F:R weight bias and corner weights

[sambb]

Hi,

I've done a bit of searching re front :rear weight distribution of our car. Eddy once commented that his car was 800kg front:400kg rear, Sean once said his was 65:35% and Gav had commented once that the car was light on the left front even with the battery still in its stock location. Problem is I have no idea if these cars have eg different gearboxes, batteries in the boot or if they were weighed with rear seats out and driver weight in the seat.

Just wondering if anyone can post up their weights. If anyone has corner weights of a car with the rear seats out, standard battery location and driver weight in the seat (although a long shot) that would be freakin awesome.

sam

[h100vw]

Mine was light with a small.battery. the car was weighed without seats and spare wheel on that occasion, around half a tank of fuel on board.

[sambb]

Ok that's good to know. Yeah forgot to mention I'd be running without spare and usually on 1/4 tank too so probably 65kg lighter in the rear I suppose. Can you remember if the split across the rears was more or less equal?

[h100vw]

Ok that's good to know. Yeah forgot to mention I'd be running without spare and usually on 1/4 tank too so probably 65kg lighter in the rear I suppose. Can you remember if the split across the rears was more or less equal?

Pretty sure there's a photo of the scales in my thread Sam. Be about 18 months ago.

[sambb]

I found the numbers. Can you remember if thats the before or after numbers? Did they play with preloads or corner weights to adjust for that front cross discrepancy?

[h100vw]

I found the numbers. Can you remember if thats the before or after numbers? Did they play with preloads or corner weights to adjust for that front cross discrepancy?

Pretty sure that was how it looked before we started the install.

Gavin

[seangti]

Whilst I can't recall the actual weight, my silver polo was 60/40 F:R when corner weighed. That's on spring/strut suspension with no adjustment (as it's not possible). That's with seats, 3/4 tank of fuel, probably without spare tyre but can't recall. The red polo was 65/35 and obviously lighter and I think with very little fuel. I don't get held up on fuel. Fuel is light with a specific weight of 0.72:1, i.e. 0.72kg per litre.

Bank on stock polo being near enough 60:40 with seats.

[sambb]

I run mine with no spare (-20kg), no rear seats (-20kg+) and 1/3 tank max (-20kg) and front seat pushed forward and folded flat. I only weigh 70kg. I've found a bit of an issue where the whiteline front bar is actually bent. The adjustment blade is actually twisted and with the passenger side droplink in, the drivers side is really hard to get in. So I'll have to make an adjustable link to correct the FARB preload and then I wouldn't mind getting it weighed with me in it (and in event trim) to see whats what. Basically if its close I won't go coilovers, if its well out then I might consider them for next year.
Just thinking, with normal struts you could use front bar preload to correct the left front to right front discrepancy couldn't you? Or at least you could statically/in ride but I'm not sure what would happen during a corner/in roll. any thoughts

[rgvlee]

How did you bend the whiteline FSB?
On track I leave all the running gear in (seats, rear tyre, tool kit etc)
I found the bum end just too loose without it.
Maybe a different story when I do the RSB.

[sambb]

No collision or anything like that from my end. I did swear at it and probably hit it a little trying to get the dam thing fitted but that's about it. Either it was tempered that way or bent in transit but I never noticed until it was already in and the whole front end put back together. Its funny, but looking down the length of the flattened blade adjustment part of the bars arm, it isn't bent left or right but is actually twisted clockwise. I need to force the bar (i think) down like a mofo just to get the bolt through and then crank it up from there. It'd have to be preloading one side a lot - I guess lifting the driver side front a little That's partly why I was asking about the left:right front weight split because the preload that's there now could either be making it worse or perhaps correcting for it??
Yeah the car can be pretty tailey with the guts out of the back and low fuel. I ran one event with street semi's on the front and street tyres on the rear and it was worse than my old escort! I run the whiteline rear bar on full hard so that it will lift the inside rear a little, but have lowered and softer than stock rear springs that counteracts the stiff bar a bit. UI have standard rear toe which makes it a little more stable in the rear than shimmed cars would probably be. Its perfectly civilised with everything in it inc two baby seats on the street but a different car entirely when its on the track with the weight out of the back. I do hillclimbs though and can get away with that kind of setup a bit (so far!). At track speeds I'd have to be really careful. I've just taken the advice of hillclimbers and go for as much front percentage as I can to maximise front end traction on inclines - that's why I gut it.
If you think the car is already tending towards oversteer when gutted, a RSB will only exacerbate that unless you soften the rears you have in there to compensate for the bar, Or stiffen the front at the same time. Its all fun though.

[h100vw]

I mustn't drive hard enough, I never feel the back end letting go.

[rgvlee]

I mustn't drive hard enough, I never feel the back end letting go.

With your reported fuel consumption and tyre longevity, I suspect this is 100% the case

[h100vw]

With your reported fuel consumption and tyre longevity, I suspect this is 100% the case

Steady on Lee, 730km on this tank and it only just went to 0km to empty. I reckon if I was brave, it would do 800.

Calculated off the MFA and injector size, it's under 6.5l/100.

I do hang it hard around the roundabouts and on ramps. Where having the back out would end up in bodywork required.

Gavin

[Martin]

When looking at corner weights it's the sum of the diagonals that really matters
As per the ComputerScales, your diagonal is 50.6% - would not waste any time on it
You have a 15 kg variance, it's normal for production cars to have a 50kg variance

Josh at MCA suspension does not bother corner weighting his time attack car

I found the numbers. Can you remember if thats the before or after numbers? Did they play with preloads or corner weights to adjust for that front cross discrepancy?

[sambb]

Oh yeah I know that 50% is basically perfect isn't it. Still it's be interesting to see what it'd be with driver weight in it. From (poor) memory I thought it had been worse than that and I was worried my bar issue might be taking it even further. Anyone selling whiteline adjustable droplinks??