| Author | Message | ||
     Richard Treacy Grand Master Username: richard_treacy Post Number: 570 Registered: 4-2003 |
Robert, Is there enough information below for you to plug into your model ? Unfortunately I forget the BHP on the dynamometer and the printout is not here, but at the wheels it was less than 200. I did the camshaft and cylinder head modifications back in the mid ‘80s a few years after I took my first proper job. I did it all mainly as an experiment as the car was running absolutely fine. As a core camshaft, I bought an as-new spare from Brian Thompson in the UK, and brought it home in my hand baggage. That would raise a few eyebrows today ! After mapping the original profile and finalising the design I wanted, I did the rounds. I tried two Sydney camshaft grinders. The first was a highly reputable volume producer, and not at all interested in my project. Waggott Cams on the Hume Highway at Lansvale, my first choice anyhow, were great. A young man called John Byrne at Waggott Cams gave me his master patterns to peruse for a few hours in his office. I determined that the Waggott master patterns 210 (inlet of a Jaguar pushrod motor pre-XK) and 192 (exhaust of some Buick) are almost exactly the same as for the Bentley. John then took on the job to grind the camshaft to my specification and to hardness test it afterwards. Once the master has been determined, the patterns are set up on the machine for grinding. Essentially, all that needs to be done then is to dial up the lobe lift and other tweaks you desire, and grind away automatically. I had calculated that the exhaust valve springs would be fine, but that the inlets would bounce at around 3600 RPM with the higher valve drop rate, and road tests proved that almost exactly correct. Valve bounce started at around 103 km/h in third gear, before the upshift point into 4th, so I replaced the inner springs a few days later. I had already determined two specs for revised inner valve springs to fix that, one with 6 coils and the other with 6 ½, and had had a few dozen made of each. I decided on the softer 6 ½ coil ones as these would be easier on the lobes. I have attached the results of the calculations and measurements. The new springs sure work fine, and the valves do not bounce at the 4250 RPM redline. That was an in-situ change of course. ________________________________________________________________ Engine Data Bentley chassis No. B174UM Engine No. B212U Engine Type: B61 Bore: 3.6290 inch (0.004” oversize) Stroke: 4.5” Nominal capacity 4576cc Full length cylinder liners Cylinder head gasket: UE5053 steel Cylinder head: basically unmodified chamber shape Nominal compression ratio: 7.3:1 Pistons: REPCO part number TC131, injection diecast, tin plated, solid skirt, reduced skirt length, lightened, modern ring pack Main bearings: 0.020” undersize Bigend bearings: 0.010” undersize All rotating motor and drivetrain components dynamically balanced individually and finally as an assembly Vibration damper: Ferodo friction plates Valve gear: standard arrangement apart from stiffer inner inlet valve springs Valve seats: new austenitic inserts in head and block Valve guides: custom aluminium bronze inserts in inlet guides, press ball rolled to size in-situ; custom made aluminium bronze exhaust guides Spark plug inserts: custom made magnesium bronze Inlet Valve Seals: Crane Cams teflon spring loaded Camshaft: Waggott grind, Waggott master 201 and 192 (base master profiles are Jaguar pushrod and Buick); tappets cam ground to match Hardness: tested to 60 Rockwell after grinding and finishing Valve Timing, degrees: Inlet opens 37 before tdc Inlet fully open 112 after tdc Inlet closes 81 after bdc (261 after tdc) Inlet duration 298 Inlet lift 0.325” at lobe, 0.435” at valve Exhaust opens 58 before bdc (238 before tdc) Exhaust fully open 109 Exhaust closes 20 after tdc Exhaust duration 258 Exhaust lift 0.370” OverlapCentre 8.5 Overlap 57 Tappet clearance 0.006” inlet, 0.012” exhaust Inlet valve springs (pack of two springs, inner spring 6 ½ coil), 53lb closed, 138lb fully open Exhaust valve springs: standard Carburettors: Two SU H6 automatic choke ¾”, 0.1” jet, SN needles selected on dynamometer-exhaust gas test, export oil bath air cleaner Exhaust: dual stainless steel, reduced back pressure (approx. 30%) Nominal ignition timing (measured dynamically): 7 degrees BTDC on idle, points dwell 42 degrees; advance curve standard. Fuel 98RON unleaded. Transmission: Original GM-built X53-48; pressed steel sump and sideplate, compensated servos, late S1 inertia ring and flywheel (all original equipment), second-speed starting implemented at last overhaul. Final drive: 12:41 export ratio    | ||
| David Gore Moderator Username: david_gore Post Number: 409 Registered: 4-2003 |
This information is exactly what this forum is all about and I thank Richard for disclosing information that others would not do as often stated in their posts - we all appreciate the work, expertise AND cost involved and the fact that Richard has saved others unnecessary expense through his generosity. There is an old adage; "It is better to give than receive" and it is my belief Richard will receive future benefits in his life as a consequence of his assistance to others. To the others "put up or shut up"; if you are not prepared to contribute in a meaningful way or refrain from "bullying/disparaging" other participants who do then please stop using this site and go elsewhere where your "talents" are appreciated. | ||
| John Dare Grand Master Username: jgdare Post Number: 183 Registered: 12-2004 |
I note with interest the kph "shift" point in the old "GM" auto. and a "REDline" (top) at 4250 rpm. My R-type is one of the rare and desirable manual models, which tends to "invite" (if I may use that word) letting it "run out" a little, before a careful gearchange more sympathetically executed than say a "blink and you wont see it" a la 911 style. I have often contemplated a rev. counter so I can keep track of things, but WHERE to mount it?. A local, long term, "R"-type owner, assured me that his car had an original FACTORY installed tachometer (see the "R" type factory parts manual!) his being installed upon a "custom" wooden (dash grain "matched" etc) blank-off/ "face plate" in the RH "cubby box" receptacle. I dont know if that is "factory" correct mount, and in any event, I have a discrete AM/FM radio/tape player in that particular location. Because of increasing traffic and todays "driving" (with all of its distractions!) I fear I might have to go to "Autobarn" to buy a "Speco" shift-light tacho., dash "cap rail", mounted (maybe just above that funny little black turn signal lever?) being the one that never seems to stay "on" long enough. I believe Ive seen these "tachos" advertised in "Street Machine" magazine. Apparently you simply programme/"dial"-in, your chosen "shift" point, so I will ask the friendly man to set mine at "safe" 2-3 & 3-4 rpm shift points for, being mindful of a 60 yo engine design, I like to be on the good old side of "caution", even though John V. performed such a professional rebuild upon it, using many new parts too. Even a "re-profiled" camshaft, courtesy of Wades, recalling that when I collected it, the salesman quipped that it was a "3/4 race" (?) job, with extra steep "slopes". Maybe also a rev."limiter" rotor (if I can find or adapt one) to ensure a "cut-out" at the RED line "MAX", which maybe I can "set" for say, 415O, keeping that extra 100 rpm as a sort of "secret" little reserve for emergency use. I would also be able to see how many revs. I "lose" (long stroke/heavy crank etc) during the actual gear "change" process, so that would be an added benefit. As they were described (quite rightly) as "The Silent Sports Saloon", what a pity a tacho. didnt come standard (as per the "R" type "Continental"!) since it would have only resulted in a marginal cost increase. If anyone has an ORIGINAL "tacho" (per parts manual illus.) I would like to hear from them. | ||
| Robert Chapman Grand Master Username: shadow Post Number: 171 Registered: 5-2003 |
Thanks Richard great detail, Just to check for modelling, are the valves standard size. What was you reason for choosing these particular spec's and where did you expect the gains to occur. Since you were having new pistons did you consider increasing the comp ratio.(I will model a seperate run at 8.5:1 with your new cam spec's) This will get me out of painting for hours! | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 574 Registered: 4-2003 |
Robert, I was hoping you wouldn’t ask but here goes. The aim was to preserve torque around 1500RPM, whilst giving increased torque in the higher engine speed ranges. I wanted not to do a wholesale hot-up job, but to make useful gains which do not change the character of the car markedly. This excluded lightweight roller tappets, pusrods etc. In short, I wanted to achieve what I could within reasonable parameters, in other words to reap the low-lying fruits. This was before Lotus 123 was in widespread use, and it was terribly slow where it existed, so I did the simulations on a PDP11 using Runge-Cutta algorithms written in Fortran. It would be far easier today on a PC using Excel. First, the parameters. An increase in maximum engine rpm was out of the question given the extensive research on the harmonic vibrations of these motors. They explode at not much above the 4250 redline. Many did that way on test at Crewe. Looking at the restrictive porting, I couldn't really see much to be gained by increasing the valve sizes without a lot more non-reversible work. Sourcing oversized valves would not have been difficult as I had a few standard-sized sets made for me to order by a company called Dreadnought Valves, now closed down sadly, in Sydenham. They are austenitic, with stellite tips. Also, as I expected the inlet valve mass to be critical, I didn't want to increase the weight of the valves. Larger valves may also have adversely affected low speed smoothness and torque. Sodium filled lightweights were certainly possible, but gee I wanted a car which was basically stock and undetectably modified unless striiped down. I didn't wish to do too much to my spare RE19451 cylinder head which is not reversible either, so had the combustion chamber welded up a little and polished. That took it from nominally 6.75:1 to 6.9:1. The rest came by using the UE5053 (S1) steel cylinder head gasket. An S1 head would have been a better starting point but I did not have one. With better porting and the possibility of a late head with even better porting and larger valves, that would have been the way to go. I almost bought a complete S1 motor to install, but figured I preferred to retain my own block and keep the car looking as original as possible. That included all ancillaries, so I left my expensive new manifolds untouched but had a new exhaust system made up. It is made from thick-gauge stainless steel with custom made free-flow boxes which damp the noise as well or better than the originals. The boxes were made in by a large firm in Lithgow, but I can’t remember the name of the firm. The downpipes connect to the front boxes by flexible bellows so the manifolds are never stressed or broken as many have been. Next was to choose an overlap and timing. Using the standard cam lobe profiles as a starting point to limit material removal and rehardening on grinding, and measuring up the cylinder head and exhaust valve geometry, I did some calculations as best I could. With the large physical distance between the inlet and exhaust valves, it was clear that an increased overlap was a sensible option, and would stress the camshaft less than increasing the lift dramatically. This was bearing in mind that early MkVIs had a high lift cam which wore out after 90,000 miles or so in 90mph Continental driving. I wanted their marked extra performance over later cars, but without the reliability problems of using really heavy inlet valve springs as those cars did. Limiting spillover between inlet and exhaust ports at low RPM, high throttle opening was the key. At 60 degrees overlap, the gas flow Runge-Cutta calculations showed that spillover started to increase exponentially. Put simply, low end performance, within the accuracy of the assumptions, dissappears very quickly as you start to exceed a 60 degree overlap in this F-head motor. Any increase to below 60 degrees has a negligible effect. The very marked knee-point at 60 degrees was very encouraging, so I figured it couldn’t be too far wrong. Allowing for tappet clearance, I therefore aimed for 55 degrees, so the camshaft itself I froze at 57 degrees overlap. The timing was determined by the gas flow in the same manner: I ran a Runge-Cutta and plotted the flow, finding the optimum point at 2,500RPM to be 8.5 degrees before tdc for the overlap centre. At 4,000RPM it was closer to tdc, but that started to cause poor low-end gas flow below 1500RPM, so I stuck with 8.5, and reconfirmed it once I decided the valve lifts. Determining the lift was then easy given the constraints I had set. I set the exhaust profile so that the exhaust valves would not bounce until 4350 RPM. That was simply a mass-acceleration calculation (no simulation required) using the spring rate and allowing for a little valve stem friction. Allowing the spring to keep up with the lobe when closing gave a 0.370” height limit so not to exceed the lobe rear slope limit. It was clear that the original inlet valve spring rates would be too low to do much, so I opted for a lift which would not bounce until 4350RPM, but with a spring force of maximum 150lb fully open. I had boned up on camshaft wear vs load, and it appeared that, with the width of the inlet lobes and a Rockwell hardness of 55, wear rates would start to accelerate at around 240lb, or 175lb at the valve with the 3:4 rocker ratio. That determined the lobe closing slope and lift possible, 0.325” with a 140lb spring pack. I did calculations on two reasonable spring combinations, either of which would do, and chose the 6 ½ coil inner as it is easier on the lobes than a 6 coil. I am very pleased with the result, although it has only travelled maybe 40,000 miles since as the car is unfortunately far from where I live. There is no perceptible loss of low-end torque or smoothness, and it certainly is more powerful. From memory, we recorded an increase of over 25 bhp on the dyno. By the way, you mention high compression pistons. That would have meant having two types: a left and a right for alternate cylinders. They would have needed to protrude into the combustion chambers and would have been a very odd shape. It has often been written by the designers that these motors respond to high compression with roughness and not much else, so I didn’t push very hard in that area. Also, standard flat top pistons have no risk of fouling the inlet valves with a 0.325” lobe lift (0.435” valve lift). | ||
| Robert Chapman Grand Master Username: shadow Post Number: 172 Registered: 5-2003 |
Hi Richard, My simulation testing has confirmed(not suggesting you needed it) that you have achieved what you set out to do. Torque was reduced very slightly at the lower end but moved up the rev range by 500rpm and achieved the same max as the original cam. BHP increased by 18% overall. Interestingly I could not get an increase after .375 of inlet valve lift,I can only presume it was caused by the restriction of the ports. When I mentioned increasing comp ratio I was not thinking of changing the shape of the crown, rather increasing there dia (bore oversize). My thoughts were to increase cylinder volume and comp ratio in one go, but calculation showed the increase to be minimal. | ||
| Robert Wort Grand Master Username: robert_wort Post Number: 103 Registered: 12-2004 |
Hi Robert, I would love to see how your simulator works, Is it possible to download a model in the fashion that Tord Samdal did with his hydraulics model? | ||
| John Dare Grand Master Username: jgdare Post Number: 188 Registered: 12-2004 |
Hi Robert. Amazing is it not, that R-R engine cam designers, early in the post war period, eventually achieved the best OVERALL "all round" cam specs., WITHOUT the use of IBM "laptops" etc. At that time, Englands only computer was probably the one at Bletchley Park, which at least helped prevent the premature acquisition of Crewe. As clearly demonstrated, one example of personal experimentation (years later) merely results in the best useable torque being available further UP the rev. scale, thereby obliging one to drive FASTER to obtain the fundamental benefit. Due to the overdue global trend toward REDUCED speed limits (hear, hear!) such benefits are therefore not likely to be readily or fully realized from a practical driving perspective. Even though I have the desirable and more flexible, manual trans. "R" type, I believe I will be able to forget about that "tacho" with its "red" lines and all, simply relying upon my speedo, comfortable in the knowledge that at normal road speeds my engine is operating at its optimum; as its learned "scientist" designers so intended. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 584 Registered: 4-2003 |
Thank you, Robert. It is always encouraging when theory and practice coincide. The gains in the low to mid range are very useful, especially in the important 60-90km/h speed range in top gear, and as you confirm, the torque at low speed is not compromised. Of course, when overtaking in third gear, the 60-100km/h performance increase is extremely useful. Unlike modern cars, it is still not in any way oriented towards high engine revolutions. Sir John: you imply that R-R got it right in the first place. By using their rough guesswork, they made a pig's ear of the design in reality. The early MkVI's went like stink, but were unreliable in the camshaft department. That's why the later MkVI's and onwards had such a conservative and sub-optimal camshaft design. Why it stayed that way I will never know. At leat with the advance of the automatic transmission they could have revised the profiles to take advantage of progress. RT. | ||
| Robert Wort Grand Master Username: robert_wort Post Number: 105 Registered: 12-2004 |
RT,JD, I will agree with John on one thing though about computers. Marvellous things that they are, many vehicles nowadays are now computer designed to maximise aerodynamic efficiency. As a consequence most modern vehicles look pretty much the same and with no (or very little) human input, modern vehicles rarely exhibit the WOW! factor anymore. The new Bentley GT maybe technologically advanced but it doesn't have a patch in the beauty stakes as compared to the R Type Continental or the Flying Spur. | ||
| David Gore Moderator Username: david_gore Post Number: 414 Registered: 4-2003 |
Robert, with due respect I suggest the current styling [which I absolutely and unequivocably detest] is not the fault of the computer but the inevitable outcome of a world where the lawyers and single-issue extremists have imposed conditions which no longer allow any expression of individuality. The quest to minimise fuel consumption has lead to application of basic aerodynamic principles to the outer shape of the car - there is one optimum combination of these principles derived from experimentation/wind tunnel testing and this has been adopted by the manufacturers. All the computer has done is to remove the drudgery of repetitive calculations for the scientists and the tedious hours at the drawing board for the engineers. Thank heavens for these mercies!!! | ||
| Robert Wort Grand Master Username: robert_wort Post Number: 107 Registered: 12-2004 |
Hi David, As my answer is risking going off topic, I have started a new thread in the General Topics Section under the heading Something different. | ||
| Ashley James Unregistered guest Posted From: 84.92.55.251 |
R-R made quite a few different camshafts for the B60 although I think they only changed the part number three times. Like most manufacturers of the time, they were trying to minimise wear and maximise power. Of these, the one to have is fitted to late automatic R's, S1's and cloud's, it has 0.035" more lift on the exhaust and the lobes are full width rather than tapering slightly towards the top. They also use 8 instead of 4 fixing bolts. John, if yours is a manual car it may have the less powerful cylinder head, Later cars and most automatics shared the casting with the Continental (RE19451 I think) and 0.030" can be shaved off them to raise power a bit. This explains why the automatic cars were slightly faster than the manual ones. The Radford Countryman Cars often had the revcounter in the RH glove box as you describe. Trevor Lewis has one (old South Wales!). Factory records show that the max rpm the engine would run at on a test bench was 4880 and if they did it for a minute, the sump came loose, the main bearing caps moved around and so on. I think they even broke cranks. This speed dropped to 3880 rpm if the sludge traps were full. For this reason the military engines were governed to 3750 and to me, it would seem prudent to treat this as a maximum. With the later high ratio axle that was fitted to most of the cars sent to Oz, 3000 equates to 74 mph, hence my suggestion that 70 mph was an appropriate cruising speed. The R Continental gives about 9 bhp more than the twin system and is slightly noisier. I fitted a slightly modified one to my 4.25L MKVI and it now is as fast as my 4.5L car. It is very slightly noisier at about 30 mph. I do hope this is of interest. (Message approved by admin) | ||
| Ashley James Unregistered guest Posted From: 84.92.55.251 |
R-R like every manufacturer at that time were struggling to get maximum power and minimum wear. Early MKVIs had neither, they were 2.5 sec slower to 60 than the late ones. They even had valve bounce at tick over under certain conditions! The camshaft was changed about six times and the part number three during the life of the B60. The one fitted to late R's and S1 and Clouds being the best and recognisable by having "quietening ramps" and 0.035" more lift on the exhaust. The lobes are full width too and it is fixed with eight instead of four bolts. (Message approved by admin) | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 585 Registered: 4-2003 |
Ashley, Most 4.5s delivered in Australia, MkVI included, have the RE19451 6.75:1 head, as the fuel octane rating was higher than in Europe. I have a spare 6.75:1 head I bought from Brian Thompson in the UK in 1982, and also a spare 6.4:1 which I bought in desperation in Melbourne in 1980, so they were presumably not limited to specific markets. However, I guess that the 6.4 head was from a secondhand import. It has barely been used. The camshaft originally fitted to my R-Type is the later R-Type automatic one, as is the spare I had ground and fitted along with new timing gears. As you point out, they both have 8 studs, which is useful when setting the valve timing accurately. I toyed with replacing the studs by setscrews as they are such a nuisance. All the data I refer to relates to the camshaft fitted to the last of the R-Type automatics. It is interesting that later (I presume that you still refer to 4 1/4) MkVI cars were faster than the early ones. When the very early high-lift cam was dropped (around C-series), the performance dropped significantly, as witnessed by road tests of the period (0-90MPH took 10 seconds longer I recall). Most of the high-lift camshafts were replaced in the early 1950s under warranty or otherwise. Are you referring to the very early cars or cars around the D-Series as being slower ? Presumably there was indeed an intermediate camshaft design which recovered the performance. Of course, mid-series the twin SUs were increased from 1 1/2" H4s to 1 3/4" H6s, which accounts for some performance increase. As for speeds, I do think that you are safely conservative. The R-Type automatic runs 25.25 mph/1000rpm with 6.50x16 tyres and 12:41 axle in top, and there is negligible fluid flywheel slip to reduce that. At the preset maximum upchange point of 65 MPH into top gear, it is very comfortable running at just 3733rpm in third gear. In top gear the same engine speed is at 95MPH (1.45:1 third gear ratio). That is all academic today with highly sophisticated speed traps everywhere and a motorway speed limit of just 110 km/h (68MPH). It was rather useful 20 years ago when I used to do regular 600km weekend round trips on the Hume Highway in the R-Type. In over 400,000 miles it never suffered under such gentle treatment in the slightest. | ||
| John Dare Grand Master Username: jgdare Post Number: 189 Registered: 12-2004 |
Thank you Ashley for yet a further insight into these remarkable and gentlemanly cars. I believe that my car has the so called "later" cyl. head and in any event, I have a spare which certainly is, having had the eroded water passage holes re-sized, face resurfaced etc., it looks "new" sitting under the bench as a contingency spare. I have owned many cars and still have an assortment of such, most of the "older" ones having what I might loosely call a engine "sweet spot" which in B10TN, appears to be around the 70mph speed which you have indicated as appropriate. Irrespective of speed limits, traffic, cross winds ( it likes to get UNDER those huge front wings!) everything seems to be in harmony at that point, whereby intense driver inputs whilst probing engine "red-line" limits, are non issues, allowing one to perhaps admire some of the passing scenery. The 4 door saloons are patrician and gentle looking cars, which, in my opinion, look ridiculous (and always did) being hurtled along as if there is no tomorrow. Conversely, a DB5/6 or 308 etc., looks silly when being sauntered along as if you are trying to "save" petrol!. If however, I do develop a "Go fast" urge, I simply have an "Earl Grey" and a lie down, or start out in the 911 until it has passed. ps. If you were ever able to post a picture of the factory rev. counter (Radford etc) I believe it may be of interest due to its rarity and might allow selection of a visually compatible (non genuine) instrument to serve the same "protective" purpose. Thank you. | ||
| John Dare Grand Master Username: jgdare Post Number: 191 Registered: 12-2004 |
Further to. When referring to his long owned Mark 6, respected member Mr.Tony Ward, states; "these engines really dont like being pushed into the 3000 to 4000 rpm range". Source; "Praeclarum" Feb. 05: column 3, at page 4462. | ||
| Ashley James Unregistered guest Posted From: 84.92.55.251 |
The revcounter used in the Radford Coutryman is exactly the same as in the R Type Continental (Message approved by admin) | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 550 Registered: 4-2003 |
Here's a rev counter on an R-Type Continental..... at 128mph and 4250rpm especially for John's benefit.  | ||
| David Gore Moderator Username: david_gore Post Number: 394 Registered: 4-2003 |
Near Canberra if my identification of the countryside is correct? Good to see a car being used for the purpose it was designed for and the "Prophets of Doom" can go get a life and lead by example rather than trying to legislate their opinions on others who do not agree. | ||
| Ashley James Unregistered guest Posted From: 80.229.46.15 |
Having read this thread I thought I might add some information that may be of interest. R-R like all manufacturers of the time were struggling to get cam shapes that lasted and provided sufficient power. The early "high lift" cam did not give more power, it simply wore out quickly. By increasing the duration and decreasing the lift, they got more power out (for R-R read power as torque)of the later cam. Although there were only three part numbers, there were about six different cam profile changes. They had tried a series of profiles before arriving at the one in the late R's and S types. This one is recognisable by having 0.035" more lift on the exhaust lobe than the manuals say, having full width lobes and eight bolts holding the gearwheel on. Tests in the factory showed that a perfect 4.5L crank would rev(if unrestrained on a test bench) to 4,880 and that after about a minute, the sump bolts had loosened the main bearing caps had been moving around and even cracks appeared. They also found that once there was crap in the sludge traps, the same thing happened at 3,880 rpm. Military versions were governed to 3,750 rpm and it is why I suggested a max cruising speed of 3,000 rpm for our cars. As John's car is a manual it may not have an RE19451 head on it. The autos tested faster than the manual because of the better head. a slightly lower compression version of the one on the Continental. It is not a good idea to raise the compression on the earlier heads as they tend to run rough and produce no more power - hence R-R developing the later version. The Continental exhaust system gives 29 more bhp than the single system fitted to the 4.25L cars and the Dawns and the twin system 20. I've fitted a modified Continental exhaust to my 4.25L car and it is now as fast as my 4.5L MKVI so the difference is considerable. There is slightly more noise at 30mph. I hope this is of interest (Message approved by david_gore) | ||
| John Dare Grand Master Username: jgdare Post Number: 190 Registered: 12-2004 |
Thank you Ashley for your confirmation of Tony Wards earlier observation that 4000+ revs per min.(with piston speeds of 3200ft/min.) approach the danger/IMPLOSION area for these old engines of old design. That aside, I ask, is it responsible to suggest that speeds of 128 mph are acceptable upon Australian (see "Canberra" etc) roads? | ||
| Ashley James Unregistered guest Posted From: 84.92.55.251 |
I have to submit my postings for approval because I am not a member of the RROC. Because quite some time passed without my posting appearing I wrote again - even explaining at my third attempt what had happened and that only one was required, however just like the buses in England, you wait for ever and suddenly three appear at once - I apologise for unintentionally boring you all witless. I have to say that in no way would I wish to tell anyone how to use his car - I was merely quoting from information gleaned from Company records. Hi Ashley, Our apologies for the confusion as we have been going through some significant changes on the website - you do not have to be a Club member to get direct access; just submit a registration request and you will become a registered user with the same privileges as everyone else. Regards David (Message edited by david_gore on February 22, 2005) (Message approved by david_gore) |
