Red 6 Posted October 14, 2014 Report Share Posted October 14, 2014 I am not exactly sure what we wont agree on since the OP was asking about what lightened flywheel to fit, and for a road car I do not believe I have ever found a more cost effective way of improving the low end performance and driveability whilst not having to modify or strengthen other components to compensate. In my opening response I mentioned that everyone has an opinion about everything and to further add to that a lot have an opinion but no experience of doing what they are expostulating on hence, as James May often describes, the internet is a web of lies. Now as for revs, I had the pleasure of owning a TR6 racing car (road legal but a pig to drive with a 7.5" cerametallic clutch) and was able to experiment and try different things and have personal experience of what driving a British 6 cylinder car at revs up to and in excess of 8k rpm. In the words of the young folk it was truly "super Awesome", and not just the way it accelerated but in the complete aural excitement which accompanied any journey (except in traffic * see clutch type). Now to achieve that kind of performance there was "some" expenditure required the least cost being the ARP big end bolts at £25 each!!!! So nice experience but not for everyday use. I did think of supercharging my TR250 as it had the required low compression pistons and Moss had the kit on special offer, but chose to buy a supercharged car, not a TR, instead of doing it my self and can confirm and agree with you supercharging is the way to go for effortless power delivery and for me 6 years of trouble free enjoyment. So that so it really I do not see where we disagree as I agree with you, and I have a copy of tuning 4 stroke engines by that chap bell and the one by vizard and the really good one on supercharging which seems to spend most of the pages eulogizing about dissipation of excessive heat generated by supercharging! Quote Link to post Share on other sites
Peter Cobbold Posted October 14, 2014 Report Share Posted October 14, 2014 Ah, so you are a convert ! I'd like to see that Moss kit re-jigged to give serious boost, say 10-12psi.( standard is 6). Pulleys and belt mainly. And water injection used to add 10 RON to the mixture. Bell rubbishes WI in his Forced Induction book, but it is now coming back into prominence. I think WI would allow the standard compression head to be used, on 97RON petrol. That's the way 'Im going with the old Wade. Peter Quote Link to post Share on other sites
Ade_TR6 Posted October 14, 2014 Report Share Posted October 14, 2014 Just put water injection on the supercharged toy and re plumbed the charger outlet pipe work to shorten and get rid of the inter cooler. All I can say, to coin modern parlance, OMG... It was quick before but now it's rabid... Supercharging, oh yes I am a complete convert... Quote Link to post Share on other sites
Peter Cobbold Posted October 14, 2014 Report Share Posted October 14, 2014 (edited) Just put water injection on the supercharged toy and re plumbed the charger outlet pipe work to shorten and get rid of the inter cooler. All I can say, to coin modern parlance, OMG... It was quick before but now it's rabid... Supercharging, oh yes I am a complete convert... Ade, I guess the knock sensors were holding it back before!! Which WI system you using? Aquamist? That 10RON gain for 40% WI ( as percent of fuel by mass) is in Jeff Hartman's book: http://www.amazon.co.uk/Supercharging-Performance-Handbook-Motorbooks-Workshop/dp/0760339384/ref=sr_1_3?ie=UTF8&qid=1413314372&sr=8-3&keywords=jeff+hartman You going to supercharge the 6 next? !! Peter Peter Edited October 14, 2014 by Peter Cobbold Quote Link to post Share on other sites
murrayarnold Posted October 15, 2014 Report Share Posted October 15, 2014 Good day all. Interesting reading off course. But if I am not mistaken, which I may well be, a heavy flywheel on 6 cylinder car works in its benefit while cruising. Seeing I do more mid to high end speeds and little time cruising the town centre I have no need for a lightened flywheel. The idea of the fly wheel I thought is the conetic (spelling) energy it produces once it gets going. Instead of worrying about the engine having to turn the flywheel, its actually reversed once cruising where the weight of the fly wheel creates energy while rotating to assist the crank to turn. So basically it depends on ones particular driving styles I would have thought. So if you like doing traffic light grand prix racing I would have thought a light weight wheel would for sure be your cup of tea. But if your a weekend cruiser then I would have thought the original wheel is suitable. Or have I been duped in the past by listening to someone I shouldn't have, which to be honest is likely. Quote Link to post Share on other sites
Alec Pringle Posted October 15, 2014 Report Share Posted October 15, 2014 No duping there, there is indeed a distinct difference in cruising behaviour with a variation in flywheel weight. The lightweight flywheel enables much faster rpm rise in a no-load situation - blip the throttle and it sounds a huge improvement. Off the line the engine has less work to do getting a heavy flywheel moving, so initial acceleration is improved. Conversely, without the momentum of the heavier flywheel, revs will fall away more quickly. That can be a real downside in a car with anything less than a lightning gearchange, and lead to premature clutch wear. A lightweight flywheel is by no means always appropriate for a 1/4 mile dragster, for example. Without a hefty flywheel to smooth things out, idle can be a tad lumpier, or worse. Gear changes may be more frequent, you can't haul 3rd through all the bends so easily anymore, some downshifts to 2nd may be in order. You'll also learn to cruise more sensitively, slight variations in pedal pressure or road incline/decline are no longer compensated for by stored energy in the flywheel. You might not notice on the Sunday doorhandle to the golf club. Your wife certainly will notice on a 300 miles holiday run down the autoroute. No such thing as a free lunch. Cheers Alec Quote Link to post Share on other sites
murrayarnold Posted October 16, 2014 Report Share Posted October 16, 2014 I reckon I will stick with what I have. I am a cruises and left the box racing days behind years ago. And after my car running triple webbers and not engaging high gear and still returning 25 mpg over a weekends long rally, well in could complain. If it ain't broke, don't fix it. buy some cheap thing and butcher that. Like my mk1 escort for example. Ha. oh come on, like I realy left all my any racing days behind, who believed that one. Ha ha. Quote Link to post Share on other sites
murrayarnold Posted October 16, 2014 Report Share Posted October 16, 2014 I reckon I will stick with what I have. I am a cruises and left the box racing days behind years ago. And after my car running triple webbers and not engaging high gear and still returning 25 mpg over a weekends long rally, well in could complain. If it ain't broke, don't fix it. buy some cheap thing and butcher that. Like my mk1 escort for example. Ha. oh come on, like I realy left all my boy racing days behind, who believed that one. Ha ha. Quote Link to post Share on other sites
murrayarnold Posted October 16, 2014 Report Share Posted October 16, 2014 Bugger. I need to read my post before posting. This stupid predictive text is meant to read my mind is it not. Hope you guys can make sense of strange words in odd places in that last post. Quote Link to post Share on other sites
Red 6 Posted October 16, 2014 Report Share Posted October 16, 2014 No No No! Forget any connotations of racing a lightweight flywheel just give effortless driving at low speed and makes NO difference at all to cruising and I speak as someone who drove one for 19.5 years and fitted one to every TR I have ever built (lots) Now to refine this ideological thread a bit there is a lot of talk about light weight flywheels so I think a bit more detail is required as there are light weight and very lightweight or just plain lightened. If you refer to books by people who have actually done this and are respected for doing It and have made a living out of selling the parts they wrote about you will quickly see the optimum weight for a light weight flywheel fitted to a road car, or in the case of Kas Kastner and Peter Cox the amount of material to be removed from a standard flywheel. It is all there in B+W. However the final say as to whether to do it or not is up to the individual, all they need are the facts and not conjecture. (and maybe a test drive in a 6 fitted with one:-) I rest my case. Quote Link to post Share on other sites
Guest ntc Posted October 16, 2014 Report Share Posted October 16, 2014 I rest my case with experience of motorsport ,having seen one poor soul lose his leg and another coming though the bonnet . Quote Link to post Share on other sites
Alec Pringle Posted October 16, 2014 Report Share Posted October 16, 2014 There's nothing wrong with the judicious lightening of a production flywheel, within the sensible limits of good machine shop practice as applied to any such casting, new or used. Subject of course, to fitting a properly balanced flywheel to a properly balanced engine and clutch and then rechecking the whole assembly. Unfortunately there are folks who fail to appreciate the basics of the exercise, and that is when disaster is likely to strike. Like Neil, I've seen it happen, and on a couple of occasions with life changing effect. Cheers Alec Quote Link to post Share on other sites
TriumphV8 Posted October 17, 2014 Report Share Posted October 17, 2014 (edited) With no doubt you get more torque with heavy mass in the moment when you slap the clutch but when putting high load to the engine constantly from what reason should the pistons know that there is a light flywheel mounted? -Torque output of engine is not affected by flywheel weight- I took one of the lightest flywheels that were availiable for me and that was the Fidanza. I used the bolts from ARP from the chevy engine with ARP lube. That is now perfectly running for 7000 miles. Fitted is EFI fuel injection and a 290degree cam and 2.7 litres. Engine is driven under cruise conditions from 1200 to 3500 where my wife picks the car for shopping some times and full load from 2000 to 6500, redline is 7000. The rotating mass is still felt too heavy although I must admit that some humming is noticed below 1500rpm and full load that started formerly at lower revs. But who does that? If power is needed below 1500rpm I would prefer to shift! By the way the engine feels crispy and responds to pedal rapidly. It feels like 20 extra HP at the crank. Also shifting back before the corners lets the engine respond more easy and makes the rear more stable withou paying too much attention to that. All in all I would recommend a lighter proper crafted flywheel as a basic tuning unless you intend to move a plow or transport horses or cows to a fair. Edited October 17, 2014 by TriumphV8 Quote Link to post Share on other sites
murrayarnold Posted October 17, 2014 Report Share Posted October 17, 2014 What, no more cows in the car! Ah. Bugger that only leaves the chickens. So much to consider ha ha. Only joking off course. I have more than just chickens. Quote Link to post Share on other sites
dblenk Posted October 17, 2014 Report Share Posted October 17, 2014 think we might have found the new badfrog humour here Quote Link to post Share on other sites
Stanpartmanpartwolf Posted October 17, 2014 Report Share Posted October 17, 2014 As guilty as the rest of you..... In response to the OP, who has long been forgotten after 39 further postings: short back. Buy a steel "spider" 8.5" variant, fit a new ring gear & dowels, plus four quality ARP bolts & lube. Balance will be fine. Clutch covers are factory balanced to an acceptable degree. There is no downside whatsoever to fitting a lighter flywheel to a 2.5L Triumph engine. Thanks to Red6 & TriumphV8. "Lumpy tickover" my @rse. Cheers etc SPMPW Quote Link to post Share on other sites
Alec Pringle Posted October 17, 2014 Report Share Posted October 17, 2014 Lumpy tickover your @rse Jon ? Give over lad. Half the bloody PI cars at Malvern vibrate on tickover to an extent that would get any red blooded lass on the bonnet wound up in ten seconds flat. With that level of piss poor tuning, fit a lightweight flywheel and the lumps would be firing out bolts . . . . Cheers Alec Quote Link to post Share on other sites
Andy Moltu Posted October 18, 2014 Report Share Posted October 18, 2014 Just when does anyone drive their car at idle? Quote Link to post Share on other sites
Andy Moltu Posted October 18, 2014 Report Share Posted October 18, 2014 So Triumph got it wrong ? boll!!!!! Absolutely - Triumph got every engineering call spot on 100%? It wasn't just poor production that saw the British car industry wither and die. Financial pressures contributed to engineering compromises, Luddite thinking and internal politics saw them being left behind in engineering and production terms by the Germans and Japanese. Naturally the TR range was exempt from us using hindsight to question the engineering. Separate chassis in a monocoque era. Heavy iron heads and blocks and overhead valves.. sure Triumph got it all right and who are we to question? Quote Link to post Share on other sites
murrayarnold Posted October 18, 2014 Report Share Posted October 18, 2014 I may drive classic cars, but I still have a head Full off nonsense. Hey did you guys see my page in the october issue of the magazine. tr6 in croatia. yes, that's me Quote Link to post Share on other sites
TriumphV8 Posted October 18, 2014 Report Share Posted October 18, 2014 Half the bloody PI cars at Malvern vibrate on tickover I made a lot of investigation if tickover is the point where the throttles just start opening. Very critical is the range of 1800 to 2000 rpm with no load at the CP engine. As I have an electronic injection and a wideband controller I could watch whats going on and what is a remedy to kill that bad response to throttle. First the main reason was the throttle plate bearing and the linkage. Second at tickover the engine needs a rich mixture around 13.5 AFR or richer when plates are worn. Remedy was to fit ball bearings from Model cars to the spindles and change the linkage complete to silver steel axle from model cars with needle bearings. The plastic bearings are "cheap and dirty" especially the one in the middle that has to be cut to fit! The flywheel was absolutely innocent! The engine runs so smooth with a fine balancing and the Fidanza flywheel similar to a BMW straight six. Quote Link to post Share on other sites
Stanpartmanpartwolf Posted October 23, 2014 Report Share Posted October 23, 2014 Just to wrap this one up....I'll maybe let Neil comment, as words fail me here: Quote Link to post Share on other sites
Guest ntc Posted October 23, 2014 Report Share Posted October 23, 2014 No need to let me chap would you fit one on a road car? Quote Link to post Share on other sites
TRTOM2498PI Posted October 27, 2014 Report Share Posted October 27, 2014 Yes, I have one, and no issues at all. ? Fitted in 2011. X4 APP bolts used to attach, with locktite. Those who have seen my car, know how quick it is, and how it is driven etc. All the best TK. Quote Link to post Share on other sites
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