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Post by Simon Crabb on Oct 2, 2008 13:55:58 GMT
Okay, a constant mystery to me, where should one measure droop to? The bottom of the wishbone? The bottom of the hub carrier? And then if one has any kick up or anti-anything where do you measure to then?
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Post by lesbaldry on Oct 2, 2008 14:07:21 GMT
Thats very fascinating Ed...get you head round this..you dont change droop much?..I do!(weight transfer for braking and to get more chassis roll/grip)...Bashley 4/2 droop 5/6mm ride hight..Cotswolds 4/4droop 6mm ride hight but with totally different roll centers to Bashley,West London 6/5 droop 5/5mm ride hight,roll centers ,between the above..nearly the same springing for all three tracks apart from west London,slightly stiffer fronts...Driving style,s/chassis differences??? And befor someone asks ..how do you get more chassis roll by adjusting the droop with the same springs??....remove roll bars and move shock position and or roll centers to allow roll but will need more droop to keep wheels on the deck!
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Post by lesbaldry on Oct 2, 2008 14:47:08 GMT
Okay, a constant mystery to me, where should one measure droop to? The bottom of the wishbone? The bottom of the hub carrier? And then if one has any kick up or anti-anything where do you measure to then? From the most outer point of the lower arm/wishbone on 99% of chassis,s,Team Magic been the odd one out..kick up/squat/dive is normally done by set shims/spacers of around 1mm thick or different depth wishbone pivot blocks/mounts (Xray)to tilt the wishbones..as for correct measurement, Im not sure but It does not need much to give a visual effect..2mm max??? If I remember correctly a 1mm shim under the front pivot block on the front wishbone of my Scythe gave around 2deg kick up and increased the castor from 4 to nearly 6 " it made the car understeer!! "..the reverse would be anti dive ( A/D dont work well at all at Bashley )...Mark T has play,d with anti,pro/squat a bit and may well be able to explain the effects(same adjustment as above but on the rear wishbones....this is not worth worrying about for the new driver as a change track side with these adjustments will always need the droop reset!! it will also "too a degree" alter the roll center....just more to confuse the mind
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Post by TryHard on Oct 2, 2008 15:12:05 GMT
Indeed, must be something like that les.... Then again, the 416 just works (like I said last night, all I changed in the end to get the car working indoors was tyres and moving the rear shocks in... that was from my latest bashley setup!). I honestly hardly ever touch droop, tend to make other changes on the car (roll centres, wheelbase and shock positions at the moment). As you say, when the car hits a droop screw, it effectively piviots around that point (be it in roll, or pitch), hence why the more droop actually helped round southend As for measuring droop, I use a Yokomo gauge, under the chassis, then to underneath the hinge pin point. I know this isn't quite right (the most accurate method is to take the wheels off, put the it on a flat plate, then measure to the top of the wheel axles using a vernier), and I really should take it from the middle of the arm when running kick-up/anti-dive, but well erm... no excuse! On the tamiyas, 0.8mm of shims equated to a 1° of angle on the arms... thats for a 46mm long hinge pin. I'm running 0.5mm less on the rear block at the front at the moment, so effectively have about 0.6° kick-up. Ed
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Post by TryHard on Oct 2, 2008 15:20:47 GMT
To go with les' altering roll centre comment, heres a little excel sheet I made up. Basically it's a static roll centre calculator for the 415. Now, if you adjust the shims underneath both the suspension blocks, you obviously alter the roll centre. This also applies, to a lesser degree, when adding kick-up/anti dive... have a play and see what happens www.thard.co.uk/download/file.php?id=85Ed
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Post by lesbaldry on Oct 2, 2008 15:24:43 GMT
Indeed, must be something like that les.... Then again, the 416 just works (like I said last night, all I changed in the end to get the car working indoors was tyres and moving the rear shocks in... that was from my latest bashley setup!). I honestly hardly ever touch droop, tend to make other changes on the car (roll centres, wheelbase and shock positions at the moment). As you say, when the car hits a droop screw, it effectively piviots around that point (be it in roll, or pitch), hence why the more droop actually helped round southend As for measuring droop, I use a Yokomo gauge, under the chassis, then to underneath the hinge pin point. I know this isn't quite right (the most accurate method is to take the wheels off, put the it on a flat plate, then measure to the top of the wheel axles using a vernier), and I really should take it from the middle of the arm when running kick-up/anti-dive, but well erm... no excuse! On the tamiyas, 0.8mm of shims equated to a 1° of angle on the arms... thats for a 46mm long hinge pin. I'm running 0.5mm less on the rear block at the front at the moment, so effectively have about 0.6° kick-up. Ed Hey Ed Pete must be pulling his hair out and foaming at the mouth by now with confusion..he,s not even a driver ,just trying to get his head round things for Craig...Stick to basic's even Ed and I are starting to become confused.. ;D ;D ;D
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Post by lesbaldry on Oct 2, 2008 15:43:11 GMT
In my very honest opinion from the bottom of my hart or is it the hart of my bottom ...Pro squat,anti dive ect,ect may be only effective for you if your are a top driver running a Mod car on a specific track....For us mortals as club men "trust me " dont even bother to waste your time too much on this!!
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Post by yellowshark on Oct 2, 2008 18:22:58 GMT
In my very honest opinion from the bottom of my hart or is it the hart of my bottom ...Pro squat,anti dive ect,ect may be only effective for you if your are a top driver running a Mod car on a specific track....For us mortals as club men "trust me " dont even bother to waste your time too much on this!! That was really where I was coming from in my "long" question Les. It seems to me that for most, ie excepting the top tier, you do not need all the adjustments possible, as some of the differences are going to be very subtle - of course I do not have the 19T or mod experience to back up that statement. Yes you should experiment with everything to try and understand what it does and does not do for you but I expect most of us end up with our favourites - I certainly have with my experience of Xray chassis.
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Post by yellowshark on Oct 2, 2008 18:30:48 GMT
OK I am going to stick my kneck out and offer an alternative view on where to measure droop. Unless you are following someone else's setup sheet it does not matter, as long as YOU always use the same point under the suspension arm. Indeed it is not actually the droop setting you are interested in, it is the uplift measurement - which is the end result of your ride height and downstop settings. Whilst I setup the car using the ride height and droop guages, I always then check to ensure the front and rear uplift measurements are as expected.
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Post by yellowshark on Oct 2, 2008 19:05:14 GMT
We have developed a different strategy this year. No politics here, seriously this is a result of the 008 chassis.
No matter where we have been, the 008 with its Bashley setup has performed nicely on its first outing on the strange track. The point being that the setup is on the ball and any tuning is therefore very incremental. The 007 was not like this at all! The difference is like laying down beside Enid Sharples and then changing to Danni Minougue ;D
So Craig runs two or three packs to get the hang of the new track and then we take his feedback (which is either "great" or "a bit loose" "err which end Craig?"), my visual asssessment and a view of the track overall in terms of what theorically would make sense - irrespective of whether the care is deemed "great" or not. .
So eg at Cotwolds. The car was nicely balanced from the start with the Bashley setup. But given the style of track and the good level of grip that was being given up, it made sense to me to go down the route of stiffening the car up. So we stiffened up the the chassis and top deck, nice result, no loss of grip and and even I could see on the first lap that high speed turn in was better. We changed to harder springs. I couldn't be naffed with changing the oil as we were after all going to get stuffed by the 13.5s no matter what we did, but I closed up the holes on the adjustable shocks. More improvement. And there we stopped because Craig's view was "great"and it looked great to me too.
Now no doubt we could have continued; play around with ride height, play around with droop. But our strategy now is to spend as much time as possible learning the track with an unchanged car. Our view being that if you get the car in good shape you will gain more by spending hours circumnavigating the track, getting the lines right and getting your rythmn; rather than continually changing the handling, for better or for worse.
Now I am not suggesting that approach works for all. The top guys like Les and Ed will no doubt recognise a twitch, come off make a change, if that doesn't work make another change and then that one twitch on that one corner disappears.
But is does seem to me that for the less experienced, worrying less about setup - getting rid of that one twitch on that one corner - and more about how you drive that track will be more beneficial. I know I don't drive but Craig and I have discussed this a lot this year and that is his view too.
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Post by Simon Crabb on Oct 2, 2008 19:43:12 GMT
Nice post Pete, and interesting insight how you and Craig work.
And thanks all re droop measurement, I'm confident what I'm doing is the right sort of thing with that regard!
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Post by issac on Oct 2, 2008 20:24:39 GMT
hows this to confuse things
between the second and third runs the only change was to give more front droop and i took 7 seconds off my time but the car felt slower to drive.
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Post by lesbaldry on Oct 3, 2008 7:20:28 GMT
Cotswolds..Strangley enough my set up ended softer and slightly higher in ride hight than a Bashley set up..confused? so was I !!..more grip,very fast, very flowing..Yes?..stiff car, low ride hight,little droop?..thats what I thought too ,how little I know!!,so I just lowered my Bashley set up a little,reduced droop(lower number=more droop) front and rear and up,ed the spring rate! the car worked and was balanced but I could,nt carry corner speed,Brake hard safely or change direction quickly for the S'es befor the rostrom...all the things required for a fast lap there!!....Basicaly the car needed to roll to allow side bite to carry corner speed and pitch front to rear to allow fierce braking and turn in. Cure "for me"...more droop on front from 5 to 4mm with six mm ride hight =10 mm uplift, room to pitch for hard braking with the same measurements on the rear but a slightly softer spring on the front(from gold to pinks) after this the car was dramatically improved..But it would not rotate well in fast corners,ie oversteer half way round a fast bend and would have to be corrected with steering and throttle making it difficult to drive,slower!!.. a simple cure was found and I MEAN simple,basically the wheel base and rear drive point was lengthened by 2mm by shifting a 2mm shim from the back of the rear hub forward..my gain was well over half a second a lap the car was a peach to drive giving me confidence to push hard..my point been is that a small change can really improve your times!! How did I find that small 2mm change? I didn't, someone else did for me.I would have never thought of it,I would have gone down the route of changing roll centers or roll bars to cure the prob or even,Oh dear "shock,horror "Akerman ;D ;D...Another known Cyclone driver in stock was suffering with a small problem so we swapped info(purple camaraderie )..My luck more than judgment
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Post by yellowshark on Oct 3, 2008 12:37:37 GMT
Ah that was the advantage of running 27T Les, we didn't have any speed to worry about carrying through the corner ;D
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Post by yellowshark on Oct 3, 2008 13:02:26 GMT
hows this to confuse things between the second and third runs the only change was to give more front droop and i took 7 seconds off my time but the car felt slower to drive. I assume Ian that that this gave you more rear end grip on corner exit and maybe you were sliding a bit as you rotated the corner (ooh this is is on the edge, going real fast) and after the change the car just went around with any antics. This is an interesting one becuase I think style comes into it. Some people like corner exit oversteer. Indeed we ran the 007 like that last year, not because we wanted to but because I couldn't tame the rear end and anyway Craig liked it. But as I said to him, look whilst you are sliding on exit you ain't going forward - I could see people pulling 4 or 5 feet on him between the top left hand corner and the tyre. I don't know whether Derek would agree but I think this is one where the father/son combination has the advantage. Yes it is sometimes difficult to interpret what is happening on the track because you cannot tell what inputs the driver is giving at any moment in time so you are dependent on feedback, and getting a helpful interpretation is not always easy! But you can see the cars handling at any point in relation to other cars. I certainly see things that Craig doesn't and have made changes, that he has not always agreed are necessary, and got it right.
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Post by lesbaldry on Oct 3, 2008 13:28:07 GMT
hows this to confuse things between the second and third runs the only change was to give more front droop and i took 7 seconds off my time but the car felt slower to drive. I assume Ian that that this gave you more rear end grip on corner exit and maybe you were sliding a bit as you rotated the corner I don't know whether Derek would agree but I think this is one where the father/son combination has the advantage. Yes it is sometimes difficult to interpret what is happening on the track because you cannot tell what inputs the driver is giving at any moment in time so you are dependent on feedback, and getting a helpful interpretation is not always easy! But you can see the cars handling at any point in relation to other cars. I certainly see things that Craig doesn't and have made changes, that he has not always agreed are necessary, and got it right. I think you will find Ian went down the same road as me with droop Pete (see previous post)...his lower roll centers were not the "norm" either!!
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Post by lesbaldry on Oct 3, 2008 13:29:52 GMT
Ah that was the advantage of running 27T Les, we didn't have any speed to worry about carrying through the corner ;D with time you could have got a lot more from that car ..I set up my 008 sat morning as a spare should I need it...It was a long way from kit spec, opposite to way that you went...I very nearly used it as my race car..d/shaft probs ..besides I was trying to give as much set up help to my fellow purple pilots ;D ;D ;D Hopefully you will be putting that 13.5 to good use soon? the extra power/torque will show up any flaws in your build/set up. I hope its a pleasant new learning period for you and Craig ...good luck with brushless
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Post by Martin Young on Oct 14, 2008 7:08:37 GMT
Hi Guy’s After unfortunately another struggle at the weekend with Lucas’ car all tweaks and changes tried so far have failed to deliver any rear end grip. Not only the lack of grip but Lucas is now getting into bad driving habits trying to drive a car that just does not handle. All day he drove the car very aggressively letting off the throttle entering the corner, the car rear would then start to slide and he would then nail the throttle and try and control it on the slide. I like many others told him to be more gentle with the car and accelerate smoothly. Then I drove the car after the last race, it was horrible the only way to keep the rear end from spinning out was as Lucas was doing to hit the throttle in an attempt to control the car , not an easy way to drive for sure. Now comes the question the rear of the car has 3deg of toe in but it has 1deg inboard and 2deg at the hubs, what affect would this have? I guess less rear end grip than 3 deg inboard toe. If someone could explain more regarding rear toe in it would be greatly appreciated. I have to say a big thank you to the Staples family for the help and assistance during the day it was very much appreciated.
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Post by lesbaldry on Oct 14, 2008 8:18:00 GMT
Martin the Estate body shell is not helping maters,I ran a Audi 80 shell as a tow car in a caravan race a few years ago and as for a race shell forget it! it was like running a car without any shell fitted,absolutely no rear down force!! my advice to you would be to dump that shell ASAP fit a proper TC shell and go from there.It has the aerodynamics of a shoe box As for off set rear hub/lower arm sweep suspension and its effects,this sort of adjustment is normally done with "hop up" option parts on later chassis,s and is not normally played with "never had the need to??" I understand this sort of adjustment/set up effects the rotation and drive/traction out of a corner on power and I doubt will be the cause of your hooking off power problem..sorry chap not sure?..some of the Tamiya lads may have played with it and may help here?
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Post by Martin Young on Oct 14, 2008 16:45:41 GMT
Point taken about the shell, it definately does not help. I will get Lucas to try a proper shell next time we race!!
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Post by number1dan on Oct 14, 2008 18:23:02 GMT
in my experience the best shell at our track is the mazda speed 6
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