the passenger side i tend to set 5-10mm lower (on the adjusters) to counter act the weight of the driver
with 80-100kg on the drivers side it'll sit level
corner weighting is surprising when you measure/adjust it
Also remember the engine is approx 100kg and the box is only 35kg, so there is more weight on the drivers side
Which is why there was never a RHD Cup Racer ;-) On the X85's I can get the fronts within a few KG's of each other - on a RHD 197 I can't get anywhere near that LOL
Craig, when you set your ride heights you really need to do it with either the driver or an equivalent mass in the drivers seat.
Cheers
M
the rears are "normally" within 5kg of each other on the scales with the rear at an identical height
it can get a bit too OTT on setting up cars, (ie depends how many right handers the track has, how many left handers etc etc)
but generally for a track car with the driver sat in, i aim to have the front axle within 10-15kg side to side
rears as said are generaly spot on
LOL and there was me trying to keep things simple and not get too techy and boring!!!
that last sentence is playing havoc with my brain there, do you mean :
".......of equalised distribution on just the fronts for braking balance?"
thats the general idea with most stuff (sorry i was trying to keep things simple as to not to overcomplicate things for people)
but if you're on about race stuff, then you have a lot of experimenting (aka testing!) to do!
the majority of circuits are clockwise so therefore you can set the car to be quicker through the right handers but at the risk of them being dogs through left handers, every track will have a different setting
Appreciate your time and replies Fred.
Ignoring the setting up for a specific circuit or direction. Isn't the objective with a good cross weighted track car ie 50% balanced across the diagonals, that it then has similar handling in both left corners and in right corners ie balanced and predictable for track work in either a left or right turn. Surely if you just corner weight to equalise the fronts (left/right only) the car is only balanced under braking and not well balanced in turns?
It must be just as easy to cross weight the diagonals, so why chose balanced fronts only?
yeah sorry the way i said it sounds a bit daft
you set the statics, then by adjusting say the front left and rear right (or front right rear left) you adjust the diags, but its usually only by small amounts that are needed
i made it sound like the front just need to be equal
sorry my mistake!
what's your background anyway, you know your stuff!
i have, but you won't be getting that out of me! LOL (its mainly camber and toe where i "mess" about with, nothing with the corner weighting is anything special)
na in all seriousness alot of it stems down to preference, if a car comes to me for setup i will ask what they like, setup it up as best i can, let them take it away, do some track work etc etc if its no good then they can come back and i'll try something else £FOC
if i set all cars (clios i'm on about here) to the same setup, then i can gaurantee there will be people who don't like it, some of my lot hate how my car feels, i love it, and likewise their cars
Appreciate your time and replies Fred.
Ignoring the setting up for a specific circuit or direction. Isn't the objective with a good cross weighted track car ie 50% balanced across the diagonals, that it then has similar handling in both left corners and in right corners ie balanced and predictable for track work in either a left or right turn. Surely if you just corner weight to equalise the fronts (left/right only) the car is only balanced under braking and not well balanced in turns?
It must be just as easy to cross weight the diagonals, so why chose balanced fronts only?
I tend to optimise the corner weights for the weight distribution I want (which in turn alters the rake/point) with equal front/rear axle weights and then build on this base setup with feedback from the driver/s. You'll never stick a setup on a car and accept that thats it. You need to work very closely with the guys driving the car to find a setup that compliments their style and nature, some may like it loose on initial turn in, in which case you'd run with less rear weight bias to allow a controlable amount of 'slide' into the corner. Some may like the car absolutely planted i.e. in a 24hr endurance car, in which case you would setup to be as quick as possible whilst being as benign as possible in terms of resistance to slide during rapid weight transfer events......
The best starting point for developing a setup IME is always to start with the car as close to equal axle weights as possible with the weight distribution you require with driver, all fluids and half a tank of fuel on board. From this point you can develop a circuit specific setup which may or may not be optimised for corner direction or optimised diagonaly for equal response.
Cheers
M
Good stuff. So are you moving physical mass about to equalise the front and rear axle loads as you suggested for your corner weighting starting point. I can’t see how you would have a perfect 50/50 Front/Rear weight distribution to start with and you can’t shift the overall Front/Rear balance ratios just on platform heights.
Do your drivers prefer a more balanced set-up or favour a circuit direction orientated set-up? Maybe even once they are running dynamically they cant even tell the difference with a few Kg difference anyway if the circuit conditions vary.
Without doubt one of the most interesting threads on here.
Wondering if someone could answer a few simple questions for me since theres a lot of knowledge looking in!
Got H&R's on my car and I'm wanting to set it up for fast road/occasional track use. However I don't know what a happy medium would be with regards to the setup. I've got some lightweight 15's for track use, but turinis for day to day use, how much difference would it make if it was set up with either? I was thinking none as the weight at each corner would be equal regardless of the 15's or 16's?
Previously had the car set-up with -ve 2.5 on the front, can't remember the castor/toe-in settings off the top of my head, but it was very good on a nice dry road, motorways etc not the best but most of my driving is recreational anyways so that doesnt bother me.
Also I like the low look, but willing to sacrifice this a bit for a good set-up.
I'm also interested in how to have the car setup with the interior etc....for track I plan to strip the rear seats, plastics and seatbelts. However day to day I will have it all in....is it worth leaving it all in on track too so it is set up right for both? Or will the difference be massive?
Sorry if that doesnt make much sense, but overall i want it as good a compromise as possible.
BTW matt am i being dumb here, or is "rake" more of a motorcycle term, as its rare i hear people say that
......What I aim for as a starting point are equal front/rear axle weights not equal front/rear weights. Axle weights being equal side to side weights on that axis. You certainly can influence the front/rear weight distribution via spring platforms though, by several tens of kilos if you want to take it to the extreme on a front engined RWD drift car for example.
Cheers
M
Rake, well slightly Americanised and used by the biker boys for other things, but in this context the differential between front and rear ride heights or chassis inclination from the horizontal. What do you chaps like to call it?
Some good feedback on the corner weighting. I would imagine trying to equalise the front and rear axle weight distributions is just too difficult as a starting point due to the physics across the diagonals and the skewed roll dynamics. I still wonder why you use that as a starting point. You might get the fronts about right but the rears will drift out unless you are very lucky with the raw vehicle weight distribution from left to right, or if you are setting up a mid-mounted single seater with good offset centreline weight distributuion.
I always assumed most like to start with the first cut on ride heights and rake and then fine tune the corners afterwards with minimal platform adjustments rather than trying to set axle loads.
Anyway, you never normally end up with equal left and right axle weight distribution in an offset driver FWD motor in either a balanced or circuit direction orientated set-up.
Point - old term!
You can if its LHD with a conventional engine package or RHD and a Honda assuming the car has been built/packaged well. Biggest issue is usualy the rears.
Worth noting that when adjusting the spring platform on one corner the biggest change will be in the diagonal opposite corner, hence working around the car in a figure of eight probably several if not tens of times to balance it correctly. Whilst doing this you will also be aiming for the F/R weight distribution you are after and this is what determins the point on the car (or rake).
Cheers
M
Not many hatchback or saloon racers have that natural balance though. You can move mass and ballast to try to achieve it, often to the detriment in other areas. Like I said earlier you may get the fronts L/R balanced, if that is what you want, but as you said, you won’t achieve the rears..
Yes, I’m happy with all the mass ratio constants front to rear, left to right and the effect on the diagonals. You can’t beat the physics and the adjustments all revolve around the interplay with diagonal mass distributions.
You cannot really change or aim for a F/R weight distribution by corner weighting though can you? I’m a bit confused by that. You only alter the L/R distributions on the front or rear axles and not the total amounts on each axle.
.
Corner weight scales can offer a lot more than just corner weights ;-)
Cheers
M
If you raise total rear ride height and/or reduce total front ride height (or vice versa) you will effect the total amount of mass on each axle. My scales even have a button on them to aid with weight distribution setup.... and one to calculate COG. The trick is maintaining the ideal % of F/R weight distribution whilst also achieving as ideal as possible corner weights.
Corner weight scales can offer a lot more than just corner weights ;-)
Cheers
M
Interesting concept - Raising and lowering total front or rear ride heights just to adjust weight distribution. You would have some interesting looking vehicles on the road.