should also bear in mind how the differing tire diameters affect the actual braking torque applied at the point of contact with pavement. Keep us posted! Cheers
  2. Hi Fabian, All very nicely done! So the screen tape is applied to the windscreen exterior? I just assumed it would be on the inside so not suffering wear. Cheers
  3. Those are some ghastly results of tinkering with the masterful work of GG and the ACBC team, absent a measure of sense of what was achieved in the first place. Want Ferrari taillights buy a Ferrari. Want a Lola T70 buy one. There's plenty of fertile soil to till when it comes to tidying up the trim aesthetics on early Esprit's but I've yet to see any major mod improve the beauty of the car in the least. That's a most charitable statement, by the way. Ferkin travesties is more on the nose.
  4. The American firm, Wilwood, lists quite the variety of pads with detailed information as to the operating characteristics. One should be able to cross reference their parts with pads of others' manufacture. Cheers
  5. Hello Jacques, It appears that your wheel pictures did not load. Cheers
  6. That's a lovely result Fabian, thanks for the great tutorial! Is there no trim across the top of the screen? Cheers
  7. By the way, for Lotus Manual specs to be correct regarding the front spring rates, the Federal springs must be made of thicker wire. They are effectively longer, 10.5 coils versus 9 for Dom/Euro, so must either be of thicker wire or otherwise would be of a softer rate. No getting around that. Still, Lotus information has not always been ironclad, anti-roll bars for example. Over on the V-8 Esprit forum there has been discussion of a-r bars found fitted which did not agree with the Factory specs. When I pulled apart a 1964 Elan for restoration it most certainly had a 5/8 a-r bar from factory yet you will find no reference to such a thing in any literature on the cars. All references are to 11/16 bars.
  8. Lez, where one is to commence the count of free coils from the bottom end is the point at which the wire has ramped into upward incline, separated from the perch, bench or floor as the case may be. Your count of 11 or 12 equates to 10.5 if you take another look at your posted pictures, in light of this. Cheers
  9. The flattened coils are not to be counted as the kinematics don't task them as they do the free coils, as I have read. Just got off the pot and took a look here and there for something helpful to add, so offer the following: from the S1/S2 Lotus Shop Manual front coils Federal are 10.5 coils, 34.6 cm overall length and 63.63kg/cm rate ( 140 lb/in for us old-timers ), Dom/Euro are 9 coils, 35.3 cm length and 55.14 kg/cm rate ( 121 lb/in ). Coil diameter for both is 10.0 cm. Also, I checked what my S2, 78/07/100S, was fitted with at Factory and, lo and behold, the front coils would have numbered 9 before I cut 1 free coil off. I will attach pictures of my untouched car at rest, plus a shot of prepped springs for reference. Note that my car was fitted with A/C at Factory, sold into Canada originally yet not fitted as Federal. Interesting.
  10. I'm no expert on anything but I do try my best to acquire sound knowledge. Geert, Giniw and I are all concurring in these considerations, I'd say. Lez, little doubt you will find that the coil diameter of your springs matches that of Geert's. The seats at both top and bottom perches are sized accordingly and, additionally, there's practically no chance any alternative street spec springs were ever produced in numbers for the Esprit. That said, my pal who'd cut a bit off the OEM set to happy effect had first tried a set produced to his spec by a reputable local firm. It was when these non-OEM springs sagged badly that he resorted to the shortened originals. Can't speak for what went wrong with the custom set as they were produced by the same firm I very successfully had produce uprated springs for my classic Elan. If your springs don't serve as desired I cannot see why it would be amiss to cut something off in order to shorten and firm up. It's not as if they are irreplaceable, and I'd venture you have no plans to rallycross the car. I'd take perhaps 3/4 coil off using a metal cut-off wheel on a high speed angle grinder, appropriate safety gear for hands and face/eyes. That is what my S2 will ride out on when the restoration is wrapped up. Wheel rate derives from the simple spring rate by way of the suspension motion ratio. To illustrate motion ratio, picture how when the tire/wheel move up or down a given distance relative to the chassis the bottom spring perch moves in step but to a lesser degree, as the distance from lower arm pivot (bush) centerline to perch C/L is less than the distance pivot - wheel C/L. More technical than is needed for our purposes as hack engineers.
  11. Geert's got it right, the more the coils all else remaining equal the softer will be the spring. The compressing of a coil spring primarily results in a torsion force on the free coils, far less a bending force. So if one pictures a coil spring to be a compactly arranged torsion bar it is perhaps easier to see why the greater number of free coils would be softer. To compare these 2 sets of springs, Lez, you'll need to determine the wire diameter and work through the above formula for a start. To accurately anticipate the change of ride height through a change of spring you'll also need to measure and calculate the wheel rate. On the other hand, the photos make clear that there is no flattening or grinding flat of the top coil, so Giniw's remarks critical of cutting a part coil don't seem applicable in this application. Cutting something off the free end coil will result in a measure of rate increase, an increase in stress of the spring wire itself, and something of a reduced ride height. It's unclear to me that your car sits unduly high at the front, taking what one can from the photos. There are ground clearance specs for the Esprit in the factory manuals, by the way. Cheers
  12. Hello All, For the benefit of those who wish to rebuild Dellortos, or for that matter other sidedraught carbs like the venerable DCOEs, I suggest one check in at the Sidedraft Central forum hosted on Yahoo by Keith Franck. KF is a very meticulous researcher/developer who has been diligently testing such carbs for well over a decade and has in the course of this created components offering distinct improvements. His most recent are alternative emulsion tubes, which are receiving accolades. As well as the components, which are available at his webstore, there is a great wealth of information available via the forum. There is much to be had in terms of understanding proper set-up of these carbs and not all the conventional wisdom has held up under scrutiny. FWIW Sidedraft Central - Yahoo Groups.url Webstore Online Auctions for Member DCOE_Tuner.url
  13. Lez, To pick up on George's points, do be mindful of the possibility that the gearchange linkage may have been previously adjusted to cope with the trans displacement withered mounts might well have wrought. So in restoring things with a healthy set of mounts it seems possible that the linkage was consequently put out of sorts, therefore in need of adjustment. Cheers
  14. There is a brand, Pertronix or something similar, which offers Lucas distributors with a programmable advance curve by way of an onboard module. Something to consider in maintaining original appearance whilst making use of some very handy technology. Cheers
  15. I do know that the exhaust side leg is indeed shorter than is the intake side. The reach to chassis is obviously shorter on the X side owing to the motor leaning over onto that side. Your situation is interesting, Pete, as it puts the focus squarely on the broader aspects concerning early series' engine mount performance. To recap, the early powertrain locating is done very simply by way of the legs/biscuits (legs/bushes on the earliest) up front and the transaxle hangers from which the aft end dangles, with a minor role played by the trailing arm mounts. That's it. Next point to consider: what movement is to be expected as the forces are applied. The first set would be the result of engine rotation, no load as at idle or otherwise out of gear. That would be the set of vibrations innate to an inline 4 banger, roughly termed as shaking/rocking in 2 planes 1 set aligned on a fore/aft plane described by the cylinder centerlines/crank axis and the other set at 90 degrees across that plane. These are the motor related source of the directly applied NVH concerns addressed by way of compliant mounts in all conventional motor cars. I've written elsewhere on the also very intriguing aspects of acoustic excitement of the car structure, but that's off topic here. Seat time as passenger in 2 early Esprits running on biscuits, all mounts in fine nick, engine cover absent, well demonstrated the nature of containing the driving related forces. Hard on throttle: the motor front end rises smartly; hard drop throttle, overrun in gear: the motor front drops down smartly. That's the visible expression of powertrain torques, forward and reverse under load, resolving to equilibrium through containment by all related mounts versus tyre contact traction. To my eye it seems there's a comparatively small role for the trans hangers to contribute in this aspect, as they are an assembly from which the powertrain should have liberty to swing a fair ways fore and aft. That said, failed motor mounts must ultimately result in the hanger bushes being drawn out of healthy form (failed) as a consequence of excess load/displacement. There are also the torque reactions rotationally aligned with the crankshaft axis and the hangers must be vital, along with the primary M/M's, in resolving those. Failed mounts might result in some vertical engine movement due to those forces as well. Back with the fore/aft thrusting forces in terms of the present discussion, it seems that while the M/M's are primary in the task of restraining those one must remember that the trailing arm mounts are also tasked, to a lesser degree I would think, in this regard. So what to expect if the trailing arm mounts are failed? One would hope there to be some sense of squiffy handling perceived, however the very broad stability inherent in all Esprit chassis seems to do quite the job of concealing component defects. Just review how many have reported utterly shot dampers discovered upon disassembly, nary a hint of it while driving. So it's not clear to me how far shot the T/A mounts would have to be in order to effect engine to cover clash. One of the most appealing aspects of Lotus ownership is the way in which the sublime simplicity of chassis design leads the curious (Guilty !!) to explore the pertinent science in depth. In summary, Pete, you will want to review the state of M/M's as you already have, then also take stock of the trailing arm mounts just in case failure there might have taken away the margin to clash between bits. Most interesting thread. Cheers
  16. Hi Pete, At the moment I think my OEM mounts are fitted to a mock-up rig over at a buddy's shop, not readily accessible. Out in my garage there are the bits in the SJ uprate kit (poly) which, though differing in form, might provide something helpful. Not necessarily easy to get at though as I've had to tuck the lot into every open space of the body and shove aside to make room for the bleeding home reno work !! If/when I can haul them out I'll try to derive something approximating the c-c distance between chassis and engine block bosses. Meantime, perhaps some other good soul may chime in with the required measurements?
  17. That's a smart looking motor car, Lez! Regarding ride height your latest pictures don't entirely address the question and, while the earlier pics of the car from that PDF set I posted earlier do show the car at a somewhat raised front end, one can't be sure whether the car had been settled onto its normal ride height. Those shots had been taken either inside or just outside the vendor's garage and it was likely inside the garage where the suspension photos were taken, the car on a lift or jacks. Now that the car has been driven perhaps compare its present stance with those older pics. Cheers
  18. It's not unreasonable to cut perhaps 3/4 of a coil off the fronts of the Federal springs. It's been done on a buddy's car, along with Koni dampers and larger wheels and tires, to good effect. Cheers . . . . read that, " . .. front Federal springs . . ." if you will. Morning coffee yet to kick in.
  19. I'm about 6'1", long legs, and I always found proximity between knees and steering wheel was problematic, whether Giugiaro or Stevens. The interior work should start soon, as home reno is shaping up well enough, and I will be test fitting the seat, column and wheel to the bare shell for confidence in the outcome. The decision to dispense with the seat rails is already made and wheel spacers are easily had on ebay. While not at all as problematic as the Esprit I found reason to rework the seat position in the '64 Elan, to utterly fine effect. It was a matter of tilting the seat via spacer blocks under the front and with leg and torso support much improved thereby it was very comfortable to drive all day, delightful on road trips. The Esprit, like its Europa forebear, starts ahead of the game with the chaise lounge seat form. Success for me will be a simple matter of lowering the seat for wheel clearance, and tilting it to give support under thighs. The wheel spacer's as good as done if that appears in order. Cheers
  20. One fewer Roman Bronze S2 existent as I have a total resto underway and prefer the car other than the RBM in which it was originally painted. Sorry if that's bad news.
  21. Hey Lindz, Thanks for sharing an inspiring account, that's a sweet car! Your opinions greatly parallel what drew me to buying my S2. Can't wait to get it restored and on the road. Long time back, the buddies and I wowed the crowd down in Cali when we showed up for events in '64 and '65 Elans. Drove maybe 1100 miles each way and the memories of those epic trips still bring the gladness, big time. Any serious Lotus owner can travel such distances and so live the journey to the fullest but only if they stay on top of ALL critical components/systems. You are clearly already there. BTW, the wife subscribes to Vanity Fair, in which the August 2014 issue ran a Vuitton ad featuring the Boomerang as a prop. Snatched that up right away for the file cabinet! Cheers
  22. I've had positive experiences with both brands. Interesting that the Sprints are 1.3 kg heavier.
  23. Hello Roland I too gave some thought to the wrap solution when reckoning with the surprising cost of a paint job these days. For perspective, when I had my Elan done in '85 by a local ace the very good deal he offered ( he is celebrated in the region for having done a great many classics over the years ) was $1600 for considerable body finishing and 2K paint. It was a stunner of a result, by the way. Today, I'm told that sum might cover the cost of the paint materials alone for my Esprit. I'm going to stick with paint but were it to be wrapped I might go with a satin white, of all things. I saw a modern Aston Martin in that once and it looked for all the world like it was carved from marble. Cheers
  24. Mrsdoom was LOL upon hearing your latest verse, George. She's just a bit twisted. That Mini kit is just about the sort of thing I'd try as an engine stay, were that on the cards. As stated earlier I'm thinking of trying the SJ poly on the cold side. Exhaust side still to be determined, torque stay not out of the question. Trusting that we are not straying off course in terms of Pete's concerns, it interests me to discuss the matter of NVH as a whole. One mate explored the infamous resonance, well apparent in his and brother-in-law's S1's, through substitution of several silencers. He had fitted a big bore 4-2-1 manifold and DCOE's breathing noisily through K&N filters. The thing made a simply glorious angry symphony of noise at full chat, but the booming resonance was worse, not helped at all by use of a "Turbo" style, reverse flow baffled silencer. Next up was a straight flow, drag race muffler that reportedly worsened the resonance but announced buddy's imminent arrival from quite a distance. What was eventually settled upon was the Supertrapp brand diffuser disc assembly, which emulates the form and function of a trumpet mute. Very compact as mounted on the shortest collector pipe, and most agreeable to the torque output curve with quite the reduction in the resonance! Aesthetically not to everyone's taste, lacking the gaping pipe end bore of more conventional mufflers, though. Cheap and absolutely durable, by the way. One question worth considering is establishing what proportion of the dreaded resonance is down to direct acoustic excitement of the car's light, GRP bodywork. I've got a bare shell on trolley cart in the garage and to tap one's knuckle on most of the panels is to gain appreciation for what a drum we have in these Lotus bodies. It takes just a bit of exhaust fiddling to incite the most almighty resonance into any car, even in all metal unibody form. I once had a shop fit dual path "Turbo" mufflers to a Capri V-6 and it resulted in a head-throbbing resonance on overrun in the lower revs that shook the rearview mirror to the point of uselessness. The typical crossover pipe was then added to little benefit so we reverted to OEM configuration, with the single path for all 6 back to a single "Turbo", and that was not at all troublesome. So I shall be trying to head off acoustic energy early in the scheme of things - e.g. thickly laying on dampening mat to the inside of the exhaust side tank well and vicinity. It is the conventional view that the NVH improvement greatly realized in the S3/Turbo series was down to the revised powertrain mountings and, while that must be true to some extent, one must wonder whether other methods were employed which significantly contributed. The newer p/train mountings fully resolved what was undoubtedly a tendency for the early cars' arrangement to perish prematurely, so that wasn't entirely about the resonance problem. I believe there was a notable increase in weight of the S3 over the early cars, yet the major components were all pretty much equivalent. So thicker body panels? Bulkier acoustic deadening mats? Fair weather beckons me outside to reno chores. Catch up with you good lads later.
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